gsoap xml 自动映射 C/C++
2016-04-22 13:15
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The first simple example
how to use wsdl2h to bind an XML schema to C++. The C++ application reads and writes an XML file into and from a C++ "address book" data structure. The C++ data structure is an STL vector of address objects.
The second example
how XML is serialized as a tree, digraph, and cyclic graph. The digraph and cyclic graph serialization rules are similar to SOAP 1.1/1.2 encoded multi-ref elements with id-ref attributes to link elements through IDREF XML references, creating a an XML graph
with pointers to XML nodes.
These examples demonstrate XML data bindings only for relatively simple data structures and types. The gSOAP tools support more than just these type of structures to serialize in XML. There are practically no limits to enable XML serialization of C and C++
types.
Support for XML schema components is unlimited. The wsdl2h tool maps schemas to C and C++ using built-in intuitive mapping rules, while allowing the mappings to be customized using a
with mapping instructions for wsdl2h.
The information in this document is applicable to gSOAP 2.8.26 and higher, which supports C++11 features. However, C++11 is not required to use this material and the examples included, unless we need smart pointers and scoped enumerations. While most of
the examples in this document are given in C++, the concepts also apply to C with the exception of containers, smart pointers, classes and their methods. None of these exceptions limit the use of the gSOAP tools for C in any way.
The data binding concepts described in this document were first envisioned in 1999 by Prof. Robert van Engelen at the Florida State University. An implementation was created in 2000, named "stub/skeleton compiler". The first articles on its successor version
"gSOAP" appeared in 2002. The principle of mapping XSD components to C/C++ types and vice versa is now widely adopted in systems and programming languages, including Java web services and by C# WCF.
We continue to be committed to our goal to empower C/C++ developers with powerful autocoding tools for XML. Our commitment started in the very early days of SOAP by actively participating in SOAP
interoperability testing, participating in the development and testing of the W3C XML Schema Patterns for Databinding Interoperability,
and continues by contributing to the development of OASIS open standards in partnership with leading IT companies.
This command converts WSDL and XSD files to C++ (or pure C with wsdl2h option
and saves the data binding interface to a gSOAP header file
uses familiar C/C++ syntax extended with
annotations. Notational conventions are used in the data binding interface to declare serializable C/C++ types and functions for Web service operations.
The WSDL 1.1/2.0, SOAP 1.1/1.2, and XSD 1.0/1.1 standards are supported by the gSOAP tools. In addition, the most popular WS specifications are also supported, including WS-Addressing, WS-ReliableMessaging, WS-Discovery, WS-Security, WS-Policy, WS-SecurityPolicy,
and WS-SecureConversation.
This document focusses on XML data bindings. XML data bindings for C/C++ bind XML schema types to C/C++ types. So integers in XML are bound to C integers, strings in XML are bound to C or C++ strings, complex types in XML are bound to C structs or C++ classes,
and so on.
A data binding is dual. Either you start with WSDLs and/or XML schemas that are mapped to equivalent C/C++ types, or you start with C/C++ types that are mapped to XSD types. Either way, the end result is that you can serialize C/C++ types in XML such that
your XML is an instance of XML schema(s) and is validated against these schema(s).
This covers all of the following standard XSD components with their optional attributes and properties:
And also the following standard XSD directives are covered:
The XSD facets and their mappings to C/C++ are:
All primitive XSD types are supported, including but not limited to the following XSD types:
All other primitive XSD types not listed above are mapped to strings, by wsdl2h generating a typedef to string for these types. For example,
bound to a C++ or C string:
typedef std::string xsd__token;
// C++
typedef
char *xsd__token;
// C (wsdl2h option -c)
This associates a compatible value space to the type with the appropriate XSD type name used by the soapcpp2-generated serializers.
It is possible to remap types by adding the appropriate mapping rules to
we will explain in more detail in the next section.
Imported custom serializers are intended to extend the C/C++ type bindings when the default binding to string is not satisfactory to your taste and if the target platform supports these C/C++ types. To add custom serializers to
wsdl2h, see adding custom serializers below.
namespace prefixes and to customize type bindings for the the generated header files produced by the wsdl2h tool. The
the default file processed by wsdl2h. Use wsdl2h option
specify a different file.
Declarations in
broken up over multiple lines by continuing on the next line by ending each line to be continued with a backslash
The limit is 4095 characters per line, whether the line is broken up or not.
etc. as schema-binding URI prefixes. These default prefixes are generated somewhat arbitrarily for each schema targetNamespace URI, meaning that their ordering may change depending on the WSDL and XSD order of processing with wsdl2h.
Therefore, it is strongly recommended to declare your own prefix for each schema URI in
reduce maintaince effort of your code. This is more robust when anticipating possible changes of the schema(s) and/or the binding URI(s) and/or the tooling algorithms.
The first and foremost important thing to do is to define prefix-URI bindings for our C/C++ code by adding the following line(s) to our
make a copy of this file and add the line(s) that bind our choice of prefix name to each URI:
For example:
This produces
names that are bound to the "urn:graph" schema by association of
the generated C/C++ types.
This means that
parsed as an instance of a
type. Also
as an instance of
the prefix
Prefixes in XML have local scopes (like variables in a block).
The first run of wsdl2h will reveal the URIs, so you do not need to search WSDLs and XSD files for all of the target namespaces. Just copy them from the generated header file after the first run into
editing.
associate C/C++ types with specific schema types. These type bindings have four parts:
where
to be customized (the
uses the common double underscore naming convention);
in the wsdl2h-generated header file. This part can be empty if no explicit declaration is needed;
how the C/C++ type is used in the code. When omitted, it is the same as
specifies how the type is used as a pointer type. By default it is the
name with a
enabled (see further below).
For example, to map
a
type that holds millisecond duration values, we can use the custom serializer declared in
adding the following line to
Here, we omitted the second field, because
the name that wsdl2h uses to identify and use this type for our code. The third field is omitted to let wsdl2h use
smart pointers are enabled.
To map
strings:
Note that the first field is empty, because
a C type and does not need to be declared. A
is given so that we do not end up generating the wrong pointer types, such as
When the auto-generated declaration should be preserved but the
replaced, then we use an ellipsis for the declaration part:
This is useful to map schema polymorphic types to C types for example, where we need to be able to both handle a base type and its extensions as per schema extensibility. Say we have a base type called ns:base that is extended, then we can remap this to
a C type that permits referening the extended types via a
follows:
such that
be used to (de)serialize any data type, including base and its derived types. The
is set to a
what type of data the
points to.
a
type to store millisecond duration values:
The
of
While wsdl2h will use this binding declared in
you will also need to compile
Each custom serializer has a header file and an implementation file written in C. You can compile these in C++ (rename files to
needed).
We will discuss the custom serializers that are available to you.
a string by default. To map
the 128 bit big int type
The
of
WarningBeware that the
space of integers is in principle unbounded and values can be of arbitrary length. A value range fault
exceeds native representation) or
exceeds range bounds) will be thrown by the deserializer if the value is out of range.
Other XSD integer types that are restrictions of
are
which are further restricted by
To bind these types to
should also add the following definitions to
NoteIf
bit integers are not supported on your platform and if it is certain that
are within 64 bit value bounds for your application's use, then you can map this type to
Again, a value range fault
be thrown by the deserializer if the value is out of range.
See alsoSection numerical types.
a string by default. To map
extended precision floating point:
By contrast to all other custom serializers, this serializer enables
NOT defined).
If your system supports
precision floating point
you can map
is an alias of
WarningBeware that
in principle a decimal value with arbitraty lengths. A value range fault
be thrown by the deserializer if the value is out of range.
In the XML payload the special values
plus or minus infinity and not-a-number, respectively.
See alsoSection numerical types.
default.
The trouble with
as 32 bit
is limited to dates between 1970 and 2038. A 64 bit
safe to use if the target platform supports it, but lack of 64 bit
may still cause date range issues.
For this reason
be used to represent wider date ranges. This custom serializer avoids using date and time information in
You get the raw date and time information. You only lose the day of the week information. It is always Sunday (
To map
is an alias of
If the limited date range of
not a problem but you want to increase the time precision with fractional seconds, then we suggest to map
If the limited date range of
not a problem but you want to use the C++11 time point type
internally uses
Again, we should make sure that the dates will not exceed the date range when using the default
for
These are safe to use in applications that use
record date stamps within a given window. Otherwise, we recommend the
a plain string (use
C++). For example:
See alsoSection date and time types.
a string by default. We can map
The
See alsoSection date and time types.
a string by default. We can map
an
integer with microsecond time precision:
This type represents 00:00:00.000000 to 23:59:59.999999, from
an upper bound of
resolution means that a 1 second increment requires an increment of 1000000 in the integer value. The serializer adds a UTC time zone.
See alsoSection date and time types.
a string by default, unless
mapped to a
type with with millisecond (ms) time duration precision:
The
signed integer that can represent 106,751,991,167 days forwards (positive) and backwards (negative) in time in increments of 1 ms (1/1000 of a second).
Rescaling of the duration value by may be needed when adding the duration value to a
because
a seconds resolution, depending on the platform and possible changes to
Rescaling is done automatically when you add a C++11
to a
To use
This type can represent 384,307,168 days (2^63 nanoseconds) forwards and backwards in time in increments of 1 ns (1/1,000,000,000 of a second).
Certain observations with respect to receiving durations in years and months apply to both of these serializer decoders for
See alsoSection time duration types.
For example, we can add method declarations and private members to a class, say
follows:
Note that method declarations cannot include any code, because soapcpp2's input permits only type declarations, not code.
This replaces all
the wsdl2h output.
WarningDo not agressively replace types, because this can cause XML validation to fail when a value-type mismatch is encountered in the XML input. Therefore, only replace similar types with other similar types that are wider (e.g.
defines the container to emit in the generated declarations, which is
default. For example, to emit
the container in the wsdl2h-generated declarations:
The
defines the smart pointer to emit in the generated declarations, which replaces the use of
For example:
Not all pointers in the generated output can be replaced by smart pointers. Regular pointers are still used as union members and for pointers to arrays of objects.
NoteThe standard smart pointer
generally safe to use. Other smart pointers such as
cause compile-time errors when classes have smart pointer members but no copy constructor (a default copy constructor). A copy constructor is required for non-shared smart pointer copying or swapping.
Alternatives to
the form
be assigned to
implements
when the shared pointer class provides
and the dereference operator. For example Boost
The user-defined content between
that we include the Boost header files that are needed to support
enclosing it within brackets
in the
two brackets MUST appear at the start of a new line.
For example, we can add an
the wsdl2h-generated output as follows:
which emits the
at the start of the wsdl2h-generated header file.
where
that declares the XML data binding interface. The
typically generated by wsdl2h, but you can also declare one yourself. If so, add
declare in this file all our C/C++ types you want to serialize in XML.
You can also declare functions that will be converted to Web service operations by soapcpp2. Global function declarations define service operations, which are of the form:
int prefix__func(arg1, arg2, ..., argn, result);
where
...,
of the input and
argument for the output, which must be a pointer or reference to the result object to be populated. More information can be found in the gSOAP
user guide.
See alsoSection C++ bool and C alternative.
See alsoSection enumerations and bitmasks.
See alsoSection numerical types.
See alsoSection string types.
See alsoSection date and time types.
See alsoSection time duration types.
See alsoSection classes and structs.
See alsoSection special classes and structs.
and XSD files are converted to C/C++. Also, C++ namespaces are not sufficiently rich to capture XML schema namespaces accurately, for example when class members are associated with schema elements defined in another XML namespace and thus the XML namespace
scope of the member's name is relevant, not just its type.
However, from a C/C++ centric point of view this can be cumbersome. Therefore, colon notation is an alternative to physically augmenting C/C++ names with prefixes.
For example, the following class uses colon notation to bind the
to the
//gsoap ns schema namespace: urn:types
class
ns:record // binding 'ns:' to a type name
{
public:
std::string name;
uint64_t SSN;
ns:record *spouse;
// using 'ns:' with the type name
ns:record();
// using 'ns:' here too
~ns:record();
// and here
};
The colon notation is stripped away by soapcpp2 when generating the data binding implementation code for our project. So the final code just uses
identify this class and its constructor/destructor.
When using colon notation make sure to be consistent and not use colon notation mixed with prefixed forms. The name
from
compiled to an unqualified
Colon notation also facilitates overruling the elementFormDefault and attributeFormDefault declaration that is applied to local elements and attributes, when declared as members of classes, structs, and unions. For more details, see qualified
and unqualified members.
A C/C++ identifier name (a type name, member name, function name, or parameter name) is translated to an XML tag name by the following rules:
Two leading underscores indicates that the identifier name has no XML tag name, i.e. this name is not visible in XML and is not translated.
A leading underscore is removed, but the underscore indicates that: a) a struct/class member name or parameter name has a wildcard XML tag name (i.e. matches any XML tag), or b) a type name that has a document
root element definition.
Trailing underscores are removed (i.e. trailing underscores can be used to avoid name clashes with keywords).
Underscores within names are translated to hyphens (hyphens are more common in XML tags).
in the translated XML tag name.
in the translated XML tag name.
character with code point HHHH.
C++11 Unicode identifier name characters in UTF-8 are translated as-is.
For example, the C/C++ namespace qualified identifier name
translated to the XML tag name
translating the prefix
local name
Struct/class member and parameter name translation can be overruled by using backtick XML tags (with gSOAP 2.8.30
or higher).
XSD type
The C alternative is to define an enumeration:
enum xsd__boolean { false_, true_ };
or by defining an enumeration in C with pseudo-scoped enumeration constants:
enum xsd__boolean { xsd__boolean__false, xsd__boolean__true };
The XML value space of these types is
but also accepted are
for false and true, respectively.
To prevent name clashes,
an underscore. Trailing underscores are removed from the XML value space.
and
Consider for example:
enum ns__Color { RED, WHITE, BLUE };
which maps to a simpleType restriction of
the soapcpp2-generated schema:
Enumeration name constants can be pseudo-scoped to prevent name clashes, because enumeration name constants have a global scope in C and C++:
enum ns__Color { ns__Color__RED, ns__Color__WHITE, ns__Color__BLUE };
You can also use C++11 scoped enumerations to prevent name clashes:
enum class ns__Color : int { RED, WHITE, BLUE };
Here, the enumeration class base type
the example above, we can also use
or
The XML value space of the enumertions defined above is
and
Prefix-qualified enumeration name constants are mapped to simpleType restrictions of
for example:
enum ns__types { xsd__int, xsd__float };
which maps to a simpleType restriction of
the soapcpp2-generated schema:
Enumeration name constants can be pseudo-numeric as follows:
enum ns__Primes { _3 = 3, _5 = 5, _7 = 7, _11 = 11 };
which maps to a simpleType restriction of
The XML value space of this type is
and
Besides (pseudo-) scoped enumerations, another way to prevent name clashes accross enumerations is to start an enumeration name constant with one underscore or followed it by any number of underscores, which makes it unique. The leading and trailing underscores
are removed from the XML value space.
enum ns__ABC { A, B, C };
enum ns__BA { B, A };
// BAD: B = 1 but B is already defined as 2
enum ns__BA_ { B_, A_ };
// OK
The gSOAP soapcpp2 tool permits reusing enumeration name constants across (non-scoped) enumerations as long as these values are assigned the same constant. Therefore, the following is permitted:
enum ns__Primes { _3 = 3, _5 = 5, _7 = 7, _11 = 11 };
enum ns__Throws { _1 = 1, _2 = 2, _3 = 3, _4 = 4, _5 = 5, _6 = 6 };
A bitmask type is an
enumeration with a geometric, power-of-two sequence of values assigned to the enumeration constants:
enum* ns__Options { SSL3, TLS10, TLS11, TLS12 };
where the product enum assigns 1 to
2 to
and 8 to
enumeration constants to be used in composing bitmasks with
or)
not):
enum ns__Options options = (enum ns__Options)(SSL3 | TLS10 | TLS11 | TLS12);
if (options & SSL3)
// if SSL3 is an option, warn and remove from options
{
warning();
options &= ~SSL3;
}
The bitmask type maps to a simpleType list restriction of
the soapcpp2-generated schema:
The XML value space of this type consists of all 16 possible subsets of the four values, represented by an XML string with space-separated values. For example, the bitmask
You can also use C++11 scoped enumerations with bitmasks:
enum*
class ns__Options { SSL3, TLS10, TLS11, TLS12 };
The base type of a scoped enumeration bitmask, when explicitly given, is ignored. The base type is either
depending on the number of constants enumerated in the bitmask.
To convert
bitmasks to a string, we use the auto-generated function for enum
const
char *soap_T2s(struct soap*,
enum T val)
The string returned is stored in an internal buffer of the current
so you MUST copy it to keep it from being overwritten. For example, use
To convert a string to an
or bitmask, we use the auto-generated function
int soap_s2T(struct soap*,
const
char *str, enum T *val)
This function takes the name (or names, space-separated for bitmasks) of the enumeration constant in a string
Names should be given without the pseudo-scope prefix and without trailing underscores. The function sets
the corresponding integer enum constant or to a bitmask. The function returns
on success or an error if the string is not a valid enumeration name.
The
serializable) because its width is platform dependent. We recommend to use
The XML value space of integer types are their decimal representations without loss of precision.
The XML value space of floating point types are their decimal representations. The decimal representations are formatted with the printf format string "%.9G" for floats and the printf format string "%.17lG" for double. To change the format strings, we can
assign new strings to the following
soap.float_format =
"%g";
soap.double_format =
"%lg";
soap.long_double_format =
"%Lg";
Note that decimal representations may result in a loss of precision of the least significant decimal. Therefore, the format strings that are used by default are sufficiently precise to avoid loss, but this may result in long decimal fractions in the XML
value space.
The
point type requires a custom serializer:
#import "custom/long_double.h"
... use
long double ...
You can now use
has a serializer that serializes this type as
Compile and link your code with
The value space of floating point values includes the special values
and
plus or minus infinity and not-a-number as follows:
soap_isinf(x) && x > 0
// is x INF?
soap_isinf(x) && x < 0
// is x -INF?
soap_isnan(x)
// is x NaN?
To assign these values, use:
// x is float // x is double, long double, or __float128
x = FLT_PINFY; x = DBL_PINFTY;
x = FLT_NINFY; x = DBL_NINFTY;
x = FLT_NAN; x = DBL_NAN;
If your system supports
you can also use this 128 bit floating point type with a custom serializer:
#import "custom/float128.h"
... use xsd__decimal ...
Then use the
which has a serializer. Do not use
which is transient (not serializable).
To check for
and
use:
isinfq(x) && x > 0
// is x INF?
isinfq(x) && x < 0
// is x -INF?
isnanq(x)
// is x NaN?
The range of a typedef-defined numerical type can be restricted using the range
with inclusive lower and upper bounds. For example:
typedef
int ns__narrow -10 : 10;
This maps to a simpleType restriction of
the soapcpp2-generated schema:
The lower and upper bound of a range are optional. When omitted, values are not bound from below or from above, respectively.
The range of a floating point typedef-defined type can be restricted within floating point constant bounds.
Also with a floating point typedef a printf format pattern can be given of the form
format decimal values using the given width and precision fields:
typedef
float ns__PH
"%5.2f" 0.0 : 14.0;
This maps to a simpleType restriction of
the soapcpp2-generated schema:
For exclusive bounds, we use the
instead of the
typedef
float ns__epsilon 0.0 < 1.0;
Values
restricted between
This maps to a simpleType restriction of
the soapcpp2-generated schema:
To make just one of the bounds exclusive, while keeping the other bound inclusive, we add a
the left or on the right side of the range ':' operator. For example:
typedef
float ns__pos 0.0 < : ;
// 0.0 < pos
typedef
float ns__neg : < 0.0 ;
// neg < 0.0
It is valid to make both left and right side exclusive with
typedef
float ns__epsilon 0.0 < : < 1.0;
// 0.0 < eps < 1.0
It helps to think of the
of the value between the two bounds, which is easier to memorize than the shorthand forms of bounds from which the
removed:
Besides
#import "custom/long_double.h"
typedef
long double ns__probability
"%16Lg" 0.0 < : 1.0;
Value range restrictions are validated by the parser for all inbound XML data. A type fault
be thrown by the deserializer if the value is out of range.
Finally, if your system supports
you can also use this 128 bit integer type with a custom serializer:
#import "custom/int128.h"
... use xsd__integer ...
Use the
which has a serializer. Do not use
which is transient (not serializable).
To convert numeric values to a string, we use the auto-generated function for numeric type
const
char *soap_T2s(struct soap*, T val)
For numeric types
is stored in an internal buffer of the current
so you MUST copy it to keep it from being overwritten. For example, use
To convert a string to a numeric value, we use the auto-generated function
int soap_s2T(struct soap*,
const
char *str, T *val)
where
custom serializer name of
or
name of
success or an error when the value is not numeric. For floating point types, "INF", "-INF" and "NaN" are valid strings to convert to numbers.
types.
The wide strings
contain Unicode that is preserved in the XML value space.
Strings
only contain extended Latin, but we can store UTF-8 content that is preserved in the XML value space when the
WarningBeware that many XML 1.0 parsers reject all control characters (those between
except for
and
parsers (including gSOAP) you should be fine.
The length of a string of a typedef-defined string type can be restricted:
typedef std::string ns__password 6 : 16;
which maps to a simpleType restriction of
the soapcpp2-generated schema:
String length restrictions are validated by the parser for inbound XML data. A value length fault
be thrown by the deserializer if the string is too long or too short.
In addition, an XSD regex pattern restriction can be associated with a string typedef:
typedef std::string ns__password
"([a-zA-Z]|[0-9]|-)+" 6 : 16;
which maps to a simpleType restriction of
the soapcpp2-generated schema:
Pattern restrictions are validated by the parser for inbound XML data only if the
are defined, see the gSOAP user guide.
Exclusive length bounds can be used with strings:
typedef std::string ns__string255 : < 256;
// same as 0 : 255
Fixed-size strings (
rare occurrences in the wild, but apparently still used in some projects to store strings. To facilitate fixed-size string serialization, use soapcpp2 option
For example:
typedef
char ns__buffer[10];
// requires soapcpp2 option -b
which maps to a simpleType restriction of
the soapcpp2-generated schema:
Note that fixed-size strings MUST contain NUL-terminated text and SHOULD NOT contain raw binary data. Also, the length limitation is more restrictive for UTF-8 content (enabled with the
that requires multibyte character encodings. As a consequence, UTF-8 content may be truncated to fit.
Note that raw binary data can be stored in a
or transmitted as a MIME attachment.
The built-in
C string type (
has the added advantage that it holds normalized qualified names. There are actually two forms of normalized QName content, to ensure any QName is represented accurately and uniquely:
"prefix:name"
"\"URI\":name"
The first form of string is used when the prefix (and the binding URI) is defined in the namespace table and is bound to a URI (see the .nsmap file). The second form is used when the URI is not defined in the namespace table and therefore no prefix is available
to bind and normalize the URI to.
A
of space-separated QName values, not just one, and all QName values are normalized to the format shown above.
To define a
for
typedef std::string xsd__QName;
The
normalized, just as with the
To serialize strings that contain literal XML content to be reproduced in the XML value space, use the built-in
type, which is a regular C string type (
that maps to plain XML CDATA.
To define a
for literal XML content, use a typedef:
typedef std::string XML;
Strings can hold any of the values of the XSD built-in primitive types. We can use a string typedef to declare the use of the string type as a XSD built-in type:
typedef std::string xsd__token;
You MUST ensure that the string values we populate in this type conform to the XML standard, which in case of
the lexical and value spaces of
the sets of all strings after whitespace replacement of any occurrence of
and
collapsing.
To copy
with a context that manages the allocated memory, use functions
char *soap_strdup(struct soap*,
const char*)
wchar_t *soap_wstrdup(struct soap*, const
wchar_t*)
To convert a wide string to a UTF-8 encoded string, use function
const char* SOAP_FMAC2 soap_wchar2s(struct soap*,
const
wchar_t *s)
The function allocates and returns a string, with its memory being managed by the context.
To convert a UTF-8 encoded string to a wide string, use function
int soap_s2wchar(struct soap*,
const
char *from, wchar_t **to,
long minlen,
long maxlen)
where
Pass
ignore length constraints on the target string. The function returns
an error when the length constraints are not met.
the built-in
that represents a date and time within a time zone (typically UTC).
The XML value space contains ISO 8601 Gregorian time instances of the form
where
zone offset
used.
A
represented in UTC by the serializer.
Because the
restricted to dates after 01/01/1970 and before 2038 assuming
a
ensure the range of
in XML exchanges do not exceed the
This restriction does not hold for
use to store and exchange a date and time in UTC without date range restrictions. The serializer uses the
struct tm
{
int tm_sec;
// seconds (0 - 60)
int tm_min;
// minutes (0 - 59)
int tm_hour;
// hours (0 - 23)
int tm_mday;
// day of month (1 - 31)
int tm_mon;
// month of year (0 - 11)
int tm_year;
// year - 1900
int tm_wday;
// day of week (Sunday = 0) (NOT USED)
int tm_yday;
// day of year (0 - 365) (NOT USED)
int tm_isdst;
// is summer time in effect?
char* tm_zone;
// abbreviation of timezone (NOT USED)
};
You will lose the day of the week information. It is always Sunday (
and the day of the year is not set either. The time zone is UTC.
This
the built-in
and serialized with the custom serializer
declares a
#import "custom/struct_tm.h"
// import typedef struct tm xsd__dateTime;
... use xsd__dateTime ...
Compile and link your code with
The
type is mapped to the built-in
type and serialized with the custom serializer
declares a
#import "custom/struct_timeval.h"
// import typedef struct timeval xsd__dateTime;
... use xsd__dateTime ...
Compile and link your code with
Note that the same value range restrictions apply to
The added benefit of
the addition of a microsecond-precise clock:
struct timeval
{
time_t tv_sec;
// seconds since Jan. 1, 1970
suseconds_t tv_usec;
// and microseconds
};
A C++11
is mapped to the built-in
type and serialized with the custom serializer
declares a
#import "custom/chrono_time_point.h"
// import typedef std::chrono::system_clock::time_point xsd__dateTime;
... use xsd__dateTime ...
Compile and link your code with
The
built-in
with the custom serializer
declares a
#import "custom/struct_tm_date.h"
// import typedef struct tm xsd__date;
... use xsd__date ...
Compile and link your code with
The XML value space of
Gregorian calendar dates of the form
a time zone.
The serializer ignores the time part and the deserializer only populates the date part of the struct, setting the time to 00:00:00. There is no unreasonable limit on the date range because the year field is stored as an integer (
An
type that contains a 24 hour time in microseconds UTC is mapped to the built-in
type and serialized with the custom serializer
declares a
#import "custom/long_time.h"
// import typedef unsigned long long xsd__time;
... use xsd__time ...
Compile and link your code with
This type represents
from 0 to an upper bound of 86,399,999,999. A microsecond resolution means that a 1 second increment requires an increment of 1,000,000 in the integer value.
The XML value space of
points in time recurring each day of the form
where
zone offset from UTC is used. The
is always considered and represented in UTC by the serializer.
To convert date and/or time values to a string, we use the auto-generated function for type
const
char *soap_T2s(struct soap*, T val)
For date and time types
returned is stored in an internal buffer of the current
so you MUST copy it to keep it from being overwritten. For example, use
To convert a string to a date/time value, we use the auto-generated function
int soap_s2T(struct soap*,
const
char *str, T *val)
where
The function
success or an error when the value is not a date/time.
values of the form
the capital letters are delimiters. Delimiters may be omitted when the corresponding member is not used.
A
type that contains a duration (time lapse) in milliseconds is mapped to the built-in
type and serialized with the custom serializer
declares a
#import "custom/duration.h"
// import typedef long long xsd__duration;
... use xsd__duration ...
Compile and link your code with
The duration type
represent 106,751,991,167 days forward and backward with millisecond precision.
Durations that exceed a month are always output in days, rather than months to avoid days-per-month conversion inacurracies.
Durations that are received in years and months instead of total number of days from a reference point are not well defined, since there is no accepted reference time point (it may or may not be the current time). The decoder simple assumes that there are
30 days per month. For example, conversion of "P4M" gives 120 days. Therefore, the durations "P4M" and "P120D" are assumed to be identical, which is not necessarily true depending on the reference point in time.
Rescaling of the duration value by may be needed when adding the duration value to a
because
a seconds resolution, depending on the platform and possible changes to
Rescaling is done automatically when you add a C++11
to a
To use
#import "custom/chrono_duration.h"
// import typedef std::chrono::duration xsd__duration;
... use xsd__duration ...
Compile and link your code with
This type can represent 384,307,168 days (2^63 nanoseconds) forwards and backwards in time in increments of 1 ns (1/1000000000 second).
The same observations with respect to receiving durations in years and months apply to this serializer's decoder.
To convert duration values to a string, we use the auto-generated function
const
char *soap_xsd__duration2s(struct soap*, xsd__duration val)
The string returned is stored in an internal buffer, so you MUST copy it to keep it from being overwritten, Use
To convert a string to a duration value, we use the auto-generated function
int soap_s2xsd__dateTime(struct soap*,
const
char *str, xsd__dateTime *val)
The function returns
or an error when the value is not a duration.
and string length and pattern constraints.
Classes that are declared with the gSOAP tools are limited to single inheritence only. Structs cannot be inherited.
The class and struct name is bound to an XML namespace by means of the prefix naming convention or by using colon
notation:
//gsoap ns schema namespace: urn:types
class
ns__record
{
public:
std::string name;
uint64_t SSN;
ns__record *spouse;
ns__record();
~ns__record();
protected:
struct soap *soap;
};
In the example above, we also added a context pointer to the
The class maps to a complexType in the soapcpp2-generated schema:
Also
are not serializable, with the exception of
and specific class/struct members can also be made transient with the
extern
class std::ostream;
// declare 'std::ostream' transient
class
ns__record
{
public:
extern
int num;
// not serialized
std::ostream out;
// not serialized
static
const
int MAX = 1024; // not serialized
};
By declaring
with
you need it without soapcpp2 complaining that this class is not defined.
the gSOAP tools. This means that they are already declared elsewhere in your project's source code and you do not want soapcpp2 to generate code with a second declaration of these types.
For example,
in
and include a partial list of data members that you want to serialize:
volatile
struct tm
{
int tm_sec;
// seconds (0 - 60)
int tm_min;
// minutes (0 - 59)
int tm_hour;
// hours (0 - 23)
int tm_mday;
// day of month (1 - 31)
int tm_mon;
// month of year (0 - 11)
int tm_year;
// year - 1900
};
You can declare classes and structs
any such types you want to serialize by only providing the public data members you want to serialize.
In addition, colon notation is a simple and effective way to bind an existing class or struct to a schema. For
example, you can change the
as follows without affecting the code that uses
volatile
struct ns:tm { ... }
This struct maps to a complexType in the soapcpp2-generated schema:
the gSOAP tools. This means that their definition can be spread out over the source code. This promotes the concept of a class or struct as a row of named values, also known as a named tuple, that can be extended at compile time in your source
code with additional members. Because these types differ from the traditional object-oriented principles and design concepts of classes and objects, constructors and destructors cannot be defined (also because we cannot guarantee merging these into one such
that all members will be initialized). A default constructor, copy constructor, assignment operation, and destructor will be assigned automatically by soapcpp2.
mutable
struct ns__tuple
{
@std::string id;
};
mutable
struct ns__tuple
{
std::string name;
std::string value;
};
The members are collected into one definition generated by soapcpp2. Members may be repeated from one definition to another, but only if their associated types are identical. So, for example, a third extension with a
with a different type fails:
mutable
struct ns__tuple
{
float value;
// BAD: value is already declared std::string
};
The
be very useful when declaring and collecting SOAP Headers for multiple services, which are collected into one
the soapcpp2 tool.
class
ns__record
{
public:
std::string name =
"Joe";
...
};
Alternatively, use C++11 default initialization syntax:
class
ns__record
{
public:
std::string name {
"Joe" };
...
};
These initializations are made by the default constructor that is added by soapcpp2 to each class and struct (in C++ only). A constructor is only added when a default constructor is not already defined with the class declaration.
You can explicitly (re)initialize an object with these initial values by using the soapcpp2 auto-generated functions:
Initializations can only be provided for members that have primitive types (
numeric and string types).
See alsoSection operations on classes and structs.
class
ns__record
{
public:
@std::string name;
@uint64_t SSN;
ns__record *spouse;
};
This class maps to a complexType in the soapcpp2-generated schema:
An example XML instance of
Attribute data members are restricted to primitive types (
numeric and string types),
and custom serializers, such as
Custom serializers for types that may be used as attributes MUST define
that convert values of type
and back.
Attribute data members can be pointers and smart pointers to these types, which permits attributes to be optional.
The XML tag name of a class/struct member is the name of the member with the usual XML tag translation, see colon
notation.
To override the standard translation of identifier names to XML tag names of attributes and elements, add the XML tag name in backticks (requires gSOAP 2.8.30 or higher):
class
ns__record
{
public:
@std::string name `full-name`;
@uint64_t SSN `tax-id`;
ns__record *spouse `married-to`;
};
This class maps to a complexType in the soapcpp2-generated schema:
An example XML instance of
A backtick XML tag name may contain any non-empty sequence of ASCII and UTF-8 characters except white space and the backtick character. A backtick tag can be combined with member constraints and default member initializers:
declared with the schema of the class, struct, or union type. If the member name has a namespace prefix by colon notation, then the prefix overrules the default (un)qualified form. Therefore, colon
notation is an effective mechanism to control qualification of tag names of individual members of classes, structs, and unions.
The XML schema elementFormDefault and attributeFormDefault declarations control the tag name qualification of local elements and attributes, respectively.
"unqualified" indicates that local elements/attributes are not qualified with the namespace prefix.
"qualified" indicates that local elements/attributes must be qualified with the namespace prefix.
Individual schema declarations of local elements and attributes may overrule this by using the form declaration in a schema and by using colon notation to add namespace prefixes to class, struct, and union members in the header file for soapcpp2.
Consider for example an
in the
elements are qualified and local attributes are unqualified by default:
//gsoap ns schema namespace: urn:types
//gsoap ns schema elementForm: qualified
//gsoap ns schema attributeForm: unqualified
class
ns__record
{
public:
@std::string name;
@uint64_t SSN;
ns__record *spouse;
};
This class maps to a complexType in the soapcpp2-generated schema with targetNamespace "urn:types", elementFormDefault qualified and attributeFormDefault unqualified:
An example XML instance of
Note that the root element ns:record is qualified because it is a root element of the schema with target namespace "urn:types". Its local element ns:spouse is namespace qualified because the elementFormDefault of local elements is qualified. Attributes are
unqualified.
The default namespace (un)qualification of local elements and attributes can be overruled by adding a prefix to the member name by using colon notation:
//gsoap ns schema namespace: urn:types
//gsoap ns schema elementForm: qualified
//gsoap ns schema attributeForm: unqualified
class
ns__record
{
public:
@std::string ns:name;
// 'ns:' qualified
@uint64_t SSN;
ns__record *:spouse;
// ':' unqualified (empty prefix)
};
The colon notation for member
qualification of its attribute tag in XML. The colon notation for member
qualification from its local element tag:
XML instances of
unqualified spouse elements and qualified ns:name attributes:
Note that data members can also be prefixed using the
However, this has a different effect by referring to global (root) elements and attributes, see document root element
definitions.
Backtick tag names can be used in place of the member name annotations and will achieve the same effect as described
when these tag names are (un)qualified (requires gSOAP 2.8.30 or higher).
NoteYou must declare a target namespace with a
in order to generate valid schemas with soapcpp2. See directives for more details.
class
_ns__record
Alternatively, we can use a typedef to define a document root element with a given type:
typedef ns__record _ns__record;
This typedef maps to a global root element that is added to the soapcpp2-generated schema:
An example XML instance of
Global-level element/attribute definitions are also referenced and/or added to the generated schema when serializable data members reference these by their qualified name:
typedef std::string _ns__name 1 : 100;
class
_ns__record
{
public:
@_QName xsi__type;
// built-in XSD attribute xsi:type
_ns__name ns__name;
// ref to global ns:name element
uint64_t SSN;
_ns__record *spouse;
};
These types map to the following comonents in the soapcpp2-generated schema:
Use only use qualified member names when their types match the global-level element types that they refer to. For example:
typedef std::string _ns__name;
// global element ns:name of type xsd:string
class
_ns__record
{
public: int ns__name;
// BAD: global element ns:name is NOT type int
_ns__record ns__record;
// OK: ns:record is a global-level root element
...
};
Therefore, we recommend to use qualified member names only when necessary to refer to standard XSD elements and attributes, such as
and
By contrast, colon notation has the desired effect to (un)qualify local tag names by overruling the default element/attribute namespace qualification, see qualified
and unqualified members.
As an alternative to prefixing member names, use the backtick tag (gSOAP 2.8.30 and higher):
typedef std::string _ns__name 1 : 100;
class
_ns__record
{
public:
@_QName t `xsi:type`;
// built-in XSD attribute xsi:type
_ns__name s `ns:name`;
// ref to global ns:name element
uint64_t SSN;
_ns__record *spouse;
};
members and their occurrence constraints.
Pointers that are NULL and smart pointers that are empty are serialized to produce omitted element and attribute values, unless an element is required and is nillable.
To control the occurrence requirements of pointer-based data members, occurrence constraints are associated with data members in the form of a range
is prohibited.
is optional.
is required.
Pointer-based data members have a default
constraint, making them optional, and their XML schema local element/attribute definition is marked as nillable. Non-pointer data members have a default
constraint, making them required.
A pointer data member that is explicitly marked as required with
be serialized as an element with an
thus effectively revealing the NULL property of its value.
A non-pointer data member that is explicitly marked as optional with
be set to its default value when no XML value is presented to the deserializer. A default value can be assigned to data members that have primitive types.
Consider for example:
class
ns__record
{
public:
std::shared_ptr<std::string> name;
// optional (0:1)
uint64_t SSN 0:1 = 999;
// forced this to be optional with default 999
ns__record *spouse 1:1;
// forced this to be required (only married people)
};
This class maps to a complexType in the soapcpp2-generated schema:
An example XML instance of
its
to its default, and
NoteIn general, a smart pointer is simply declared as a
in a gSOAP header file for soapcpp2:
volatile
template <class T>
class NAMESPACE::shared_ptr;
NoteThe soapcpp2 tool generates code that uses
create shared pointers to objects, where
any valid C++ namespace such as
you have Boost installed.
serialized as a collection of the values they contain. You can also serialize dynamic arrays, which is the alternative for C to store collections of data. Let's start with STL containers.
You can use
and
#import "import/stl.h"
// import all containers
#import "import/stldeque.h"
// import deque
#import "import/stllist.h"
// import list
#import "import/stlvector.h"
// import vector
#import "import/stlset.h"
// import set
For example, to use a vector data mamber to store names in a record:
#import "import/stlvector.h"
class
ns__record
{
public:
std::vector<std::string> names;
uint64_t SSN;
};
To limit the number of names in the vector within reasonable bounds, occurrence constraints are associated with the container. Occurrence constraints are of the form
#import "import/stlvector.h"
class
ns__record
{
public:
std::vector<std::string> names 1:10;
uint64_t SSN;
};
This class maps to a complexType in the soapcpp2-generated schema:
NoteIn general, a container is simply declared as a template in a gSOAP header file for soapcpp2. All class templates are considered containers (except when declared
see smart pointers). For example,
declared in
template <class T>
class std::vector;
NoteYou can define and use your own containers. The soapcpp2 tool generates code that uses the following members of the
void C::clear()
C::iterator C::begin()
C::const_iterator C::begin() const
C::iterator C::end()
C::const_iterator C::end() const
size_t C::size() const
C::iterator C::insert(C::iterator pos, const T& val)
NoteFor more details see the example
with documentation in the package under
Because C does not support a container template library, we can use a dynamically-sized array of values. This array is declared as a size-pointer pair of members within a struct or class. The array size information is stored in a special size tag member
with the name
where
to identify the member as a special size tag:
struct
ns__record
{
$int sizeofnames;
// array size
char* *names;
// array of char* names
uint64_t SSN;
};
This class maps to a complexType in the soapcpp2-generated schema:
To limit the number of names in the array within reasonable bounds, occurrence constraints are associated with the array size member. Occurrence constraints are of the form
struct
ns__record
{
$int sizeofnames 1:10;
// array size 1..10
char* *names;
// array of one to ten char* names
uint64_t SSN;
};
This class maps to a complexType in the soapcpp2-generated schema:
The variant selector is associated with the union as a selector-union pair of members. The variant selector is a member with the name
where
to identify the member as a variant selector tag:
class
ns__record
{
public:
$int xORnORs;
// variant selector with values SOAP_UNION_fieldname
union
choice
{
float x;
int n;
char *s;
} u;
std::string name;
};
The variant selector values are auto-generated based on the union name
the names of its members
and
valid.
valid.
valid.
(should only be used with great care, because XML content validation may fail when content is required but absent).
This class maps to a complexType with a sequence and choice in the soapcpp2-generated schema:
An STL container or dynamic array of a union requires wrapping the variant selector and union member in a struct:
class
ns__record
{
public:
std::vector<
struct
ns__data // data with a choice of x, n, or s
{
$int xORnORs;
// variant selector with values SOAP_UNION_fieldname
union
choice
{
float x;
int n;
char *s;
} u;
}> data;
// vector with data
};
and an equivalent definition with a dynamic array instead of a
can use this in C with structs):
class
ns__record
{
public:
$int sizeOfdata;
// size of dynamic array
struct
ns__data // data with a choice of x, n, or s
{
$int xORnORs;
// variant selector with values SOAP_UNION_fieldname
union
choice
{
float x;
int n;
char *s;
} u;
} *data;
// points to the data array of length sizeOfdata
};
This maps to two complexTypes in the soapcpp2-generated schema:
The XML value space consists of a sequence of item elements each wrapped in an data element:
To remove the wrapping data element, simply rename the wrapping struct and member to
make this member invisible to the serializer with the double underscore prefix naming convention. Also use a dynamic array instead of a STL container (you can use this in C with structs):
class
ns__record
{
public:
$int sizeOfdata;
// size of dynamic array
struct
__data // contains choice of x, n, or s
{
$int xORnORs;
// variant selector with values SOAP_UNION_fieldname
union
choice
{
float x;
int n;
char *s;
} u;
} *__data;
// points to the data array of length sizeOfdata
};
This maps to a complexType in the soapcpp2-generated schema:
The XML value space consists of a sequence of
and/or
Please note that structs, classes, and unions are unnested by soapcpp2 (as in the C standard of nested structs and unions). Therefore, the
in the
at the top level despite its nesting within the
This means that you will have to choose a unique name for each nested struct, class, and union.
run-time type information that tells the serializer what type of data to serialize by means of a tagged void pointer. This type information is stored in a special type tag member of a struct/class with the name
where
by an
as a type tag:
class
ns__record
{
public:
$int typeOfdata;
// type tag with values SOAP_TYPE_Tvoid *data;
// points to some data of type T};
A type tag member has nonzero values
the name of a struct/class or the name of a primitive type, such as
This class maps to a complexType with a sequence in the soapcpp2-generated schema:
The XML value space consists of the XML value space of the type with the addition of an
to the enveloping element:
This
for the receiving end to distinguish the type of data to instantiate. The receiver cannot deserialize the data without an
You can find the
of each serializable type in the auto-generated soapStub.h file.
Also all serializable C++ classes have a virtual
that you can use.
When the
when
not serialized.
An STL container or dynamic array of
to
the type tag and
struct:
class
ns__record
{
public:
std::vector<
struct
ns__data // data with an xsd:anyType item
{
$int typeOfitem;
// type tag with values SOAP_TYPE_Tvoid *item;
// points to some item of type T}> data;
// vector with data
};
and an equivalent definition with a dynamic array instead of a
can use this in C with structs):
class
ns__record
{
public:
$int sizeOfdata;
// size of dynamic array
struct
ns__data // data with an xsd:anyType item
{
$int typeOfitem;
// type tag with values SOAP_TYPE_Tvoid *item;
// points to some item of type T} *data;
// points to the data array of length sizeOfdata
};
This maps to two complexTypes in the soapcpp2-generated schema:
The XML value space consists of a sequence of item elements each wrapped in a data element:
To remove the wrapping data elements, simply rename the wrapping struct and member to
make this member invisible to the serializer with the double underscore prefix naming convention. Also use a dynamic array instead of a STL container (you can use this in C with structs):
class
ns__record
{
public:
$int sizeOfdata;
// size of dynamic array
struct
__data // contains xsd:anyType item
{
$int typeOfitem;
// type tag with values SOAP_TYPE_Tvoid *item;
// points to some item of type T} *__data;
// points to the data array of length sizeOfdata
};
This maps to a complexType in the soapcpp2-generated schema:
The XML value space consists of a sequence of data elements:
Again, please note that structs, classes, and unions are unnested by soapcpp2 (as in the C standard of nested structs and unions). Therefore, the
in the
at the top level despite its nesting within the
This means that you will have to choose a unique name for each nested struct, class, and union.
See alsoSection XSD type bindings.
to a class or struct, which will be triggered by the deserializer. This method will be invoked right after the instance is populated by the deserializer. The
can be used to update or verify deserialized content. It should return
set
code and return it.
A public
to a class or struct, which will be triggered by the serializer. The method will be invoked just before the instance is serialized. Likewise, the
should return
a nonzero error code and return it.
For example, adding a
to a class declaration:
class
ns__record
{
public: int set(struct soap*);
// triggered before serialization
int
get(struct soap*); // triggered after deserialization
...
};
To add these and othe rmethods to classes and structs with wsdl2h and
please see class/struct member additions.
which should make it easier to send, receive, and copy XML data in C and in C++:
an instance of
descriptor
a stream via
only) or saves into a NUL-terminated string by setting
success or an error code, also stored in
an instance of
descriptor
a stream via
only) or reads from a NUL-termianted string
success or an error code, also stored in
an instance
resetting members of a struct to their initial values (for classes we use method
see below).
deep copy
replicating all deep cycles and shared pointers when a managing soap context is provided as argument. When
NULL, allocates space for
copy is a tree when argument is NULL, but the presence of deep cycles will lead to non-termination. Use flag
managing context to copy into a tree without cycles and pointers to shared objects. Returns
allocated space when
option
members of this object by deep deletion ONLY IF this object and all of its (deep) members are not managed by a soap context AND the deep structure is a tree (no cycles and co-referenced objects by way of multiple (non-smart) pointers pointing to the same data).
Can be safely used after
delete the deep copy. Does not delete the object itself.
When in C++ mode, soapcpp2 tool adds several methods to classes in addition to adding a default constructor and destructor (when these were not explicitly declared).
The public methods added to a class
a unique type ID (
numeric ID can be used to distinguish base from derived instances.
all data members to default values.
by analyzing its (cyclic) structures.
Requires
return error code or
a new object of type
and not managed by a soap context.
option
this object by deep copying, replicating all deep cycles and shared pointers when a managing soap context is provided as argument. Deep copy is a tree when argument is NULL, but the presence of deep cycles will lead to non-termination. Use flag
the managing context to copy into a tree without cycles and pointers to shared objects.
option
members of this object by deep deletion ONLY IF this object and all of its (deep) members are not managed by a soap context AND the deep structure is a tree (no cycles and co-referenced objects by way of multiple (non-smart) pointers pointing to the same data).
Can be safely used after
delete the deep copy. Does not delete the object itself.
Also for C++, there are four variations of
class/struct/template type
auto-generates to create instances on a context-managed heap:
a new instance of
member initializations that are set with the soapcpp2 auto-generated
was not replaced by a user-defined default constructor.
an array of
Similar to the above, instances are initialized.
a new instance of
data members to the values specified in
The required data members are those with nonzero minOccurs, see the subsections on (smart) pointer members and their
occurrence constraints and container members and their occurrence constraints.
a new instance of
data members to the values specified in
The above functions can be invoked with a NULL
but we will be responsible to use
remove this instance from the unmanaged heap.
class
ArrayOfT{
public:
T *__ptr;
// array pointer
int __size;
// array size
};
where
A multidimensional SOAP Array is:
class
ArrayOfT{
public:
T *__ptr;
// array pointer
int __size
;
// array size of each dimension
};
where
dimensions. The pointer points to an array of
This maps to a complexType restriction of SOAP-ENC:Array in the soapcpp2-generated schema:
The name of the class can be arbitrary. We often use
a prefix to distinguish arrays from other classes and structs.
With SOAP 1.1 encoding, an optional offset member can be added that controls the start of the index range for each dimension:
class
ArrayOfT{
public:
T *__ptr;
// array pointer
int __size
;
// array size of each dimension
int __offset
;
// array offsets to start each dimension
};
For example, we can define a matrix of floats as follows:
class
Matrix
{
public:
double *__ptr;
int __size[2];
};
The following code populates the matrix and serializes it in XML:
soap *soap = soap_new1(SOAP_XML_INDENT);
Matrix A;
double a[6] = { 1, 2, 3, 4, 5, 6 };
A.__ptr = a;
A.__size[0] = 2;
A.__size[1] = 3;
soap_write_Matrix(soap, &A);
Matrix A is serialized as an array with 2x3 values:
when the pointer type is
class
xsd__hexBinary
{
public:
unsigned
char *__ptr;
// points to raw binary data
int __size;
// size of data
};
and
class
xsd__base64Binary
{
public:
unsigned
char *__ptr;
// points to raw binary data
int __size;
// size of data
};
//gsoap xop schema import: http://www.w3.org/2004/08/xop/include class
_xop__Include
{
public:
unsigned
char *__ptr;
// points to raw binary data
int __size;
// size of data
char *id;
// NULL to generate an id, or set to a unique UUID
char *type;
// MIME type of the data
char *options;
// optional description of MIME attachment
};
Attachments are beyond the scope of this document. The
flag must be set to enable attachments. See the gSOAP user guide for more details.
class
ns__simple
{
public:
T __item;
};
The type
numeric and string types),
and custom serializers, such as
This maps to a complexType with simpleContent in the soapcpp2-generated schema:
A wrapper class/struct may include any number of attributes declared with
node and
node:
#import "dom.h"
class
ns__record
{
public:
@xsd__anyAttribute attributes;
// list of DOM attributes
...
xsd__anyType *name;
// optional DOM element
};
where
a DOM node set and
list of all visibly rendered attributes. The name
arbitrary and any name will suffice.
You should place the
at the end of the struct or class. This ensures that the DOM members are populated last as a "catch all". A member name starting with double underscore is a wildcard member name and matches any XML tag. These members are placed at the end of a struct or class
automatically by soapcpp2.
An
added by wsdl2h with option
DOM nodes, and also to populate
content:
#import "dom.h"
class
ns__record
{
public:
...
@xsd__anyAttribute __anyAttribute;
// optional DOM attributes
std::vector<xsd__anyType> __any 0;
// optional DOM elements
xsd__anyType __mixed 0;
// optional mixed content
};
where the members prefixed with
"invisible" to the XML parser, meaning that these members are not bound to XML tag names.
In C you can use a dynamic arrary instead of
#import "dom.h"
struct
ns__record
{
...
@xsd__anyAttribute __anyAttribute;
// optional DOM attributes
$int __sizeOfany;
// size of the array
xsd__anyType *__any;
// optional DOM elements
xsd__anyType __mixed 0;
// optional mixed content
};
Classes can inherit DOM, which enables full use of polymorphism with one base DOM class:
#import "dom.h"
class
ns__record : public xsd__anyType
{
...
std::vector<xsd__anyType*> array;
// array of objects of any class
};
This permits an
to refer to a derived class such as
which will be serialized with an
that is set to "ns:record". The
add the necessary type information to distinguish the XML content from the DOM base type. This is important for the receiving end: without
with type names, only base DOM objects are recognized and instantiated.
Because C lacks OOP principles such as class inheritance and polymorphism, you will need to use the special `void*`
members to serialize data pointed to by a
To ensure that wsdl2h generates pointer-based
nodes with option
add the following line to
This lets wsdl2h produce class/struct members and containers with
of
to be pointer-based, declare in
If you use wsdl2h with option
option
DOM as shown above. Without option
an
serve as the root type in the type hierarchy:
class
xsd__anyType {
_XML __item; struct soap *soap; };
class
ns__record : public xsd__anyType
{
...
};
where the
any XML content as a literal XML string.
To use the DOM API, compile
C++), or link with
C++).
See alsoDocumentation of XML DOM and XPath for more details.
the gSOAP header file with the data binding interface for soapcpp2. These directives are used to configure the code generated by soapcpp2 by declaring various. properties of Web services and XML schemas. When using the wsdl2h tool, you will notice that wsdl2h
generates directives automatically based on the WSDL and XSD input.
Service directives are applicable to service and operations described by WSDL. Schema directives are applicable to types, elements, and attributes defined by XML schemas.
//gsoap <prefix> service <property>: <value>
where
prefix of a service binding. The
are one of the following:
The service
are required in order to generate a valid WSDL with soapcpp2. The other properties are optional.
The
defaults are changed with soapcpp2 option
respectively.
The
default (SOAP 1.1). Protocol property values are:
You can bind service operations to the WSDL namespace of a service by using the namespace prefix as part of the identifier name of the function that defines the service operation:
int prefix__func(arg1, arg2, ..., argn, result);
You can override the
URL at runtime in the auto-generated
call (C/C++ client side) and in the C++ proxy class service call.
A service method directive is of the form:
//gsoap <prefix> service method-<property>: <method> <value>
where
prefix of a service binding and
the unqualified name of a service operation. The
are one of the following:
The
can be repeated for a service operation to declare multiple SOAP Header parts that the service operation requires. You can use
differentiate between request and response messages.
The
repeated for a service operation to declare multiple faults that the service operation may return.
The
two purposes:
To set the SOAPAction header for SOAP protocols, i.e. sets the definitions/binding/operation/SOAP:operation/@soapAction.
To set the URL query string for endpoints with REST protocols, i.e. sets the definitions/binding/operation/HTTP:operation/@location, which specifies a URL query string (starts with a
to complete the service endpoint URL or extends the endpoint URL with a local path (starts with a
Use
differentiate the SOAPAction between SOAP request and response messages.
You can always override the port endpoint URL and action values at runtime in the auto-generated
call (C/C++ client side) and in the auto-generated C++ proxy class service calls. A runtime NULL endpoint URL and/or action uses the defaults set by these directives.
The
two purposes:
To set the type of MIME/MTOM attachments used with SOAP protocols. Multiple attachment types can be declared for a SOAP service operation, i.e. adds definitions/binding/operation/input/MIME:multipartRelated/MIME:part/MIME:content/@type for each type specified.
To set the MIME type of a REST operation. This replaces XML declared in WSDL by definitions/binding/operation/(input|output)/MIME:mimeXml with MIME:content/@type. Use
REST POST and PUT protocols to send encoded form data automatically instead of XML. Only primitive type values can be transmitted with form data, such as numbers and strings, i.e. only types that are legal to use as attributes
members.
Use
differentiate the attachment types between SOAP request and response messages.
//gsoap <prefix> schema <property>: <value>
where
prefix of a schema. The
are one of the following:
To learn more about the local form defaults, see qualified and unqualified members.
The
soapcpp2 option
//gsoap <prefix> schema type-<property>: <name> <value>
//gsoap <prefix> schema type-<property>: <name>::<member> <value>
where
prefix of a schema and
unqualified name of a C/C++ type, and the optional
a class/struct members or enum constant.
You can describe a type:
For example, you can add a description to an enumeration:
//gsoap ns schema type: Vowels The letters A, E, I, O, U, and sometimes Y
//gsoap ns schema type: Vowels::Y A vowel, sometimes
enum class ns__Vowels : char { A =
'A', E =
'E', I = 'I', O =
'O', U =
'U', Y = 'Y' };
This documented enumeration maps to a simpleType restriction of
the soapcpp2-generated schema:
There are several options to choose from to serialize data in XML. The choice depends on the use of the SOAP protocol or if SOAP is not required. The wsdl2h tool automates this for you by taking the WSDL transport bindings into account when generating the
service functions in C and C++ that use SOAP or REST.
The gSOAP tools are not limited to SOAP. The tools implement generic XML data bindings for SOAP, REST, and other uses of XML. So you can read and write XML using the serializing operations
on classes and structs.
The following sections briefly explain the serialization rules with respect to the SOAP protocol for XML Web services. A basic understanding of the SOAP protocol is useful when developing client and server applications that must interoperate with other SOAP
applications.
SOAP/REST Web service client and service operations are represented as functions in your gSOAP header file with the data binding interface for soapcpp2. The soapcpp2 tool will translate these function to client-side service invocation calls and server-side
service operation dispatchers.
A discussion of SOAP clients and servers is beyond the scope of this document. However, the SOAP options discussed here also apply to SOAP client and server development.
in the wsdl:binding section of a WSDL is either "document" or "rpc". The "rpc" style refers to SOAP RPC (Remote Procedure Call), which is more restrictive than the "document" style by requiring one XML element in the SOAP Body to act as the procedure name
with XML subelements as its parameters.
For example, the following directives in the gSOAP header file for soapcpp2 declare that
a SOAP RPC encoding service method:
//gsoap ns service namespace: urn:DB
//gsoap ns service method-protocol: DBupdate SOAP
//gsoap ns service method-style: DBupdate rpc
int ns__DBupdate(...);
The XML payload has a SOAP envelope, optional SOAP header, and a SOAP body with one element representing the operation with the parameters as subelements:
The "document" style puts no restrictions on the SOAP Body content. However, we recommend that the first element's tag name in the SOAP Body should be unique to each type of operation, so that the receiver can dispatch the operation based on this element's
tag name. Alternatively, the HTTP URL path can be used to specify the operation, or the HTTP action header can be used to dispatch operations automatically on the server side (soapcpp2 options -a and -A).
in the wsdl:binding section of a WSDL is either "literal" or "encoded". The "encoded" use refers to the SOAP encoding rules that support id-ref multi-referenced elements to serialize data as graphs.
SOAP encoding is very useful if the data internally forms a graph (including cycles) and we want the graph to be serialized in XML in a format that ensures that its structure is preserved. In that case, SOAP 1.2 encoding is the best option.
SOAP encoding also adds encoding rules for SOAP arrays to serialize multi-dimensional arrays. The use of XML
attributes to exchange XML data in SOAP encoding is not permitted. The only attributes permitted are the standard XSD attributes, SOAP encoding attributes (such as for arrays), and id-ref.
For example, the following directives in the gSOAP header file for soapcpp2 declare that
a SOAP RPC encoding service method:
//gsoap ns service namespace: urn:DB
//gsoap ns service method-protocol: DBupdate SOAP
//gsoap ns service method-style: DBupdate rpc
//gsoap ns service method-encoding: DBupdate encoded
int ns__DBupdate(...);
The XML payload has a SOAP envelope, optional SOAP header, and a SOAP body with an encodingStyle attribute for SOAP 1.1 encoding and an element representing the operation with parameters that are SOAP 1.1 encoded:
Note that the name "Joe" is shared by two records and the string is referenced by SOAP 1.1 href and id attributes.
While gSOAP only introduces multi-referenced elements in the payload when they are actually multi-referenced in the data graph, other SOAP applications may render multi-referenced elements more aggressively. The example could also be rendered as:
SOAP 1.2 encoding is cleaner and produces more accurate XML encodings of data graphs by setting the id attribute on the element that is referenced:
NoteSome SOAP 1.2 applications consider the namespace
The gSOAP SOAP 1.2 encoding serialization follows the 2007 standard, while accepting unqualified id and ref attributes.
To remove all rendered id-ref multi-referenced elements in gSOAP, use the
to initialize the gSOAP engine context.
Some XML validation rules are turned off with SOAP encoding, because of the presence of additional attributes, such as id and ref/href, SOAP arrays with arbitrary element tags for array elements, and the occurrence of additional multi-ref elements in the
SOAP 1.1 Body.
The use of "literal" puts no restrictions on the XML in the SOAP Body. Full XML validation is possible, which can be enabled with the
to initialize the gSOAP engine context. However, data graphs will be serialized as trees and cycles in the data will be cut from the XML rendition.
//gsoap ns service method-protocol: DBupdate SOAP1.2
The gSOAP soapcpp2 auto-generates client and server code. At the client side, this operation sends data with SOAP 1.2 but accepts responses also in SOAP 1.1. At the server side, this operation accepts requests in SOAP 1.1 and 1.2 and will return responses
in the same SOAP version.
As we discussed in the previous section, the SOAP 1.2 protocol has a cleaner multi-referenced element serialization format that greatly enhances the accuracy of data graph serialization with SOAP RPC encoding and is therefore recommended.
The SOAP 1.2 protocol default can also be set by importing and loading
#import "soap12.h"
data is put on the heap and managed by the gSOAP engine context
You can read and write XML directly to a file or stream with the serializing operations on classes and structs.
To define and use XML Web service client and service operations, we can declare these operations in your gSOAP header file with the data binding interface for soapcpp2 as functions. The function are translated by soapcpp2 to client-side service invocation
calls and server-side service operation dispatchers.
The REST operations POST, GET, and PUT are declared with
in the gSOAP header file for soapcpp2. For example, a REST POST operation is declared as follows:
//gsoap ns service namespace: urn:DB
//gsoap ns service method-protocol: DBupdate POSTint ns__DBupdate(...);
There is no SOAP Envelope and no SOAP Body in the payload for
Also the XML serialization rules are identical to SOAP document/literal. The XML payload only has the operation name as an element with its parameters serialized as subelements:
To force id-ref serialization with REST similar to SOAP 1.2 multi-reference encoding, use the
to initialize the gSOAP engine context. The XML serialization includes id and ref attributes for multi-referenced elements as follows:
soap->recvfd = fd;
// an int file descriptor to read from (0 by default)
soap->sendfd = fd;
// an int file descriptor to write to (1 by default)
soap->is = &is;
// C++ only: a std::istream is object to read from
soap->os = &os;
// C++ only: a std::ostream os object to write to
soap->is = cs;
// C only: a const char* string to read from (soap->is will advance)
soap->os = &cs;
// C only: pointer to a const char*, will be set to point to the string output
Normally, all of these context members are NULL, which is required to send and receive data over sockets by gSOAP clients and servers. Therefore, if you set any of these context members in a client or server application then you MUST reset them to NULL to
ensure that socket communications are not blocked.
Note: the use of
C requires gSOAP 2.8.28 or later.
In the following sections, we present more details on how to read and write to files and streams, and use string buffers as sources and sinks for XML data.
In addition, you can set IO callback functions to handle IO at a lower level.
For more details, see the gSOAP user guide.
FILE *fp = fopen("record.xml",
"r");
if (fp != NULL)
{
soap->recvfd = fileno(fp);
// get file descriptor of file to read from
if (soap_read_ns__record(soap, &pers1))
... // handle IO error
fclose(fp);
soap->recvfd = 0;
// read from stdin, or -1 to block reading
}
FILE *fp = fopen("record.xml",
"w");
if (fp != NULL)
{
soap->sendfd = fileno(fp);
// get file descriptor of file to write to
if (soap_write_ns__record(soap, &pers1))
... // handle IO error
fclose(fp);
soap->sendfd = 1;
// write to stdout, or -1 to block writing
}
Similar code with streams in C++:
#include <fstream>
std::fstream fs;
fs.open("record.xml", std::ios::in);
if (fs)
{
soap->is = &fs;
if (soap_read__ns__record(soap, &pers1))
... // handle IO error
fs.close();
soap->is = NULL;
}
fs.open("record.xml", std::ios::out);
if (fs)
{
soap->os = &fs;
if (soap_write__ns__record(soap, &pers1))
... // handle IO error
fs.close();
soap->os = NULL;
}
from
following example:
#include <sstream>
std::stringstream ss;
ss.str("...");
// XML to parse
soap->is = &ss;
if (soap_read__ns__record(soap, &pers1))
... // handle IO error
soap->is = NULL;
soap->os = &ss;
if (soap_write__ns__record(soap, &pers1))
... // handle IO error
soap->os = NULL;
std::string s = ss.str();
// string with XML
For C we can use
point to strings of XML content as follows (this requires gSOAP 2.8.28 or later):
soap->is =
"..."; // XML to parse
if (soap_read__ns__record(soap, &pers1))
... // handle IO error
soap->is = NULL;
const
char *cs = NULL;
soap->os = &cs;
if (soap_write__ns__record(soap, &pers1))
... // handle IO error
soap->os = NULL;
... = cs;
// string with XML (do not free(cs): managed by the context and freed with soap_end())
Note that
a
set by the managing context to point to the XML data that is stored on the context-managed heap.
For earlier gSOAP versions we recommend to use IO callbacks
see the gSOAP user guide.
enables us to allocate data in context-managed heap space that can be collectively deleted. All deserialized data is placed on the context-managed heap by the gSOAP engine.
option
data on a context-managed heap with:
You can also make shallow copies of data with
uses
of
length
This function returns a pointer to the copy. This function requires gSOAP 2.8.27 or later.
The
around
the
heap allocations for collective deletion with
#include "soapH.h"
#include "ns.nsmap"
...
struct soap *soap = soap_new();
// new context
...
struct ns__record *record = soap_malloc(soap,
sizeof(struct ns__record));
soap_default_ns__record(soap, record);
// auto-generated struct initializer
...
soap_destroy(soap);
// only for C++, see section on C++ below
soap_end(soap);
// delete record and all other heap allocations
soap_free(soap);
// delete context
The soapcpp2 auto-generated deserializers in C use
allocate and populate deserialized structures, which are managed by the context for collective deletion.
To make
copies to the context-managed heap, we can use the functions:
If your C compiler supports
you can use the following macro to simplify the managed heap allocation and initialization of primitive values:
#define soap_assign(soap, lhs, rhs) (*(lhs = (typeof(lhs))soap_malloc(soap, sizeof(*lhs))) = rhs)
Pointers to primitive values are often used for optional members. For example, assume we have the following struct:
struct
ns__record
{
const
char *name;
// required name
uint64_t *SSN;
// optional SSN
struct
ns__record *spouse; // optional spouse
};
Use
on the managed heap:
struct soap *soap = soap_new();
// new context
...
struct ns__record *record = soap_malloc(soap,
sizeof(struct ns__record));
soap_default_ns__record(soap, record);
record->name = soap_strdup(soap,
"Joe");
soap_assign(soap, record->SSN, 1234567890LL);
...
soap_end(soap);
// delete managed soap_malloc'ed heap data
soap_free(soap);
// delete context
Without the
will need two lines of code, one to allocate and one to assign (you should also use this if your system can run out of memory):
assert((record->SSN = (uint64_t*)soap_malloc(soap,
sizeof(utint64_t))) != NULL);
*record->SSN = 1234567890LL;
The gSOAP serializer can serialize any heap, stack, or static allocated data. So we can also create a new record as follows:
struct soap *soap = soap_new();
// new context
...
struct ns__record *record = soap_malloc(soap,
sizeof(struct ns__record));
static uint64_t SSN = 1234567890LL;
soap_default_ns__record(soap, record);
record->name =
"Joe";
record->SSN = &SSN;
// safe to use static values: the value of record->SSN is never changed by gSOAP
...
soap_end(soap);
// delete managed soap_malloc'ed heap data
soap_free(soap);
// delete context
Use the soapcpp2 auto-generated
to duplicate data into another context (this requires soapcpp2 option
generate), here shown for C with the second argument
because we want to allocate a new managed structure:
struct soap *other_soap = soap_new();
// another context
struct
ns__record *other_record = soap_dup_ns__record(other_soap, NULL, record);
...
soap_destroy(other_soap);
// only for C++, see section on C++ below
soap_end(other_soap);
// delete other_record and all of its deep data
soap_free(other_soap);
// delete context
Note that the only reason to use another context and not to use the primary context is when the primary context must be destroyed together with all of the objects it manages while some of the objects must be kept alive. If the objects that are kept alive
contain deep cycles then this is the only option we have, because deep copy with a managing context detects and preserves these cycles unless the
is used with the context:
struct soap *other_soap = soap_new1(SOAP_XML_TREE);
// another context
struct
ns__record *other_record = soap_dup_ns__record(other_soap, NULL, record);
The resulting deep copy will be a full copy of the source data structure as a tree without co-referenced data (i.e. no digraph) and without cycles. Cycles are pruned and (one of the) pointers that forms a cycle is repaced by NULL.
You can also deep copy into unmanaged space and use the auto-generated
(requires soapcpp2 option
to delete it later, but you MUST NOT do this for any data that has deep cycles in its runtime data structure:
struct
ns__record *other_record = soap_dup_ns__record(NULL, NULL, record);
...
soap_del_ns__record(other_record);
// deep delete record data members
free(other_record);
// delete the record
Cycles in the data structure will lead to non-termination when making unmanaged deep copies. Consider for example:
struct
ns__record
{
const
char *name;
// required name
uint64_t SSN;
// required SSN
struct
ns__record *spouse; // optional spouse
};
The code to populate a structure with a mutual spouse relationship:
struct soap *soap = soap_new();
...
struct ns__record pers1, pers2;
soap_default_ns__record(soap, &pers1);
soap_default_ns__record(soap, &pers2);
pers1.name =
"Joe"; // OK to serialize static data
pers1.SSN = 1234567890;
pers1.spouse = &pers2;
pers2.name = soap_strdup(soap,
"Jane"); // allocates and copies a string
pers2.SSN = 1987654320;
pers2.spouse = &pers1;
...
struct ns__record *pers3 = soap_dup_ns__record(NULL, NULL, &pers1);
// BAD
struct
ns__record *pers4 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
soap_set_mode(soap, SOAP_XML_TREE);
struct
ns__record *pers5 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
As we can see, the gSOAP serializer can serialize any heap, stack, or static allocated data, such as in the code above. So we can serialize the stack-allocated
as follows:
FILE *fp = fopen("record.xml",
"w");
if (fp != NULL)
{
soap->sendfd = fileno(fp);
// file descriptor to write to
soap_set_mode(soap, SOAP_XML_GRAPH);
// support id-ref w/o requiring SOAP
soap_clr_mode(soap, SOAP_XML_TREE);
// if set, clear
soap_write_ns__record(soap, &pers1);
fclose(fp);
soap->sendfd = -1;
// block further writing
}
which produces an XML document record.xml that is similar to:
Deserialization of an XML document with a SOAP 1.1/1.2 encoded id-ref graph leads to the same non-termination problem when we later try to copy the data into unmanaged space:
struct soap *soap = soap_new1(SOAP_XML_GRAPH);
// support id-ref w/o SOAP
...
struct ns__record pers1;
FILE *fp = fopen("record.xml",
"r");
if (fp != NULL)
{
soap->recvfd = fileno(fp);
if (soap_read_ns__record(soap, &pers1))
... // handle IO error
fclose(fp);
soap->recvfd = -1;
// blocks further reading
}
...
struct ns__record *pers3 = soap_dup_ns__record(NULL, NULL, &pers1);
// BAD
struct
ns__record *pers4 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
soap_set_mode(soap, SOAP_XML_TREE);
struct
ns__record *pers5 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
Copying data with
managed space is always safe. Copying into unmanaged space requires diligence. But deleting unmanaged data is easy with
You can also use
delete structures that you created in C, but only if these structures are created with
do NOT contain pointers to stack and static data.
where
or class template (container or smart pointer). Heap allocation is tracked by the
Only structs, classes, and class templates are allocated with
There are four variations of
class/struct/template type
auto-generates to create instances on a context-managed heap:
a new instance of
member initializations that are set with the soapcpp2 auto-generated
was not replaced by a user-defined default constructor.
an array of
Similar to the above, instances are initialized.
a new instance of
data members to the values specified in
The required data members are those with nonzero minOccurs, see the subsections on (smart) pointer members and their
occurrence constraints and container members and their occurrence constraints.
a new instance of
data members to the values specified in
The above functions can be invoked with a NULL
but you are responsible to use
remove this instance from the unmanaged heap.
For example, to allocate a managed
can use:
std::string *s =
soap_new_std__string(soap);
Primitive types and arrays of these are allocated with
the gSOAP engine. As we stated above, all types except for classes, structs, class templates (containers and smart pointers) are allocated with
reasons of efficiency.
You can use a C++ template to simplify the managed allocation and initialization of primitive values as follows (this is for primitive types only, because structs and classes are allocated with
template<class T>
T * soap_make(struct soap *soap, T val)
{
T *p = (T*)soap_malloc(soap,
sizeof(T));
if (p)
// out of memory? Can also guard with assert(p != NULL) or throw an error
*p = val;
return p;
}
For example, assuming we have the following class:
class
ns__record
{
public:
std::string name;
// required name
uint64_t *SSN;
// optional SSN
ns__record *spouse;
// optional spouse
};
You can instantiate a record by using the auto-generated
use
on the managed heap:
soap *soap = soap_new();
// new context
...
ns__record *record = soap_new_set_ns__record(
soap,
"Joe",
soap_make<uint64_t>(soap, 1234567890LL),
NULL);
...
soap_destroy(soap);
// delete record and all other managed instances
soap_end(soap);
// delete managed soap_malloc'ed heap data
soap_free(soap);
// delete context
Note however that the gSOAP serializer can serialize any heap, stack, or static allocated data. So we can also create a new record as follows:
uint64_t SSN = 1234567890LL;
ns__record *record = soap_new_set_ns__record(soap,
"Joe", &SSN, NULL);
which will be fine to serialize this record as long as the local
value remains in scope when invoking the serializer and/or using
It does not matter if
called beyond the scope of
To facilitate class methods to access the managing context, we can add a soap context pointer to a class/struct:
class
ns__record
{
...
void create_more();
// needs a context to create more internal data
protected:
struct soap *soap; // the context that manages this instance, or NULL
};
The context is set when invoking
similar) with a non-NULL context argument.
Use the soapcpp2 auto-generated
to duplicate data into another context (this requires soapcpp2 option
generate), here shown for C++ with the second argument
to allocate a new managed object:
soap *other_soap = soap_new();
// another context
ns__record *other_record = soap_dup_ns__record(other_soap, NULL, record);
...
soap_destroy(other_soap);
// delete record and other managed instances
soap_end(other_soap);
// delete other data (the SSNs on the heap)
soap_free(other_soap);
// delete context
To duplicate base and derived instances when a base class pointer or reference is provided, use the auto-generated method
soap *other_soap = soap_new();
// another context
ns__record *other_record = record->soap_dup(other_soap);
...
soap_destroy(other_soap);
// delete record and other managed instances
soap_end(other_soap);
// delete other data (the SSNs on the heap)
soap_free(other_soap);
// delete context
Note that the only reason to use another context and not to use the primary context is when the primary context must be destroyed together with all of the objects it manages while some of the objects must be kept alive. If the objects that are kept alive
contain deep cycles then this is the only option we have, because deep copy with a managing context detects and preserves these cycles unless the
is used with the context:
soap *other_soap = soap_new1(SOAP_XML_TREE);
// another context
ns__record *other_record = record->soap_dup(other_soap);
// deep tree copy
The resulting deep copy will be a full copy of the source data structure as a tree without co-referenced data (i.e. no digraph) and without cycles. Cycles are pruned and (one of the) pointers that forms a cycle is repaced by NULL.
You can also deep copy into unmanaged space and use the auto-generated
or the
soapcpp2 option
delete it later, but we MUST NOT do this for any data that has deep cycles in its runtime data structure graph:
ns__record *other_record = record->soap_dup(NULL);
...
other_record->soap_del();
// deep delete record data members
delete other_record;
// delete the record
Cycles in the data structure will lead to non-termination when making unmanaged deep copies. Consider for example:
class
ns__record
{
const
char *name;
// required name
uint64_t SSN;
// required SSN
ns__record *spouse;
// optional spouse
};
The code to populate a structure with a mutual spouse relationship:
soap *soap = soap_new();
...
ns__record pers1, pers2;
pers1.name =
"Joe";
pers1.SSN = 1234567890;
pers1.spouse = &pers2;
pers2.name =
"Jane";
pers2.SSN = 1987654320;
pers2.spouse = &pers1;
...
ns__record *pers3 = soap_dup_ns__record(NULL, NULL, &pers1);
// BAD
ns__record *pers4 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
soap_set_mode(soap, SOAP_XML_TREE);
ns__record *pers5 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
Note that the gSOAP serializer can serialize any heap, stack, or static allocated data, such as in the code above. So we can serialize the stack-allocated
as follows:
FILE *fp = fopen("record.xml",
"w");
if (fp != NULL)
{
soap->sendfd = fileno(fp);
// file descriptor to write to
soap_set_mode(soap, SOAP_XML_GRAPH);
// support id-ref w/o requiring SOAP
soap_clr_mode(soap, SOAP_XML_TREE);
// if set, clear
if (soap_write_ns__record(soap, &pers1))
... // handle IO error
fclose(fp);
soap->sendfd = -1;
// block further writing
}
which produces an XML document record.xml that is similar to:
Deserialization of an XML document with a SOAP 1.1/1.2 encoded id-ref graph leads to the same non-termination problem when we later try to copy the data into unmanaged space:
soap *soap = soap_new1(SOAP_XML_GRAPH);
// support id-ref w/o SOAP
...
ns__record pers1;
FILE *fp = fopen("record.xml",
"r");
if (fp != NULL)
{
soap->recvfd = fileno(fp);
// file descriptor to read from
if (soap_read_ns__record(soap, &pers1))
... // handle IO error
fclose(fp);
soap->recvfd = -1;
// block further reading
}
...
ns__record *pers3 = soap_dup_ns__record(NULL, NULL, &pers1);
// BAD
ns__record *pers4 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
soap_set_mode(soap, SOAP_XML_TREE);
ns__record *pers5 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
Copying data with
managed space is always safe. Copying into unmanaged space requires diligence. But deleting unmanaged data is easy with
You can also use
delete structures in C++, but only if these structures are created with
anything else, and the structures do NOT contain pointers to stack and static data.
heap allocation of contexts:
struct soap *soap = soap_new1(<flag> | <flag> ... | <flag>);
,,,
soap_destroy(soap);
// delete objects
soap_end(soap);
// delete other data and temp data
soap_free(soap);
// free context
and with
allocated contexts:
struct soap soap;
soap_init1(&soap, <flag> | <flag> ... | <flag>);
,,,
soap_destroy(&soap);
// delete objects
soap_end(&soap);
// delete other data and temp data
soap_done(&soap);
// clear context
where
to contain UTF-8 content. This option is recommended.
as if they were NULL pointers, i.e. omits elements and attributes when empty.
XML while deserializing. Should not be used together with SOAP 1.1/1.2 encoding style of messaging. Use soapcpp2 option
hard code
serializers. Not recommended with SOAP 1.1/1.2 encoding style messaging.
XML.
removes unused
them to appropriate places by applying c14n normalization rules. Should not be used together with SOAP 1.1/1.2 encoding style messaging.
id-ref, while pruning data structure cycles to prevent nontermination of the serializer for cyclic structures.
and cyclic graphs with shared pointers to objects) using id-ref attributes. That is, XML with SOAP multi-ref encoded id-ref elements. This is a structure-preserving serialization format, because co-referenced data and also cyclic relations are accurately represented.
namespace declarations, assuming that the schema attribute form is "qualified" by default (be warned if it is not, since attributes in the null namespace will get bound to namespaces!).
with
serialized.
ignores XML namespaces, i.e. element and attribute tag names match independent of their namespace.
This option is usually not needed unless the receiver rejects all
This option may affect the quality of the deserializer, which relies on
to distinguish base class instances from derived class instances transported in the XML payloads.
transfers.
outbound messages.
requires compiling with
linking with zlib (
see MIME/MTOM attachment binary types.
see MIME/MTOM attachment binary types.
Make sure to
your code and also define a namespace table or
the namespace prefix for services.
Use soapcpp2 option -j (C++ only) to generate C++ proxy and service objects. The auto-generated files include documented inferfaces. Compile with soapC.cpp and link with -lgsoap++, or alternatively compile stdsoap2.cpp.
Without soapcpp2 option -j: client-side uses the auto-generated soapClient.cpp and soapC.cpp (or C versions of those). Compile and link with -lgsoap++ (-lgsoap for C), or alternatively compile stdsoap2.cpp (stdsoap2.c for C).
Without soapcpp2 option -j: server-side uses the auto-generated soapServer.cpp and soapC.cpp (or C versions of those). Compile and link with -lgsoap++ (-lgsoap for C), or alternatively compile stdsoap2.cpp (stdsoap2.c for C).
Use
Use
Additional notes with respect to the wsdl2h and soapcpp2 tools:
Nested classes, structs, and unions in a gSOAP header file are unnested by soapcpp2.
Use
import other header files in a gSOAP header file for soapcpp2. The
and
but are moved to the very start of the generated code for the C/C++ compiler to include before all generated definitions. Often it is useful to add an
a volatile type that includes the actual type declaration, and to ensure transient types are declared when these
are used in a data binding interface declared in a gSOAP header file for soapcpp2.
To remove any SOAP-specific bindings, use soapcpp2 option
A gSOAP header file for soapcpp2 should not include any code statements, only data type declarations. This includes constructor initialization lists that are not permitted. Use member initializations instead.
C++ namespaces are supported. Use wsdl2h option
Or add a
the header file, but the
Optional XML DOM support can be used to store mixed content or literal XML content. Otherwise, mixed content may be lost. Use wsdl2h option
XML DOM support and compile and link with
For details, see XML DOM and XPath.
that includes two bindings for SOAP namespaces. We can remove all SOAP namespaces (and SOAP processing logic) with soapcpp2 option
by simply setting the two entries to NULL:
struct
Namespace namespaces[] =
{
{"SOAP-ENV", NULL, NULL, NULL},
{"SOAP-ENC", NULL, NULL, NULL},
...
};
Note that once the
you can copy-paste the content into your project code. However, if we rerun wsdl2h on updated WSDL/XSD files or
then we need to use the updated table.
In cases that no XML namespaces are used at all, for example with XML-RPC, you may use an empty namespace table:
struct
Namespace namespaces[] = {{NULL,NULL,NULL,NULL}};
However, beware that any built-in xsi attributes that are rendered will lack the proper namespace binding. At least we suggest to use
this reason.
book app (reads/writes address.xml file)
prefix name preference for wsdl2h
binding (tree, digraph, cyclic graph)
graph serialization as tree, digraph, and cyclic
data binding definitions from address.xsd
data binding definitions
by address app
data binding definitions
mapping table
Option
(root) elements in addition to types. In this case the root element
bound to
The complexType
to class
which is also the type of
This option is not required, but allows you to use global element tag names when referring to their serializers, instead of their type name. Option
the SOAP protocol. Options
client and server code generation. Option
the output
See the
and related pages.
The
the XML namespace prefix for the bindings:
The DOB field is a
which is bound to
To change this to
the import of the
serializer by uncommenting the definition of
Then change
the code.
Building the graph serialization example:
To compile without using the
simply compile
with the above.
To execute the Graph serialization example:
Copyright (C) 2016, Robert van Engelen, Genivia Inc., All Rights Reserved.
Converted on Wed Mar 2 2016 10:24:54 by Doxygen 1.8.10
Introduction
This is a detailed overview of the gSOAP XML data bindings concepts, usage, and implementation. At the end of this document two examples are given to illustrate the application of XML data bindings.The first simple example
address.cppshows
how to use wsdl2h to bind an XML schema to C++. The C++ application reads and writes an XML file into and from a C++ "address book" data structure. The C++ data structure is an STL vector of address objects.
The second example
graph.cppshows
how XML is serialized as a tree, digraph, and cyclic graph. The digraph and cyclic graph serialization rules are similar to SOAP 1.1/1.2 encoded multi-ref elements with id-ref attributes to link elements through IDREF XML references, creating a an XML graph
with pointers to XML nodes.
These examples demonstrate XML data bindings only for relatively simple data structures and types. The gSOAP tools support more than just these type of structures to serialize in XML. There are practically no limits to enable XML serialization of C and C++
types.
Support for XML schema components is unlimited. The wsdl2h tool maps schemas to C and C++ using built-in intuitive mapping rules, while allowing the mappings to be customized using a
typemap.datfile
with mapping instructions for wsdl2h.
The information in this document is applicable to gSOAP 2.8.26 and higher, which supports C++11 features. However, C++11 is not required to use this material and the examples included, unless we need smart pointers and scoped enumerations. While most of
the examples in this document are given in C++, the concepts also apply to C with the exception of containers, smart pointers, classes and their methods. None of these exceptions limit the use of the gSOAP tools for C in any way.
The data binding concepts described in this document were first envisioned in 1999 by Prof. Robert van Engelen at the Florida State University. An implementation was created in 2000, named "stub/skeleton compiler". The first articles on its successor version
"gSOAP" appeared in 2002. The principle of mapping XSD components to C/C++ types and vice versa is now widely adopted in systems and programming languages, including Java web services and by C# WCF.
We continue to be committed to our goal to empower C/C++ developers with powerful autocoding tools for XML. Our commitment started in the very early days of SOAP by actively participating in SOAP
interoperability testing, participating in the development and testing of the W3C XML Schema Patterns for Databinding Interoperability,
and continues by contributing to the development of OASIS open standards in partnership with leading IT companies.
Mapping WSDL and XML schemas to C/C++
To convert WSDL and XML schemas (XSD files) to code, use the wsdl2h command to generate the data binding interface code that is saved to a special gSOAP header file with WSDL service declarations and the data binding interface:wsdl2h [options] -o file.h ... XSD and WSDL files ...
This command converts WSDL and XSD files to C++ (or pure C with wsdl2h option
-c)
and saves the data binding interface to a gSOAP header file
file.hthat
uses familiar C/C++ syntax extended with
//gsoapdirectives and
annotations. Notational conventions are used in the data binding interface to declare serializable C/C++ types and functions for Web service operations.
The WSDL 1.1/2.0, SOAP 1.1/1.2, and XSD 1.0/1.1 standards are supported by the gSOAP tools. In addition, the most popular WS specifications are also supported, including WS-Addressing, WS-ReliableMessaging, WS-Discovery, WS-Security, WS-Policy, WS-SecurityPolicy,
and WS-SecureConversation.
This document focusses on XML data bindings. XML data bindings for C/C++ bind XML schema types to C/C++ types. So integers in XML are bound to C integers, strings in XML are bound to C or C++ strings, complex types in XML are bound to C structs or C++ classes,
and so on.
A data binding is dual. Either you start with WSDLs and/or XML schemas that are mapped to equivalent C/C++ types, or you start with C/C++ types that are mapped to XSD types. Either way, the end result is that you can serialize C/C++ types in XML such that
your XML is an instance of XML schema(s) and is validated against these schema(s).
This covers all of the following standard XSD components with their optional attributes and properties:
| XSD Component | Attributes and Properties |
|---|---|
| schema | targetNamespace, version, elementFormDefault, attributeFormDefault, defaultAttributes |
| attribute | name, ref, type, use, default, fixed, form, targetNamespace, wsdl:arrayType |
| element | name, ref, type, default, fixed, form, nillable, abstract, substitutionGroup, minOccurs, maxOccurs, targetNamespace |
| simpleType | name |
| complexType | name, abstract, mixed, defaultAttributesApply |
| all | |
| choice | minOccurs, maxOccurs |
| sequence | minOccurs, maxOccurs |
| group | name, ref, minOccurs, maxOccurs |
| attributeGroup | name, ref |
| any | minOccurs, maxOccurs |
| anyAttribute |
| Directive | Description |
|---|---|
| import | Imports a schema into the importing schema for referencing |
| include | Include schema component definitions into a schema |
| override | Override by replacing schema component definitions |
| redefine | Extend or restrict schema component definitions |
| annotation | Annotates a component |
| XSD Facet | Maps to |
|---|---|
| enumeration | enum |
| simpleContent | class/struct wrapper with __itemmember |
| complexContent | class/struct |
| list | enum*bitmask ( enum*enumerates up to 64 bit masks) |
| extension | class/struct inheritance/extension |
| restriction | typedefand class/struct inheritance/redeclaration |
| length | typedefwith restricted content length annotation |
| minLength | typedefwith restricted content length annotation |
| maxLength | typedefwith restricted content length annotation |
| minInclusive | typedefwith numerical value range restriction annotation |
| maxInclusive | typedefwith numerical value range restriction annotation |
| minExclusive | typedefwith numerical value range restriction annotation |
| maxExclusive | typedefwith numerical value range restriction annotation |
| precision | typedefwith pattern annotation (pattern used for output, but input is not validated) |
| scale | typedefwith pattern annotation (pattern used for output, but input is not validated) |
| totalDigits | typedefwith pattern annotation (pattern used for output, but input is not validated) |
| fractionDigits | typedefwith pattern annotation (pattern used for output, but input is not validated) |
| pattern | typedefwith pattern annotation (define soap::fsvalidatecallback to validate patterns) |
| union | string with union of values |
| XSD Type | Maps to |
|---|---|
| any/anyType | _XMLstring with literal XML content (or enable DOM with wsdl2h option -d) |
| anyURI | string (i.e. char*, wchar_t*, std::string, std::wstring) |
| string | string (i.e. char*, wchar_t*, std::string, std::wstring) |
| boolean | bool(C++) or enum xsd__boolean(C) |
| byte | char(i.e. int8_t) |
| short | short(i.e. int16_t) |
| int | int(i.e. int32_t) |
| long | LONG64(i.e. long longand int64_t) |
| unsignedByte | unsigned char(i.e. uint8_t) |
| unsignedShort | unsigned short(i.e. uint16_t) |
| unsignedInt | unsigned int(i.e. uint32_t) |
| unsignedLong | ULONG64(i.e. unsigned long longand uint64_t) |
| float | float |
| double | double |
| integer | string or #import "custom/int128.h"to use 128 bit xsd__integer |
| decimal | string or #import "custom/long_double.h"to use long double |
| precisionDecimal | string |
| duration | string or #import "custom/duration.h"to use 64 bit xsd__duration |
| dateTime | time_tor #import "custom/struct_tm.h"to use struct tmfor xsd__dateTime |
| time | string or #import "custom/long_time.h"to use 64 bit xsd__time |
| date | string or #import "custom/struct_tm_date.h"to use struct tmfor xsd__date |
| hexBinary | special class/struct xsd__hexBinary |
| base64Bianry | special class/struct xsd__base64Binary |
| QName | _QNamestring (URI normalization rules are applied) |
xsd:tokenis
bound to a C++ or C string:
typedef std::string xsd__token;
// C++
typedef
char *xsd__token;
// C (wsdl2h option -c)
This associates a compatible value space to the type with the appropriate XSD type name used by the soapcpp2-generated serializers.
It is possible to remap types by adding the appropriate mapping rules to
typemap.datas
we will explain in more detail in the next section.
Imported custom serializers are intended to extend the C/C++ type bindings when the default binding to string is not satisfactory to your taste and if the target platform supports these C/C++ types. To add custom serializers to
typemap.datfor
wsdl2h, see adding custom serializers below.
Using typemap.dat to customize data bindings
Use atypemap.datfile to redefine
namespace prefixes and to customize type bindings for the the generated header files produced by the wsdl2h tool. The
typemap.datis
the default file processed by wsdl2h. Use wsdl2h option
-tto
specify a different file.
Declarations in
typemap.datcan be
broken up over multiple lines by continuing on the next line by ending each line to be continued with a backslash
\.
The limit is 4095 characters per line, whether the line is broken up or not.
XML namespace bindings
The wsdl2h tool generates C/C++ type declarations that usens1,
ns2,
etc. as schema-binding URI prefixes. These default prefixes are generated somewhat arbitrarily for each schema targetNamespace URI, meaning that their ordering may change depending on the WSDL and XSD order of processing with wsdl2h.
Therefore, it is strongly recommended to declare your own prefix for each schema URI in
typemap.datto
reduce maintaince effort of your code. This is more robust when anticipating possible changes of the schema(s) and/or the binding URI(s) and/or the tooling algorithms.
The first and foremost important thing to do is to define prefix-URI bindings for our C/C++ code by adding the following line(s) to our
typemap.dator
make a copy of this file and add the line(s) that bind our choice of prefix name to each URI:
prefix = "URI"
For example:
g = "urn:graph"
This produces
g__nameC/C++ type
names that are bound to the "urn:graph" schema by association of
gto
the generated C/C++ types.
This means that
<g:name xmlns:g="urn:graph">is
parsed as an instance of a
g__nameC/C++
type. Also
<x:name xmlns:x="urn:graph">parses
as an instance of
g__name, because
the prefix
xhas the same URI value
urn:graph.
Prefixes in XML have local scopes (like variables in a block).
The first run of wsdl2h will reveal the URIs, so you do not need to search WSDLs and XSD files for all of the target namespaces. Just copy them from the generated header file after the first run into
typemap.datfor
editing.
XSD type bindings
Custom C/C++ type bindings can be declared intypemap.datto
associate C/C++ types with specific schema types. These type bindings have four parts:
prefix__type = declaration | use | ptruse
where
prefix__typeis the schema type
to be customized (the
prefix__typename
uses the common double underscore naming convention);
declarationdeclares the C/C++ type
in the wsdl2h-generated header file. This part can be empty if no explicit declaration is needed;
useis an optional part that specifies
how the C/C++ type is used in the code. When omitted, it is the same as
prefix__type;
ptruseis an optional part that
specifies how the type is used as a pointer type. By default it is the
usetype
name with a
*or C++11
std::shared_ptr<>when
enabled (see further below).
For example, to map
xsd:durationto
a
long long(
LONG64)
type that holds millisecond duration values, we can use the custom serializer declared in
custom/duration.hby
adding the following line to
typemap.dat:
xsd__duration = #import "custom/duration.h"
Here, we omitted the second field, because
xsd__durationis
the name that wsdl2h uses to identify and use this type for our code. The third field is omitted to let wsdl2h use
xsd__duration *for pointers or
std::shared_ptr<xsd__duration>if
smart pointers are enabled.
To map
xsd:stringto
wchar_t*wide
strings:
xsd__string = | wchar_t* | wchar_t*
Note that the first field is empty, because
wchar_tis
a C type and does not need to be declared. A
ptrusefield
is given so that we do not end up generating the wrong pointer types, such as
wchar_t**and
std::shared_ptr<wchar_t>.
When the auto-generated declaration should be preserved but the
useor
ptrusefields
replaced, then we use an ellipsis for the declaration part:
prefix__type = ... | use | ptruse
This is useful to map schema polymorphic types to C types for example, where we need to be able to both handle a base type and its extensions as per schema extensibility. Say we have a base type called ns:base that is extended, then we can remap this to
a C type that permits referening the extended types via a
void*as
follows:
ns__base = ... | int __type_base; void*
such that
__type_baseand
void*will
be used to (de)serialize any data type, including base and its derived types. The
__type_baseinteger
is set to a
SOAP_TYPE_Tvalue to indicate
what type of data the
void*pointer
points to.
Custom serializers for XSD types
In the previous part we saw how a custom serializer is used to bindxsd:durationto
a
long long(
LONG64or
int64_t)
type to store millisecond duration values:
xsd__duration = #import "custom/duration.h"
The
xsd__durationtype is an alias
of
long long(
LONG64or
int64_t).
While wsdl2h will use this binding declared in
typemap.datautomatically,
you will also need to compile
custom/duration.c.
Each custom serializer has a header file and an implementation file written in C. You can compile these in C++ (rename files to
.cppif
needed).
We will discuss the custom serializers that are available to you.
xsd:integer
The wsdl2h tool mapsxsd:integerto
a string by default. To map
xsd:integerto
the 128 bit big int type
__int128_t:
xsd__integer = #import "custom/int128.h"
The
xsd__integertype is an alias
of
__int128_t.
WarningBeware that the
xsd:integervalue
space of integers is in principle unbounded and values can be of arbitrary length. A value range fault
SOAP_TYPE(value
exceeds native representation) or
SOAP_LENGTH(value
exceeds range bounds) will be thrown by the deserializer if the value is out of range.
Other XSD integer types that are restrictions of
xsd:integer,
are
xsd:nonNegativeIntegerand
xsd:nonPositiveInteger,
which are further restricted by
xsd:positiveIntegerand
xsd:negativeInteger.
To bind these types to
__int128_twe
should also add the following definitions to
typemap.dat:
xsd__nonNegativeInteger = typedef xsd__integer xsd__nonNegativeInteger 0 : ; xsd__nonPositiveInteger = typedef xsd__integer xsd__nonPositiveInteger : 0 ; xsd__positiveInteger = typedef xsd__integer xsd__positiveInteger 1 : ; xsd__negativeInteger = typedef xsd__integer xsd__negativeInteger : -1 ;
NoteIf
__int128_t128
bit integers are not supported on your platform and if it is certain that
xsd:integervalues
are within 64 bit value bounds for your application's use, then you can map this type to
LONG64:
xsd__integer = typedef LONG64 xsd__integer;
Again, a value range fault
SOAP_TYPEor
SOAP_LENGTHwill
be thrown by the deserializer if the value is out of range.
See alsoSection numerical types.
xsd:decimal
The wsdl2h tool mapsxsd:decimalto
a string by default. To map
xsd:decimalto
extended precision floating point:
xsd__decimal = #import "custom/long_double.h" | long double
By contrast to all other custom serializers, this serializer enables
long doublenatively without requiring a new binding name (
xsd__decimalis
NOT defined).
If your system supports
<quadmath.h>quadruple
precision floating point
__float128,
you can map
xsd:decimalto
xsd__decimalthat
is an alias of
__float128:
xsd__decimal = #import "custom/float128.h"
WarningBeware that
xsd:decimalis
in principle a decimal value with arbitraty lengths. A value range fault
SOAP_TYPEwill
be thrown by the deserializer if the value is out of range.
In the XML payload the special values
INF,
-INF,
NaNrepresent
plus or minus infinity and not-a-number, respectively.
See alsoSection numerical types.
xsd:dateTime
The wsdl2h tool mapsxsd:dateTimeto
time_tby
default.
The trouble with
time_twhen represented
as 32 bit
longintegers is that it
is limited to dates between 1970 and 2038. A 64 bit
time_tis
safe to use if the target platform supports it, but lack of 64 bit
time_tportability
may still cause date range issues.
For this reason
struct tmshould
be used to represent wider date ranges. This custom serializer avoids using date and time information in
time_t.
You get the raw date and time information. You only lose the day of the week information. It is always Sunday (
tm_wday=0).
To map
xsd:dateTimeto
xsd__dateTimewhich
is an alias of
struct tm:
xsd__dateTime = #import "custom/struct_tm.h"
If the limited date range of
time_tis
not a problem but you want to increase the time precision with fractional seconds, then we suggest to map
xsd:dateTimeto
struct timeval:
xsd__dateTime = #import "custom/struct_timeval.h"
If the limited date range of
time_tis
not a problem but you want to use the C++11 time point type
std::chrono::system_clock::time_point(which
internally uses
time_t):
xsd__dateTime = #import "custom/chrono_time_point.h"
Again, we should make sure that the dates will not exceed the date range when using the default
time_tbinding
for
xsd:dateTimeor when binding
xsd:dateTimeto
struct timevalor to
std::chrono::system_clock::time_point.
These are safe to use in applications that use
xsd:dateTimeto
record date stamps within a given window. Otherwise, we recommend the
struct tmcustom serializer. You could even map
xsd:dateTimeto
a plain string (use
char*with C and
std::stringwith
C++). For example:
xsd__dateTime = | char*
See alsoSection date and time types.
xsd:date
The wsdl2h tool mapsxsd:dateto
a string by default. We can map
xsd:dateto
struct tm:
xsd__date = #import "custom/struct_tm_date.h"
The
xsd__datetype is an alias of
struct tm. The serializer ignores the time part and the deserializer only populates the date part of the struct, setting the time to 00:00:00. There is no unreasonable limit on the date range because the year field is stored as an integer (
int).
See alsoSection date and time types.
xsd:time
The wsdl2h tool mapsxsd:timeto
a string by default. We can map
xsd:timeto
an
unsigned long long(
ULONG64or
uint64_t)
integer with microsecond time precision:
xsd__time = #import "custom/long_time.h"
This type represents 00:00:00.000000 to 23:59:59.999999, from
0to
an upper bound of
86399999999. A microsecond
resolution means that a 1 second increment requires an increment of 1000000 in the integer value. The serializer adds a UTC time zone.
See alsoSection date and time types.
xsd:duration
The wsdl2h tool mapsxsd:durationto
a string by default, unless
xsd:durationis
mapped to a
long long(
LONG64or
int64_t)
type with with millisecond (ms) time duration precision:
xsd__duration = #import "custom/duration.h"
The
xsd__durationtype is a 64 bit
signed integer that can represent 106,751,991,167 days forwards (positive) and backwards (negative) in time in increments of 1 ms (1/1000 of a second).
Rescaling of the duration value by may be needed when adding the duration value to a
time_tvalue,
because
time_tmay or may not have
a seconds resolution, depending on the platform and possible changes to
time_t.
Rescaling is done automatically when you add a C++11
std::chrono::nanosecondsvalue
to a
std::chrono::system_clock::time_pointvalue.
To use
std::chrono::nanosecondsas
xsd:duration:
xsd__duration = #import "custom/chrono_duration.h"
This type can represent 384,307,168 days (2^63 nanoseconds) forwards and backwards in time in increments of 1 ns (1/1,000,000,000 of a second).
Certain observations with respect to receiving durations in years and months apply to both of these serializer decoders for
xsd:duration.
See alsoSection time duration types.
Class/struct member additions
All generated classes and structs can be augmented with additional members such as methods, constructors and destructors, and private members:prefix__type = $ member-declaration
For example, we can add method declarations and private members to a class, say
ns__recordas
follows:
ns__record = $ ns__record(const ns__record &); // copy constructor ns__record = $ void print(); // a print method ns__record = $ private: int status; // a private member
Note that method declarations cannot include any code, because soapcpp2's input permits only type declarations, not code.
Replacing XSD types by equivalent alternatives
Type replacements can be given to replace one type entirely with another given type:prefix__type1 == prefix__type2
This replaces all
prefix__type1by
prefix__type2in
the wsdl2h output.
WarningDo not agressively replace types, because this can cause XML validation to fail when a value-type mismatch is encountered in the XML input. Therefore, only replace similar types with other similar types that are wider (e.g.
shortby
intand
floatby
double).
The built-in typemap.dat variables $CONTAINER and $POINTER
Thetypemap.dat
$CONTAINERvariable
defines the container to emit in the generated declarations, which is
std::vectorby
default. For example, to emit
std::listas
the container in the wsdl2h-generated declarations:
$CONTAINER = std::list
The
typemap.dat
$POINTERvariable
defines the smart pointer to emit in the generated declarations, which replaces the use of
*pointers.
For example:
$POINTER = std::shared_ptr
Not all pointers in the generated output can be replaced by smart pointers. Regular pointers are still used as union members and for pointers to arrays of objects.
NoteThe standard smart pointer
std::shared_ptris
generally safe to use. Other smart pointers such as
std::unique_ptrand
std::auto_ptrmay
cause compile-time errors when classes have smart pointer members but no copy constructor (a default copy constructor). A copy constructor is required for non-shared smart pointer copying or swapping.
Alternatives to
std::shared_ptrof
the form
NAMESPACE::shared_ptrcan
be assigned to
$POINTERwhen the namespace
NAMESPACEalso
implements
NAMESPACE::make_sharedand
when the shared pointer class provides
reset()and
get()methods
and the dereference operator. For example Boost
boost::shared_ptr:
[ #include <boost/shared_ptr.hpp> ] $POINTER = boost::shared_ptr
The user-defined content between
[and
]ensures
that we include the Boost header files that are needed to support
boost::shared_ptrand
boost::make_shared.
User-defined content
Any other content to be generated by wsdl2h can be included intypemap.datby
enclosing it within brackets
[and
]anywhere
in the
typemap.datfile. Each of the
two brackets MUST appear at the start of a new line.
For example, we can add an
#import "wsa5.h"to
the wsdl2h-generated output as follows:
[ #import "import/wsa5.h" ]
which emits the
#import "import/wsa5.h"literally
at the start of the wsdl2h-generated header file.
Mapping C/C++ to XML schema
The soapcpp2 command generates the data binding implementation code from a data binding interfacefile.h:
soapcpp2 [options] file.h
where
file.his a gSOAP header file
that declares the XML data binding interface. The
file.his
typically generated by wsdl2h, but you can also declare one yourself. If so, add
//gsaopdirectives and
declare in this file all our C/C++ types you want to serialize in XML.
You can also declare functions that will be converted to Web service operations by soapcpp2. Global function declarations define service operations, which are of the form:
int prefix__func(arg1, arg2, ..., argn, result);
where
arg1,
arg2,
...,
argnare formal argument declarations
of the input and
resultis a formal
argument for the output, which must be a pointer or reference to the result object to be populated. More information can be found in the gSOAP
user guide.
Overview of serializable C/C++ types
The following C/C++ types are supported by soapcpp2 and mapped to XSD types and constructs. See the subsections below for more details or follow the links.List of Boolean types
| Boolean Type | Notes |
|---|---|
bool | C++ bool |
enum xsd__boolean | C alternative to C++ boolwith false_and true_ |
List of enumeration and bitmask types
| Enumeration Type | Notes |
|---|---|
enum | enumeration |
enum class | C++11 scoped enumeration (soapcpp2 -c++11) |
enum* | a bitmask that enumerates values 1, 2, 4, 8, ... |
enum* class | C++11 scoped enumeration bitmask (soapcpp2 -c++11) |
List of numerical types
| Numerical Type | Notes |
|---|---|
char | byte |
short | 16 bit integer |
int | 32 bit integer |
long | 32 bit integer |
LONG64 | 64 bit integer |
xsd__integer | 128 bit integer, use #import "custom/int128.h" |
long long | same as LONG64 |
unsigned char | unsigned byte |
unsigned short | unsigned 16 bit integer |
unsigned int | unsigned 32 bit integer |
unsigned long | unsigned 32 bit integer |
ULONG64 | unsigned 64 bit integer |
unsigned long long | same as ULONG64 |
int8_t | same as char |
int16_t | same as short |
int32_t | same as int |
int64_t | same as LONG64 |
uint8_t | same as unsigned char |
uint16_t | same as unsigned short |
uint32_t | same as unsigned int |
uint64_t | same as ULONG64 |
size_t | transient type (not serializable) |
float | 32 bit float |
double | 64 bit float |
long double | extended precision float, use #import "custom/long_double.h" |
xsd__decimal | <quadmath.h>128 bit quadruple precision float, use #import "custom/float128.h" |
typedef | declares a type name, with optional value range and string length bounds |
List of string types
| String Type | Notes |
|---|---|
char* | string (may contain UTF-8 with flag SOAP_C_UTFSTRING) |
wchar_t* | wide string |
std::string | C++ string (may contain UTF-8 with flag SOAP_C_UTFSTRING) |
std::wstring | C++ wide string |
char | fixed-size string, requires soapcpp2 option -b |
_QName | normalized QName content |
_XML | literal XML string content with wide characters in UTF-8 |
typedef | declares a new string type name, may restrict string length |
List of date and time types
| Date and Time Type | Notes |
|---|---|
time_t | date and time point since epoch |
struct tm | date and time point, use #import "custom/struct_tm.h" |
struct tm | date point, use #import "custom/struct_tm_date.h" |
struct timeval | date and time point, use #import "custom/struct_timeval.h" |
unsigned long long | time point in microseconds, use #import "custom/long_time.h" |
std::chrono::system_clock::time_point | date and time point, use #import "custom/chrono_time_point.h" |
List of time duration types
| Time Duration Type | Notes |
|---|---|
long long | duration in milliseconds, use #import "custom/duration.h" |
std::chrono::nanoseconds | duration in nanoseconds, use #import "custom/chrono_duration.h" |
List of classes and structs
| Classes, Structs, and Members | Notes |
|---|---|
class | C++ class with single inheritance only |
struct | C struct or C++ struct without inheritance |
std::shared_ptr<T> | C++11 smart shared pointer |
std::unique_ptr<T> | C++11 smart pointer |
std::auto_ptr<T> | C++ smart pointer |
std::deque<T> | use #import "import/stldeque.h" |
std::list<T> | use #import "import/stllist.h" |
std::vector<T> | use #import "import/stlvector.h" |
std::set<T> | use #import "import/stlset.h" |
template<T> class | a container with begin(), end(), size(), clear(), and insert()methods |
T* | data member: pointer to data of type Tor points to array of Tof size __size |
T | data member: fixed-size array of type T |
union | data member: requires a variant selector member __union |
void* | data member: requires a __typemember to indicate the type of object pointed to |
List of special classes and structs
| Special Classes and Structs | Notes |
|---|---|
| Special Array class/struct | single and multidimensional SOAP Arrays |
| Special Wrapper class/struct | complexTypes with simpleContent, wraps __itemmember |
xsd__hexBinary | binary content |
xsd__base64Binary | binary content and optional MIME/MTOM attachments |
xsd__anyType | DOM elements, use #import "dom.h" |
@xsd__anyAttribute | DOM attributes, use #import "dom.h" |
Colon notation versus name prefixing with XML tag name translation
To bind C/C++ type names to XSD types, a simple form of name prefixing is used by the gSOAP tools by prepending the XML namespace prefix to the C/C++ type name with a pair of undescrores. This also ensures that name clashes cannot occur when multiple WSDLand XSD files are converted to C/C++. Also, C++ namespaces are not sufficiently rich to capture XML schema namespaces accurately, for example when class members are associated with schema elements defined in another XML namespace and thus the XML namespace
scope of the member's name is relevant, not just its type.
However, from a C/C++ centric point of view this can be cumbersome. Therefore, colon notation is an alternative to physically augmenting C/C++ names with prefixes.
For example, the following class uses colon notation to bind the
recordclass
to the
urn:typesschema:
//gsoap ns schema namespace: urn:types
class
ns:record // binding 'ns:' to a type name
{
public:
std::string name;
uint64_t SSN;
ns:record *spouse;
// using 'ns:' with the type name
ns:record();
// using 'ns:' here too
~ns:record();
// and here
};
The colon notation is stripped away by soapcpp2 when generating the data binding implementation code for our project. So the final code just uses
recordto
identify this class and its constructor/destructor.
When using colon notation make sure to be consistent and not use colon notation mixed with prefixed forms. The name
ns:recorddiffers
from
ns__record, because
ns:recordis
compiled to an unqualified
recordname.
Colon notation also facilitates overruling the elementFormDefault and attributeFormDefault declaration that is applied to local elements and attributes, when declared as members of classes, structs, and unions. For more details, see qualified
and unqualified members.
A C/C++ identifier name (a type name, member name, function name, or parameter name) is translated to an XML tag name by the following rules:
Two leading underscores indicates that the identifier name has no XML tag name, i.e. this name is not visible in XML and is not translated.
A leading underscore is removed, but the underscore indicates that: a) a struct/class member name or parameter name has a wildcard XML tag name (i.e. matches any XML tag), or b) a type name that has a document
root element definition.
Trailing underscores are removed (i.e. trailing underscores can be used to avoid name clashes with keywords).
Underscores within names are translated to hyphens (hyphens are more common in XML tags).
_USCOREis translated to an underscore
in the translated XML tag name.
_DOTis translated to a dot (
.)
in the translated XML tag name.
_xHHHHis translated to the Unicode
character with code point HHHH.
C++11 Unicode identifier name characters in UTF-8 are translated as-is.
For example, the C/C++ namespace qualified identifier name
s_a__my_wayis
translated to the XML tag name
s-a:my-wayby
translating the prefix
s_aand the
local name
my_way.
Struct/class member and parameter name translation can be overruled by using backtick XML tags (with gSOAP 2.8.30
or higher).
C++ Bool and C alternatives
The C++booltype is bound to built-in
XSD type
xsd:boolean.
The C alternative is to define an enumeration:
enum xsd__boolean { false_, true_ };
or by defining an enumeration in C with pseudo-scoped enumeration constants:
enum xsd__boolean { xsd__boolean__false, xsd__boolean__true };
The XML value space of these types is
falseand
true,
but also accepted are
0and
1values
for false and true, respectively.
To prevent name clashes,
false_and
true_have
an underscore. Trailing underscores are removed from the XML value space.
Enumerations and bitmasks
Enumerations are mapped to XSD simpleType enumeration restrictions ofxsd:string,
xsd:QName,
and
xsd:long.
Consider for example:
enum ns__Color { RED, WHITE, BLUE };
which maps to a simpleType restriction of
xsd:stringin
the soapcpp2-generated schema:
<simpleType name="Color"> <restriction base="xsd:string"> <enumeration value="RED"/> <enumeration value="WHITE"/> <enumeration value="BLUE"/> </restriction> </simpleType>
Enumeration name constants can be pseudo-scoped to prevent name clashes, because enumeration name constants have a global scope in C and C++:
enum ns__Color { ns__Color__RED, ns__Color__WHITE, ns__Color__BLUE };
You can also use C++11 scoped enumerations to prevent name clashes:
enum class ns__Color : int { RED, WHITE, BLUE };
Here, the enumeration class base type
: intis optional. In place of
intin
the example above, we can also use
int8_t,
int16_t,
int32_t,
or
int64_t.
The XML value space of the enumertions defined above is
RED,
WHITE,
and
BLUE.
Prefix-qualified enumeration name constants are mapped to simpleType restrictions of
xsd:QName,
for example:
enum ns__types { xsd__int, xsd__float };
which maps to a simpleType restriction of
xsd:QNamein
the soapcpp2-generated schema:
<simpleType name="types"> <restriction base="xsd:QName"> <enumeration value="xsd:int"/> <enumeration value="xsd:float"/> </restriction> </simpleType>
Enumeration name constants can be pseudo-numeric as follows:
enum ns__Primes { _3 = 3, _5 = 5, _7 = 7, _11 = 11 };
which maps to a simpleType restriction of
xsd:long:
<simpleType name="Color"> <restriction base="xsd:long"> <enumeration value="3"/> <enumeration value="5"/> <enumeration value="7"/> <enumeration value="11"/> </restriction> </simpleType>
The XML value space of this type is
3,
5,
7,
and
11.
Besides (pseudo-) scoped enumerations, another way to prevent name clashes accross enumerations is to start an enumeration name constant with one underscore or followed it by any number of underscores, which makes it unique. The leading and trailing underscores
are removed from the XML value space.
enum ns__ABC { A, B, C };
enum ns__BA { B, A };
// BAD: B = 1 but B is already defined as 2
enum ns__BA_ { B_, A_ };
// OK
The gSOAP soapcpp2 tool permits reusing enumeration name constants across (non-scoped) enumerations as long as these values are assigned the same constant. Therefore, the following is permitted:
enum ns__Primes { _3 = 3, _5 = 5, _7 = 7, _11 = 11 };
enum ns__Throws { _1 = 1, _2 = 2, _3 = 3, _4 = 4, _5 = 5, _6 = 6 };
A bitmask type is an
enum*"product"
enumeration with a geometric, power-of-two sequence of values assigned to the enumeration constants:
enum* ns__Options { SSL3, TLS10, TLS11, TLS12 };
where the product enum assigns 1 to
SSL3,
2 to
TLS10, 4 to
TLS11,
and 8 to
TLS12, which allows these
enumeration constants to be used in composing bitmasks with
|(bitwise
or)
&(bitwise and), and
~(bitwise
not):
enum ns__Options options = (enum ns__Options)(SSL3 | TLS10 | TLS11 | TLS12);
if (options & SSL3)
// if SSL3 is an option, warn and remove from options
{
warning();
options &= ~SSL3;
}
The bitmask type maps to a simpleType list restriction of
xsd:stringin
the soapcpp2-generated schema:
<simpleType name="Options"> <list> <restriction base="xsd:string"> <enumeration value="SSL3"/> <enumeration value="TLS10"/> <enumeration value="TLS11"/> <enumeration value="TLS12"/> </restriction> </list> </simpleType>
The XML value space of this type consists of all 16 possible subsets of the four values, represented by an XML string with space-separated values. For example, the bitmask
TLS10 | TLS11 | TLS12equals 14 and is represented by the XML string
TLS10 TLS11 TLS12.
You can also use C++11 scoped enumerations with bitmasks:
enum*
class ns__Options { SSL3, TLS10, TLS11, TLS12 };
The base type of a scoped enumeration bitmask, when explicitly given, is ignored. The base type is either
intor
int64_t,
depending on the number of constants enumerated in the bitmask.
To convert
enumname constants and
bitmasks to a string, we use the auto-generated function for enum
T:
const
char *soap_T2s(struct soap*,
enum T val)
The string returned is stored in an internal buffer of the current
soapcontext,
so you MUST copy it to keep it from being overwritten. For example, use
char*soap_strdup(struct soap*, const char*).
To convert a string to an
enumconstant
or bitmask, we use the auto-generated function
int soap_s2T(struct soap*,
const
char *str, enum T *val)
This function takes the name (or names, space-separated for bitmasks) of the enumeration constant in a string
str.
Names should be given without the pseudo-scope prefix and without trailing underscores. The function sets
valto
the corresponding integer enum constant or to a bitmask. The function returns
SOAP_OK(zero)
on success or an error if the string is not a valid enumeration name.
Numerical types
Integer and floating point types are mapped to the equivalent built-in XSD types with the same sign and bit width.The
size_ttype is transient (not
serializable) because its width is platform dependent. We recommend to use
uint64_tinstead.
The XML value space of integer types are their decimal representations without loss of precision.
The XML value space of floating point types are their decimal representations. The decimal representations are formatted with the printf format string "%.9G" for floats and the printf format string "%.17lG" for double. To change the format strings, we can
assign new strings to the following
struct soapcontext members:
soap.float_format =
"%g";
soap.double_format =
"%lg";
soap.long_double_format =
"%Lg";
Note that decimal representations may result in a loss of precision of the least significant decimal. Therefore, the format strings that are used by default are sufficiently precise to avoid loss, but this may result in long decimal fractions in the XML
value space.
The
long doubleextended floating
point type requires a custom serializer:
#import "custom/long_double.h"
... use
long double ...
You can now use
long double, which
has a serializer that serializes this type as
xsd:decimal.
Compile and link your code with
custom/long_double.c.
The value space of floating point values includes the special values
INF,
-INF,
and
NaN. You can check a value for
plus or minus infinity and not-a-number as follows:
soap_isinf(x) && x > 0
// is x INF?
soap_isinf(x) && x < 0
// is x -INF?
soap_isnan(x)
// is x NaN?
To assign these values, use:
// x is float // x is double, long double, or __float128
x = FLT_PINFY; x = DBL_PINFTY;
x = FLT_NINFY; x = DBL_NINFTY;
x = FLT_NAN; x = DBL_NAN;
If your system supports
__float128then
you can also use this 128 bit floating point type with a custom serializer:
#import "custom/float128.h"
... use xsd__decimal ...
Then use the
xsd__decimalalias of
__float128,
which has a serializer. Do not use
__float128directly,
which is transient (not serializable).
To check for
INF,
-INF,
and
NaNof a
__float128value
use:
isinfq(x) && x > 0
// is x INF?
isinfq(x) && x < 0
// is x -INF?
isnanq(x)
// is x NaN?
The range of a typedef-defined numerical type can be restricted using the range
:operator
with inclusive lower and upper bounds. For example:
typedef
int ns__narrow -10 : 10;
This maps to a simpleType restriction of
xsd:intin
the soapcpp2-generated schema:
<simpleType name="narrow"> <restriction base="xsd:int"> <minInclusive value="-10"/> <maxInclusive value="10"/> </restriction> </simpleType>
The lower and upper bound of a range are optional. When omitted, values are not bound from below or from above, respectively.
The range of a floating point typedef-defined type can be restricted within floating point constant bounds.
Also with a floating point typedef a printf format pattern can be given of the form
"%[width][.precision]f"to
format decimal values using the given width and precision fields:
typedef
float ns__PH
"%5.2f" 0.0 : 14.0;
This maps to a simpleType restriction of
xsd:floatin
the soapcpp2-generated schema:
<simpleType name="PH"> <restriction base="xsd:float"> <totalDigits value="5"/> <fractionDigits value="2"/> <minInclusive value="0"/> <maxInclusive value="14"/> </restriction> </simpleType>
For exclusive bounds, we use the
<operator
instead of the
:range operator:
typedef
float ns__epsilon 0.0 < 1.0;
Values
epsof
ns__epsilonare
restricted between
0.0 < eps < 1.0.
This maps to a simpleType restriction of
xsd:floatin
the soapcpp2-generated schema:
<simpleType name="epsilon"> <restriction base="xsd:float"> <minExclusive value="0"/> <maxExclusive value="1"/> </restriction> </simpleType>
To make just one of the bounds exclusive, while keeping the other bound inclusive, we add a
<on
the left or on the right side of the range ':' operator. For example:
typedef
float ns__pos 0.0 < : ;
// 0.0 < pos
typedef
float ns__neg : < 0.0 ;
// neg < 0.0
It is valid to make both left and right side exclusive with
< : <which is in fact identical to the exlusive range
<operator:
typedef
float ns__epsilon 0.0 < : < 1.0;
// 0.0 < eps < 1.0
It helps to think of the
:as a placeholder
of the value between the two bounds, which is easier to memorize than the shorthand forms of bounds from which the
:is
removed:
| Bounds | Validation Check | Shorthand |
|---|---|---|
| 1 : | 1 <= x | 1 |
| 1 : 10 | 1 <= x <= 10 | |
| : 10 | x <= 10 | |
| 1 < : < 10 | 1 < x < 10 | 1 < 10 |
| 1 : < 10 | 1 <= x < 10 | |
| : < 10 | x < 10 | < 10 |
| 1 < : | 1 < x | 1 < |
| 1 < : 10 | 1 < x <= 10 |
float, also
doubleand
long doublevalues can be restricted. For example, consider a nonzero probability extended floating point precision type:
#import "custom/long_double.h"
typedef
long double ns__probability
"%16Lg" 0.0 < : 1.0;
Value range restrictions are validated by the parser for all inbound XML data. A type fault
SOAP_TYPEwill
be thrown by the deserializer if the value is out of range.
Finally, if your system supports
__int128_tthen
you can also use this 128 bit integer type with a custom serializer:
#import "custom/int128.h"
... use xsd__integer ...
Use the
xsd__integeralias of
__int128_t,
which has a serializer. Do not use
__int128_tdirectly,
which is transient (not serializable).
To convert numeric values to a string, we use the auto-generated function for numeric type
T:
const
char *soap_T2s(struct soap*, T val)
For numeric types
T, the string returned
is stored in an internal buffer of the current
soapcontext,
so you MUST copy it to keep it from being overwritten. For example, use
char*soap_strdup(struct soap*, const char*).
To convert a string to a numeric value, we use the auto-generated function
int soap_s2T(struct soap*,
const
char *str, T *val)
where
Tis for example
int,
LONG64,
float,
decimal(the
custom serializer name of
long double)
or
xsd__integer(the custom serializer
name of
__int128_t). The function
soap_s2Treturns
SOAP_OKon
success or an error when the value is not numeric. For floating point types, "INF", "-INF" and "NaN" are valid strings to convert to numbers.
String types
String types are mapped to the built-inxsd:stringand
xsd:QNameXSD
types.
The wide strings
wchar_t*and
std::wstringmay
contain Unicode that is preserved in the XML value space.
Strings
char*and
std::stringcan
only contain extended Latin, but we can store UTF-8 content that is preserved in the XML value space when the
struct soapcontext is initialized with the flag
XML_C_UTFSTRING.
WarningBeware that many XML 1.0 parsers reject all control characters (those between
#x1and
#x1F)
except for
#x9,
#xA,
and
#xD. With the newer XML 1.1 version
parsers (including gSOAP) you should be fine.
The length of a string of a typedef-defined string type can be restricted:
typedef std::string ns__password 6 : 16;
which maps to a simpleType restriction of
xsd:stringin
the soapcpp2-generated schema:
<simpleType name="password"> <restriction base="xsd:string"> <minLength value="6"/> <maxLength value="16"/> </restriction> </simpleType>
String length restrictions are validated by the parser for inbound XML data. A value length fault
SOAP_LENGTHwill
be thrown by the deserializer if the string is too long or too short.
In addition, an XSD regex pattern restriction can be associated with a string typedef:
typedef std::string ns__password
"([a-zA-Z]|[0-9]|-)+" 6 : 16;
which maps to a simpleType restriction of
xsd:stringin
the soapcpp2-generated schema:
<simpleType name="password"> <restriction base="xsd:string"> <pattern value="([a-zA-Z0-9]|-)+"/> <minLength value="6"/> <maxLength value="16"/> </restriction> </simpleType>
Pattern restrictions are validated by the parser for inbound XML data only if the
soap::fsvalidateand
soap::fwvalidatecallbacks
are defined, see the gSOAP user guide.
Exclusive length bounds can be used with strings:
typedef std::string ns__string255 : < 256;
// same as 0 : 255
Fixed-size strings (
char) are
rare occurrences in the wild, but apparently still used in some projects to store strings. To facilitate fixed-size string serialization, use soapcpp2 option
-b.
For example:
typedef
char ns__buffer[10];
// requires soapcpp2 option -b
which maps to a simpleType restriction of
xsd:stringin
the soapcpp2-generated schema:
<simpleType name="buffer"> <restriction base="xsd:string"> <maxLength value="9"/> </restriction> </simpleType>
Note that fixed-size strings MUST contain NUL-terminated text and SHOULD NOT contain raw binary data. Also, the length limitation is more restrictive for UTF-8 content (enabled with the
SOAP_C_UTFSTRING)
that requires multibyte character encodings. As a consequence, UTF-8 content may be truncated to fit.
Note that raw binary data can be stored in a
xsd__base64Binaryor
xsd__hexBinarystructure,
or transmitted as a MIME attachment.
The built-in
_QNametype is a regular
C string type (
char*) that maps to
xsd:QNamebut
has the added advantage that it holds normalized qualified names. There are actually two forms of normalized QName content, to ensure any QName is represented accurately and uniquely:
"prefix:name"
"\"URI\":name"
The first form of string is used when the prefix (and the binding URI) is defined in the namespace table and is bound to a URI (see the .nsmap file). The second form is used when the URI is not defined in the namespace table and therefore no prefix is available
to bind and normalize the URI to.
A
_QNamestring may contain a sequence
of space-separated QName values, not just one, and all QName values are normalized to the format shown above.
To define a
std::stringbase type
for
xsd:QName, we use a typedef:
typedef std::string xsd__QName;
The
xsd__QNamestring content is
normalized, just as with the
_QNamenormalization.
To serialize strings that contain literal XML content to be reproduced in the XML value space, use the built-in
_XMLstring
type, which is a regular C string type (
char*)
that maps to plain XML CDATA.
To define a
std::stringbase type
for literal XML content, use a typedef:
typedef std::string XML;
Strings can hold any of the values of the XSD built-in primitive types. We can use a string typedef to declare the use of the string type as a XSD built-in type:
typedef std::string xsd__token;
You MUST ensure that the string values we populate in this type conform to the XML standard, which in case of
xsd:tokenis
the lexical and value spaces of
xsd:tokenare
the sets of all strings after whitespace replacement of any occurrence of
#x9,
#xA,
and
#xDby
#x20and
collapsing.
To copy
char*or
wchar_t*strings
with a context that manages the allocated memory, use functions
char *soap_strdup(struct soap*,
const char*)
wchar_t *soap_wstrdup(struct soap*, const
wchar_t*)
To convert a wide string to a UTF-8 encoded string, use function
const char* SOAP_FMAC2 soap_wchar2s(struct soap*,
const
wchar_t *s)
The function allocates and returns a string, with its memory being managed by the context.
To convert a UTF-8 encoded string to a wide string, use function
int soap_s2wchar(struct soap*,
const
char *from, wchar_t **to,
long minlen,
long maxlen)
where
tois set to point to an allocated
wchar_t*string.
Pass
-1for
minlenand
maxlento
ignore length constraints on the target string. The function returns
SOAP_OKor
an error when the length constraints are not met.
Date and time types
The C/C++time_ttype is mapped to
the built-in
xsd:dateTimeXSD type
that represents a date and time within a time zone (typically UTC).
The XML value space contains ISO 8601 Gregorian time instances of the form
[-]CCYY-MM-DDThh:mm:ss.sss[Z|(+|-)hh:mm],
where
Zis the UTC time zone or a time
zone offset
(+|-)hh:mm]from UTC is
used.
A
time_tvalue is considered and
represented in UTC by the serializer.
Because the
time_tvalue range is
restricted to dates after 01/01/1970 and before 2038 assuming
time_tis
a
long32 bit, care must be taken to
ensure the range of
xsd:dateTimevalues
in XML exchanges do not exceed the
time_trange.
This restriction does not hold for
struct tm(
<time.h>), which we can
use to store and exchange a date and time in UTC without date range restrictions. The serializer uses the
struct tmmembers directly for the XML value space of
xsd:dateTime:
struct tm
{
int tm_sec;
// seconds (0 - 60)
int tm_min;
// minutes (0 - 59)
int tm_hour;
// hours (0 - 23)
int tm_mday;
// day of month (1 - 31)
int tm_mon;
// month of year (0 - 11)
int tm_year;
// year - 1900
int tm_wday;
// day of week (Sunday = 0) (NOT USED)
int tm_yday;
// day of year (0 - 365) (NOT USED)
int tm_isdst;
// is summer time in effect?
char* tm_zone;
// abbreviation of timezone (NOT USED)
};
You will lose the day of the week information. It is always Sunday (
tm_wday=0)
and the day of the year is not set either. The time zone is UTC.
This
struct tmtype is mapped to
the built-in
xsd:dateTimeXSD type
and serialized with the custom serializer
custom/struct_tm.hthat
declares a
xsd__dateTimetype:
#import "custom/struct_tm.h"
// import typedef struct tm xsd__dateTime;
... use xsd__dateTime ...
Compile and link your code with
custom/struct_tm.c.
The
struct timeval(
<sys/time.h>)
type is mapped to the built-in
xsd:dateTimeXSD
type and serialized with the custom serializer
custom/struct_timeval.hthat
declares a
xsd__dateTimetype:
#import "custom/struct_timeval.h"
// import typedef struct timeval xsd__dateTime;
... use xsd__dateTime ...
Compile and link your code with
custom/struct_timeval.c.
Note that the same value range restrictions apply to
struct timevalas they apply to
time_t.
The added benefit of
struct timevalis
the addition of a microsecond-precise clock:
struct timeval
{
time_t tv_sec;
// seconds since Jan. 1, 1970
suseconds_t tv_usec;
// and microseconds
};
A C++11
std::chrono::system_clock::time_pointtype
is mapped to the built-in
xsd:dateTimeXSD
type and serialized with the custom serializer
custom/chrono_time_point.hthat
declares a
xsd__dateTimetype:
#import "custom/chrono_time_point.h"
// import typedef std::chrono::system_clock::time_point xsd__dateTime;
... use xsd__dateTime ...
Compile and link your code with
custom/chrono_time_point.cpp.
The
struct tmtype is mapped to the
built-in
xsd:dateXSD type and serialized
with the custom serializer
custom/struct_tm_date.hthat
declares a
xsd__datetype:
#import "custom/struct_tm_date.h"
// import typedef struct tm xsd__date;
... use xsd__date ...
Compile and link your code with
custom/struct_tm_date.c.
The XML value space of
xsd:dateare
Gregorian calendar dates of the form
[-]CCYY-MM-DD[Z|(+|-)hh:mm]with
a time zone.
The serializer ignores the time part and the deserializer only populates the date part of the struct, setting the time to 00:00:00. There is no unreasonable limit on the date range because the year field is stored as an integer (
int).
An
unsigned long long(
ULONG64or
uint64_t)
type that contains a 24 hour time in microseconds UTC is mapped to the built-in
xsd:timeXSD
type and serialized with the custom serializer
custom/long_time.hthat
declares a
xsd__timetype:
#import "custom/long_time.h"
// import typedef unsigned long long xsd__time;
... use xsd__time ...
Compile and link your code with
custom/long_time.c.
This type represents
00:00:00.000000to
23:59:59.999999,
from 0 to an upper bound of 86,399,999,999. A microsecond resolution means that a 1 second increment requires an increment of 1,000,000 in the integer value.
The XML value space of
xsd:timeare
points in time recurring each day of the form
hh:mm:ss.sss[Z|(+|-)hh:mm],
where
Zis the UTC time zone or a time
zone offset from UTC is used. The
xsd__timevalue
is always considered and represented in UTC by the serializer.
To convert date and/or time values to a string, we use the auto-generated function for type
T:
const
char *soap_T2s(struct soap*, T val)
For date and time types
T, the string
returned is stored in an internal buffer of the current
soapcontext,
so you MUST copy it to keep it from being overwritten. For example, use
char*soap_strdup(struct soap*, const char*).
To convert a string to a date/time value, we use the auto-generated function
int soap_s2T(struct soap*,
const
char *str, T *val)
where
Tis for example
dateTime(for
time_t),
xsd__dateTime(for
struct tm,
struct timeval, or
std::chrono::system_clock::time_point).
The function
soap_s2Treturns
SOAP_OKon
success or an error when the value is not a date/time.
Time duration types
The XML value space ofxsd:durationare
values of the form
PnYnMnDTnHnMnSwhere
the capital letters are delimiters. Delimiters may be omitted when the corresponding member is not used.
A
long long(
LONG64or
int64_t)
type that contains a duration (time lapse) in milliseconds is mapped to the built-in
xsd:durationXSD
type and serialized with the custom serializer
custom/duration.hthat
declares a
xsd__durationtype:
#import "custom/duration.h"
// import typedef long long xsd__duration;
... use xsd__duration ...
Compile and link your code with
custom/duration.c.
The duration type
xsd__durationcan
represent 106,751,991,167 days forward and backward with millisecond precision.
Durations that exceed a month are always output in days, rather than months to avoid days-per-month conversion inacurracies.
Durations that are received in years and months instead of total number of days from a reference point are not well defined, since there is no accepted reference time point (it may or may not be the current time). The decoder simple assumes that there are
30 days per month. For example, conversion of "P4M" gives 120 days. Therefore, the durations "P4M" and "P120D" are assumed to be identical, which is not necessarily true depending on the reference point in time.
Rescaling of the duration value by may be needed when adding the duration value to a
time_tvalue,
because
time_tmay or may not have
a seconds resolution, depending on the platform and possible changes to
time_t.
Rescaling is done automatically when you add a C++11
std::chrono::nanosecondsvalue
to a
std::chrono::system_clock::time_pointvalue.
To use
std::chrono::nanosecondsas
xsd:duration:
#import "custom/chrono_duration.h"
// import typedef std::chrono::duration xsd__duration;
... use xsd__duration ...
Compile and link your code with
custom/chrono_duration.cpp.
This type can represent 384,307,168 days (2^63 nanoseconds) forwards and backwards in time in increments of 1 ns (1/1000000000 second).
The same observations with respect to receiving durations in years and months apply to this serializer's decoder.
To convert duration values to a string, we use the auto-generated function
const
char *soap_xsd__duration2s(struct soap*, xsd__duration val)
The string returned is stored in an internal buffer, so you MUST copy it to keep it from being overwritten, Use
soap_strdup(struct soap*, const char*)for example to copy this string.
To convert a string to a duration value, we use the auto-generated function
int soap_s2xsd__dateTime(struct soap*,
const
char *str, xsd__dateTime *val)
The function returns
SOAP_OKon success
or an error when the value is not a duration.
Classes and structs
Classes and structs are mapped to XSD complexTypes. The XML value space consists of XML elements with attributes and subelements, possibly constrained by validation rules that enforce element and attribute occurrence contraints, numerical value range constraints,and string length and pattern constraints.
Classes that are declared with the gSOAP tools are limited to single inheritence only. Structs cannot be inherited.
The class and struct name is bound to an XML namespace by means of the prefix naming convention or by using colon
notation:
//gsoap ns schema namespace: urn:types
class
ns__record
{
public:
std::string name;
uint64_t SSN;
ns__record *spouse;
ns__record();
~ns__record();
protected:
struct soap *soap;
};
In the example above, we also added a context pointer to the
struct soapthat manages this instance. It is set when the instance is created in the engine's context, for example when deserialized and populated by the engine.
The class maps to a complexType in the soapcpp2-generated schema:
<complexType name="record"> <sequence> <element name="name" type="xsd:string" minOccurs="1" maxOccurs="1"/> <element name="SSN" type="xsd:unsignedLong" minOccurs="1" maxOccurs="1"/> <element name="spouse" type="ns:record" minOccurs="0" maxOccurs="1" nillable="true"/> </sequence> </complexType>
Serializable versus transient types and members
Public data members of a class or struct are serialized. Private and protected members are transient and not serializable.Also
constand
staticmembers
are not serializable, with the exception of
const char*and
const wchar_t*. Types
and specific class/struct members can also be made transient with the
externqualifier:
extern
class std::ostream;
// declare 'std::ostream' transient
class
ns__record
{
public:
extern
int num;
// not serialized
std::ostream out;
// not serialized
static
const
int MAX = 1024; // not serialized
};
By declaring
std::ostreamtransient
with
externyou can use this type wherever
you need it without soapcpp2 complaining that this class is not defined.
Volatile classes and structs
Classes and structs can be declaredvolatilewith
the gSOAP tools. This means that they are already declared elsewhere in your project's source code and you do not want soapcpp2 to generate code with a second declaration of these types.
For example,
struct tmis declared
in
<time.h>. You can make it serializable
and include a partial list of data members that you want to serialize:
volatile
struct tm
{
int tm_sec;
// seconds (0 - 60)
int tm_min;
// minutes (0 - 59)
int tm_hour;
// hours (0 - 23)
int tm_mday;
// day of month (1 - 31)
int tm_mon;
// month of year (0 - 11)
int tm_year;
// year - 1900
};
You can declare classes and structs
volatilefor
any such types you want to serialize by only providing the public data members you want to serialize.
In addition, colon notation is a simple and effective way to bind an existing class or struct to a schema. For
example, you can change the
tmname
as follows without affecting the code that uses
struct tmgenerated by soapcpp2:
volatile
struct ns:tm { ... }
This struct maps to a complexType in the soapcpp2-generated schema:
<complexType name="tm"> <sequence> <element name="tm-sec" type="xsd:int" minOccurs="1" maxOccurs="1"/> <element name="tm-min" type="xsd:int" minOccurs="1" maxOccurs="1"/> <element name="tm-hour" type="xsd:int" minOccurs="1" maxOccurs="1"/> <element name="tm-mday" type="xsd:int" minOccurs="1" maxOccurs="1"/> <element name="tm-mon" type="xsd:int" minOccurs="1" maxOccurs="1"/> <element name="tm-year" type="xsd:int" minOccurs="1" maxOccurs="1"/> </sequence> </complexType>
Mutable classes and structs
Classes and structs can be declaredmutablewith
the gSOAP tools. This means that their definition can be spread out over the source code. This promotes the concept of a class or struct as a row of named values, also known as a named tuple, that can be extended at compile time in your source
code with additional members. Because these types differ from the traditional object-oriented principles and design concepts of classes and objects, constructors and destructors cannot be defined (also because we cannot guarantee merging these into one such
that all members will be initialized). A default constructor, copy constructor, assignment operation, and destructor will be assigned automatically by soapcpp2.
mutable
struct ns__tuple
{
@std::string id;
};
mutable
struct ns__tuple
{
std::string name;
std::string value;
};
The members are collected into one definition generated by soapcpp2. Members may be repeated from one definition to another, but only if their associated types are identical. So, for example, a third extension with a
valuemember
with a different type fails:
mutable
struct ns__tuple
{
float value;
// BAD: value is already declared std::string
};
The
mutableconcept has proven to
be very useful when declaring and collecting SOAP Headers for multiple services, which are collected into one
struct SOAP_ENV__Headerby
the soapcpp2 tool.
Default member values in C and C++
Class and struct data members in C and C++ may be declared with an optional default initialization value that is provided "inline" with the declaration of the member:class
ns__record
{
public:
std::string name =
"Joe";
...
};
Alternatively, use C++11 default initialization syntax:
class
ns__record
{
public:
std::string name {
"Joe" };
...
};
These initializations are made by the default constructor that is added by soapcpp2 to each class and struct (in C++ only). A constructor is only added when a default constructor is not already defined with the class declaration.
You can explicitly (re)initialize an object with these initial values by using the soapcpp2 auto-generated functions:
void T::soap_default(struct soap*)for
class T(C++ only)
void soap_default_T(struct soap*, T*)for
struct T(C and C++).
Initializations can only be provided for members that have primitive types (
bool,
enum,
time_t,
numeric and string types).
See alsoSection operations on classes and structs.
Attribute members and backtick XML tags
Class and struct data members are declared as XML attributes by annotating their type with a@qualifier:
class
ns__record
{
public:
@std::string name;
@uint64_t SSN;
ns__record *spouse;
};
This class maps to a complexType in the soapcpp2-generated schema:
<complexType name="record"> <sequence> <element name="spouse" type="ns:record" minOccurs="0" maxOccurs="1" nillable="true"/> </sequence> <attribute name="name" type="xsd:string" use="required"/> <attribute name="SSN" type="xsd:unsignedLong" use="required"/> </complexType>
An example XML instance of
ns__recordis:
<ns:record xmlns:ns="urn:types" name="Joe" SSN="1234567890"> <spouse name="Jane" SSN="1987654320"> </spouse> </ns:record>
Attribute data members are restricted to primitive types (
bool,
enum,
time_t,
numeric and string types),
xsd__hexBinary,
xsd__base64Binary,
and custom serializers, such as
xsd__dateTime.
Custom serializers for types that may be used as attributes MUST define
soap_s2Tand
soap_T2sfunctions
that convert values of type
Tto strings
and back.
Attribute data members can be pointers and smart pointers to these types, which permits attributes to be optional.
The XML tag name of a class/struct member is the name of the member with the usual XML tag translation, see colon
notation.
To override the standard translation of identifier names to XML tag names of attributes and elements, add the XML tag name in backticks (requires gSOAP 2.8.30 or higher):
class
ns__record
{
public:
@std::string name `full-name`;
@uint64_t SSN `tax-id`;
ns__record *spouse `married-to`;
};
This class maps to a complexType in the soapcpp2-generated schema:
<complexType name="record"> <sequence> <element name="married-to" type="ns:record" minOccurs="0" maxOccurs="1" nillable="true"/> </sequence> <attribute name="full-name" type="xsd:string" use="required"/> <attribute name="tax-id" type="xsd:unsignedLong" use="required"/> </complexType>
An example XML instance of
ns__recordis:
<ns:record xmlns:ns="urn:types" full-name="Joe" tax-id="1234567890"> <married-to full-name="Jane" tax-id="1987654320"> </married-to> </ns:record>
A backtick XML tag name may contain any non-empty sequence of ASCII and UTF-8 characters except white space and the backtick character. A backtick tag can be combined with member constraints and default member initializers:
@uint64_t SSN `tax-id` 0:1 = 999;
Qualified and unqualified members
Class, struct, and union data members are mapped to namespace qualified or unqualified tag names of local elements and attributes. If a data member has no prefix then the default form of qualification is applied based on the element/attribute form that isdeclared with the schema of the class, struct, or union type. If the member name has a namespace prefix by colon notation, then the prefix overrules the default (un)qualified form. Therefore, colon
notation is an effective mechanism to control qualification of tag names of individual members of classes, structs, and unions.
The XML schema elementFormDefault and attributeFormDefault declarations control the tag name qualification of local elements and attributes, respectively.
"unqualified" indicates that local elements/attributes are not qualified with the namespace prefix.
"qualified" indicates that local elements/attributes must be qualified with the namespace prefix.
Individual schema declarations of local elements and attributes may overrule this by using the form declaration in a schema and by using colon notation to add namespace prefixes to class, struct, and union members in the header file for soapcpp2.
Consider for example an
ns__recordclass
in the
nsnamespace in which local
elements are qualified and local attributes are unqualified by default:
//gsoap ns schema namespace: urn:types
//gsoap ns schema elementForm: qualified
//gsoap ns schema attributeForm: unqualified
class
ns__record
{
public:
@std::string name;
@uint64_t SSN;
ns__record *spouse;
};
This class maps to a complexType in the soapcpp2-generated schema with targetNamespace "urn:types", elementFormDefault qualified and attributeFormDefault unqualified:
<schema targetNamespace="urn:types"
...
elementFormDefault="qualified"
attributeFormDefault="unqualified"
... >
<complexType name="record"> <sequence> <element name="spouse" type="ns:record" minOccurs="0" maxOccurs="1" nillable="true"/> </sequence> <attribute name="name" type="xsd:string" use="required"/> <attribute name="SSN" type="xsd:unsignedLong" use="required"/> </complexType></schema>
An example XML instance of
ns__recordis:
<ns:record xmlns:ns="urn:types" name="Joe" SSN="1234567890"> <ns:spouse> name="Jane" SSN="1987654320"> </ns:spouse> </ns:record>
Note that the root element ns:record is qualified because it is a root element of the schema with target namespace "urn:types". Its local element ns:spouse is namespace qualified because the elementFormDefault of local elements is qualified. Attributes are
unqualified.
The default namespace (un)qualification of local elements and attributes can be overruled by adding a prefix to the member name by using colon notation:
//gsoap ns schema namespace: urn:types
//gsoap ns schema elementForm: qualified
//gsoap ns schema attributeForm: unqualified
class
ns__record
{
public:
@std::string ns:name;
// 'ns:' qualified
@uint64_t SSN;
ns__record *:spouse;
// ':' unqualified (empty prefix)
};
The colon notation for member
ns:nameforces
qualification of its attribute tag in XML. The colon notation for member
:spouseremoves
qualification from its local element tag:
<schema targetNamespace="urn:types" ... elementFormDefault="unqualified" attributeFormDefault="unqualified" ... > <complexType name="record"> <sequence> <element name="spouse" type="ns:record" minOccurs="0" maxOccurs="1" nillable="true" form="unqualified"/> </sequence> <attribute name="name" type="xsd:string" use="required" form="qualified"/> <attribute name="SSN" type="xsd:unsignedLong" use="required"/> </complexType> </schema>
XML instances of
ns__recordhave
unqualified spouse elements and qualified ns:name attributes:
<ns:record xmlns:ns="urn:types" ns:name="Joe" SSN="1234567890"> <spouse> ns:name="Jane" SSN="1987654320"> </spouse> </ns:record>
Note that data members can also be prefixed using the
prefix__nameconvention.
However, this has a different effect by referring to global (root) elements and attributes, see document root element
definitions.
Backtick tag names can be used in place of the member name annotations and will achieve the same effect as described
when these tag names are (un)qualified (requires gSOAP 2.8.30 or higher).
NoteYou must declare a target namespace with a
//gsoap ns schema namespace:directive to enable the
elementFormand
attributeFormdirectives
in order to generate valid schemas with soapcpp2. See directives for more details.
Defining document root elements
To define and reference XML document root elements we use type names that start with an underscore:class
_ns__record
Alternatively, we can use a typedef to define a document root element with a given type:
typedef ns__record _ns__record;
This typedef maps to a global root element that is added to the soapcpp2-generated schema:
<element name="record" type="ns:record"/>
An example XML instance of
_ns__recordis:
<ns:record xmlns:ns="urn:types"> <name>Joe</name> <SSN>1234567890</SSN> <spouse> <name>Jane</name> <SSN>1987654320</SSN> </spouse> </ns:record>
Global-level element/attribute definitions are also referenced and/or added to the generated schema when serializable data members reference these by their qualified name:
typedef std::string _ns__name 1 : 100;
class
_ns__record
{
public:
@_QName xsi__type;
// built-in XSD attribute xsi:type
_ns__name ns__name;
// ref to global ns:name element
uint64_t SSN;
_ns__record *spouse;
};
These types map to the following comonents in the soapcpp2-generated schema:
<simpleType name="name">
<restriction base="xsd:string">
<minLength value="1"/>
<maxLength value="100"/>
</restriction>
</simpleType>
<element name="name" type="ns:name"/>
<complexType name="record">
<sequence>
<element ref="ns:name" minOccurs="1" maxOccurs="1"/>
<element name="SSN" type="xsd:unsignedLong" minOccurs="1" maxOccurs="1"/>
<element name="spouse" type="ns:record" minOccurs="0" maxOccurs="1" nillable="true"/>
</sequence>
<attribute ref="xsi:type" use="optional"/>
</complexType>
<element name="record" type="ns:record"/>
Use only use qualified member names when their types match the global-level element types that they refer to. For example:
typedef std::string _ns__name;
// global element ns:name of type xsd:string
class
_ns__record
{
public: int ns__name;
// BAD: global element ns:name is NOT type int
_ns__record ns__record;
// OK: ns:record is a global-level root element
...
};
Therefore, we recommend to use qualified member names only when necessary to refer to standard XSD elements and attributes, such as
xsi__type,
and
xsd__lang.
By contrast, colon notation has the desired effect to (un)qualify local tag names by overruling the default element/attribute namespace qualification, see qualified
and unqualified members.
As an alternative to prefixing member names, use the backtick tag (gSOAP 2.8.30 and higher):
typedef std::string _ns__name 1 : 100;
class
_ns__record
{
public:
@_QName t `xsi:type`;
// built-in XSD attribute xsi:type
_ns__name s `ns:name`;
// ref to global ns:name element
uint64_t SSN;
_ns__record *spouse;
};
(Smart) pointer members and their occurrence constraints
A public pointer-typed data member is serialized by following its (smart) pointer(s) to the value pointed to. To serialize pointers to dynamic arrays of data, please see the next section on containermembers and their occurrence constraints.
Pointers that are NULL and smart pointers that are empty are serialized to produce omitted element and attribute values, unless an element is required and is nillable.
To control the occurrence requirements of pointer-based data members, occurrence constraints are associated with data members in the form of a range
minOccurs : maxOccurs. For non-repeatable (meaning, not a container or array) data members, there are only three reasonable occurrence constraints:
0:0means that this element or attribute
is prohibited.
0:1means that this element or attribute
is optional.
1:1means that this element or attribute
is required.
Pointer-based data members have a default
0:1occurrence
constraint, making them optional, and their XML schema local element/attribute definition is marked as nillable. Non-pointer data members have a default
1:1occurence
constraint, making them required.
A pointer data member that is explicitly marked as required with
1:1will
be serialized as an element with an
xsi:nilattribute,
thus effectively revealing the NULL property of its value.
A non-pointer data member that is explicitly marked as optional with
0:1will
be set to its default value when no XML value is presented to the deserializer. A default value can be assigned to data members that have primitive types.
Consider for example:
class
ns__record
{
public:
std::shared_ptr<std::string> name;
// optional (0:1)
uint64_t SSN 0:1 = 999;
// forced this to be optional with default 999
ns__record *spouse 1:1;
// forced this to be required (only married people)
};
This class maps to a complexType in the soapcpp2-generated schema:
<complexType name="record"> <sequence> <element name="name" type="xsd:string" minOccurs="0" maxOccurs="1" nillable="true"/> <element name="SSN" type="xsd:unsignedLong" minOccurs="0" maxOccurs="1" default="999"/> <element name="spouse" type="ns:record" minOccurs="1" maxOccurs="1" nillable="true"/> </sequence> </complexType>
An example XML instance of
ns__recordwith
its
namestring value set to
Joe,
SSNset
to its default, and
spouseset to NULL:
<ns:record xmlns:ns="urn:types" ...> <name>Joe</name> <SSN>999</SSN> <spouse xsi:nil="true"/> </ns:record>
NoteIn general, a smart pointer is simply declared as a
volatiletemplate
in a gSOAP header file for soapcpp2:
volatile
template <class T>
class NAMESPACE::shared_ptr;
NoteThe soapcpp2 tool generates code that uses
NAMESPACE::shared_ptrand
NAMESPACE::make_sharedto
create shared pointers to objects, where
NAMESPACEis
any valid C++ namespace such as
stdand
boostif
you have Boost installed.
Container members and their occurrence constraints
Class and struct data member types that are containersstd::deque,
std::list,
std::vectorand
std::setare
serialized as a collection of the values they contain. You can also serialize dynamic arrays, which is the alternative for C to store collections of data. Let's start with STL containers.
You can use
std::deque,
std::list,
std::vector,
and
std::setcontainers by importing:
#import "import/stl.h"
// import all containers
#import "import/stldeque.h"
// import deque
#import "import/stllist.h"
// import list
#import "import/stlvector.h"
// import vector
#import "import/stlset.h"
// import set
For example, to use a vector data mamber to store names in a record:
#import "import/stlvector.h"
class
ns__record
{
public:
std::vector<std::string> names;
uint64_t SSN;
};
To limit the number of names in the vector within reasonable bounds, occurrence constraints are associated with the container. Occurrence constraints are of the form
minOccurs : maxOccurs:
#import "import/stlvector.h"
class
ns__record
{
public:
std::vector<std::string> names 1:10;
uint64_t SSN;
};
This class maps to a complexType in the soapcpp2-generated schema:
<complexType name="record"> <sequence> <element name="name" type="xsd:string" minOccurs="1" maxOccurs="10"/> <element name="SSN" type="xsd:unsignedLong" minOccurs="1" maxOccurs="1""/> </sequence> </complexType>
NoteIn general, a container is simply declared as a template in a gSOAP header file for soapcpp2. All class templates are considered containers (except when declared
volatile,
see smart pointers). For example,
std::vectoris
declared in
gsoap/import/stlvector.has:
template <class T>
class std::vector;
NoteYou can define and use your own containers. The soapcpp2 tool generates code that uses the following members of the
template <typename T> class Ccontainer:
void C::clear()
C::iterator C::begin()
C::const_iterator C::begin() const
C::iterator C::end()
C::const_iterator C::end() const
size_t C::size() const
C::iterator C::insert(C::iterator pos, const T& val)
NoteFor more details see the example
simple_vectorcontainer
with documentation in the package under
gsoap/samples/template.
Because C does not support a container template library, we can use a dynamically-sized array of values. This array is declared as a size-pointer pair of members within a struct or class. The array size information is stored in a special size tag member
with the name
__sizeor
__sizeX,
where
Xcan be any name, or by an
$intmember
to identify the member as a special size tag:
struct
ns__record
{
$int sizeofnames;
// array size
char* *names;
// array of char* names
uint64_t SSN;
};
This class maps to a complexType in the soapcpp2-generated schema:
<complexType name="record"> <sequence> <element name="name" type="xsd:string" minOccurs="0" maxOccurs="unbounded" nillable="true"/> <element name="SSN" type="xsd:unsignedLong" minOccurs="1" maxOccurs="1""/> </sequence> </complexType>
To limit the number of names in the array within reasonable bounds, occurrence constraints are associated with the array size member. Occurrence constraints are of the form
minOccurs : maxOccurs:
struct
ns__record
{
$int sizeofnames 1:10;
// array size 1..10
char* *names;
// array of one to ten char* names
uint64_t SSN;
};
This class maps to a complexType in the soapcpp2-generated schema:
<complexType name="record"> <sequence> <element name="name" type="xsd:string" minOccurs="1" maxOccurs="10" nillable="true"/> <element name="SSN" type="xsd:unsignedLong" minOccurs="1" maxOccurs="1""/> </sequence> </complexType>
Tagged union members
A union member in a class or in a struct cannot be serialized unless a discriminating variant selector member is provided that tells the serializer which union field to serialize. This effectively creates a tagged union.The variant selector is associated with the union as a selector-union pair of members. The variant selector is a member with the name
__unionor
__unionX,
where
Xcan be any name, or by an
$intmember
to identify the member as a variant selector tag:
class
ns__record
{
public:
$int xORnORs;
// variant selector with values SOAP_UNION_fieldname
union
choice
{
float x;
int n;
char *s;
} u;
std::string name;
};
The variant selector values are auto-generated based on the union name
choiceand
the names of its members
x,
n,
and
s:
xORnORs = SOAP_UNION_choice_xwhen
u.xis
valid.
xORnORs = SOAP_UNION_choice_nwhen
u.nis
valid.
xORnORs = SOAP_UNION_choice_swhen
u.sis
valid.
xORnORs = 0when none are valid
(should only be used with great care, because XML content validation may fail when content is required but absent).
This class maps to a complexType with a sequence and choice in the soapcpp2-generated schema:
<complexType name="record"> <sequence> <choice> <element name="x" type="xsd:float" minOccurs="1" maxOccurs="1"/> <element name="n" type="xsd:int" minOccurs="1" maxOccurs="1"/> <element name="s" type="xsd:string" minOccurs="0" maxOccurs="1" nillable="true"/> </choice> <element name="names" type="xsd:string" minOccurs="1" maxOccurs="1" nillable="true"/> </sequence> </complexType>
An STL container or dynamic array of a union requires wrapping the variant selector and union member in a struct:
class
ns__record
{
public:
std::vector<
struct
ns__data // data with a choice of x, n, or s
{
$int xORnORs;
// variant selector with values SOAP_UNION_fieldname
union
choice
{
float x;
int n;
char *s;
} u;
}> data;
// vector with data
};
and an equivalent definition with a dynamic array instead of a
std::vector(you
can use this in C with structs):
class
ns__record
{
public:
$int sizeOfdata;
// size of dynamic array
struct
ns__data // data with a choice of x, n, or s
{
$int xORnORs;
// variant selector with values SOAP_UNION_fieldname
union
choice
{
float x;
int n;
char *s;
} u;
} *data;
// points to the data array of length sizeOfdata
};
This maps to two complexTypes in the soapcpp2-generated schema:
<complexType name="data"> <choice> <element name="x" type="xsd:float" minOccurs="1" maxOccurs="1"/> <element name="n" type="xsd:int" minOccurs="1" maxOccurs="1"/> <element name="s" type="xsd:string" minOccurs="0" maxOccurs="1" nillable="true"/> </choice> </complexType> <complexType name="record"> <sequence> <element name="data" type="ns:data" minOccurs="0" maxOccurs="unbounded"/> </sequence> </complexType>
The XML value space consists of a sequence of item elements each wrapped in an data element:
<ns:record xmlns:ns="urn:types" ...> <data> <n>123</n> </data> <data> <x>3.1</x> </data> <data> <s>hello</s> </data> <data> <s>world</s> </data> </ns:record>
To remove the wrapping data element, simply rename the wrapping struct and member to
__datato
make this member invisible to the serializer with the double underscore prefix naming convention. Also use a dynamic array instead of a STL container (you can use this in C with structs):
class
ns__record
{
public:
$int sizeOfdata;
// size of dynamic array
struct
__data // contains choice of x, n, or s
{
$int xORnORs;
// variant selector with values SOAP_UNION_fieldname
union
choice
{
float x;
int n;
char *s;
} u;
} *__data;
// points to the data array of length sizeOfdata
};
This maps to a complexType in the soapcpp2-generated schema:
<complexType name="record"> <sequence minOccurs="0" maxOccurs="unbounded"> <choice> <element name="x" type="xsd:float" minOccurs="1" maxOccurs="1"/> <element name="n" type="xsd:int" minOccurs="1" maxOccurs="1"/> <element name="s" type="xsd:string" minOccurs="0" maxOccurs="1" nillable="true"/> </choice> </sequence> </complexType>
The XML value space consists of a sequence of
<x>,
<n>,
and/or
<s>elements:
<ns:record xmlns:ns="urn:types" ...> <n>123</n> <x>3.1</x> <s>hello</s> <s>world</s> </ns:record>
Please note that structs, classes, and unions are unnested by soapcpp2 (as in the C standard of nested structs and unions). Therefore, the
choiceunion
in the
ns__recordclass is redeclared
at the top level despite its nesting within the
ns__recordclass.
This means that you will have to choose a unique name for each nested struct, class, and union.
Tagged void pointer members
To serialize data pointed to byvoid*requires
run-time type information that tells the serializer what type of data to serialize by means of a tagged void pointer. This type information is stored in a special type tag member of a struct/class with the name
__typeor
__typeX,
where
Xcan be any name, or alternatively
by an
$intspecial member of any name
as a type tag:
class
ns__record
{
public:
$int typeOfdata;
// type tag with values SOAP_TYPE_Tvoid *data;
// points to some data of type T};
A type tag member has nonzero values
SOAP_TYPE_Twhere
Tis
the name of a struct/class or the name of a primitive type, such as
int,
std__string(for
std::string),
string(for
char*).
This class maps to a complexType with a sequence in the soapcpp2-generated schema:
<complexType name="record"> <sequence> <element name="data" type="xsd:anyType" minOccurs="0" maxOccurs="1"/> </sequence> </complexType>
The XML value space consists of the XML value space of the type with the addition of an
xsi:typeattribute
to the enveloping element:
<ns:record xmlns:ns="urn:types" ...> <data xsi:type="xsd:int">123</data> </ns:record>
This
xsi:typeattribute is important
for the receiving end to distinguish the type of data to instantiate. The receiver cannot deserialize the data without an
xsd:typeattribute.
You can find the
SOAP_TYPE_Tname
of each serializable type in the auto-generated soapStub.h file.
Also all serializable C++ classes have a virtual
int T::soap_type()member that returns their
SOAP_TYPE_Tvalue
that you can use.
When the
void*pointer is NULL or
when
typeOfdatais zero, the data is
not serialized.
An STL container or dynamic array of
void*pointers
to
xsd:anyTypedata requires wrapping
the type tag and
void*members in a
struct:
class
ns__record
{
public:
std::vector<
struct
ns__data // data with an xsd:anyType item
{
$int typeOfitem;
// type tag with values SOAP_TYPE_Tvoid *item;
// points to some item of type T}> data;
// vector with data
};
and an equivalent definition with a dynamic array instead of a
std::vector(you
can use this in C with structs):
class
ns__record
{
public:
$int sizeOfdata;
// size of dynamic array
struct
ns__data // data with an xsd:anyType item
{
$int typeOfitem;
// type tag with values SOAP_TYPE_Tvoid *item;
// points to some item of type T} *data;
// points to the data array of length sizeOfdata
};
This maps to two complexTypes in the soapcpp2-generated schema:
<complexType name="data"> <sequence> <element name="item" type="xsd:anyType" minOccurs="1" maxOccurs="1" nillable="true"/> </sequence> </complexType> <complexType name="record"> <sequence> <element name="data" type="ns:data" minOccurs="0" maxOccurs="unbounded"/> </sequence> </complexType>
The XML value space consists of a sequence of item elements each wrapped in a data element:
<ns:record xmlns:ns="urn:types" ...> <data> <item xsi:type="xsd:int">123</item> </data> <data> <item xsi:type="xsd:double">3.1</item> </data> <data> <item xsi:type="xsd:string">abc</item> </data> </ns:record>
To remove the wrapping data elements, simply rename the wrapping struct and member to
__datato
make this member invisible to the serializer with the double underscore prefix naming convention. Also use a dynamic array instead of a STL container (you can use this in C with structs):
class
ns__record
{
public:
$int sizeOfdata;
// size of dynamic array
struct
__data // contains xsd:anyType item
{
$int typeOfitem;
// type tag with values SOAP_TYPE_Tvoid *item;
// points to some item of type T} *__data;
// points to the data array of length sizeOfdata
};
This maps to a complexType in the soapcpp2-generated schema:
<complexType name="record"> <sequence minOccurs="0" maxOccurs="unbounded"> <element name="item" type="xsd:anyType" minOccurs="1" maxOccurs="1"/> </sequence> </complexType>
The XML value space consists of a sequence of data elements:
<ns:record xmlns:ns="urn:types" ...> <item xsi:type="xsd:int">123</item> <item xsi:type="xsd:double">3.1</item> <item xsi:type="xsd:string">abc</item> </ns:record>
Again, please note that structs, classes, and unions are unnested by soapcpp2 (as in the C standard of nested structs and unions). Therefore, the
__datastruct
in the
ns__recordclass is redeclared
at the top level despite its nesting within the
ns__recordclass.
This means that you will have to choose a unique name for each nested struct, class, and union.
See alsoSection XSD type bindings.
Adding get and set methods
A publicgetmethod may be added
to a class or struct, which will be triggered by the deserializer. This method will be invoked right after the instance is populated by the deserializer. The
getmethod
can be used to update or verify deserialized content. It should return
SOAP_OKor
set
soap::errorto a nonzero error
code and return it.
A public
setmethod may be added
to a class or struct, which will be triggered by the serializer. The method will be invoked just before the instance is serialized. Likewise, the
setmethod
should return
SOAP_OKor set set
soap::errorto
a nonzero error code and return it.
For example, adding a
setand
getmethod
to a class declaration:
class
ns__record
{
public: int set(struct soap*);
// triggered before serialization
int
get(struct soap*); // triggered after deserialization
...
};
To add these and othe rmethods to classes and structs with wsdl2h and
typemap.dat,
please see class/struct member additions.
Operations on classes and structs
The following functions/macros are generated by soapcpp2 for each typeT,
which should make it easier to send, receive, and copy XML data in C and in C++:
int soap_write_T(struct soap*, T*)writes
an instance of
Tto a file via file
descriptor
int soap::sendfd)or to
a stream via
std::ostream *soap::os(C++
only) or saves into a NUL-terminated string by setting
const char **soap::osto a string pointer to be set (C only). Returns
SOAP_OKon
success or an error code, also stored in
soap->error.
int soap_read_T(struct soap*, T*)reads
an instance of
Tfrom a file via file
descriptor
int soap::recvfd)or from
a stream via
std::istream *soap::is(C++
only) or reads from a NUL-termianted string
const char *soap::is(C only). Returns
SOAP_OKon
success or an error code, also stored in
soap->error.
void soap_default_T(struct soap*, T*)sets
an instance
Tto its default value,
resetting members of a struct to their initial values (for classes we use method
T::soap_default,
see below).
T * soap_dup_T(struct soap*, T *dst, const T *src)(soapcpp2 option
-Ec)
deep copy
srcinto
dst,
replicating all deep cycles and shared pointers when a managing soap context is provided as argument. When
dstis
NULL, allocates space for
dst. Deep
copy is a tree when argument is NULL, but the presence of deep cycles will lead to non-termination. Use flag
SOAP_XML_TREEwith
managing context to copy into a tree without cycles and pointers to shared objects. Returns
dst(or
allocated space when
dstis NULL).
void soap_del_T(const T*)(soapcpp2
option
-Ed) deletes all heap-allocated
members of this object by deep deletion ONLY IF this object and all of its (deep) members are not managed by a soap context AND the deep structure is a tree (no cycles and co-referenced objects by way of multiple (non-smart) pointers pointing to the same data).
Can be safely used after
soap_dup(NULL)to
delete the deep copy. Does not delete the object itself.
When in C++ mode, soapcpp2 tool adds several methods to classes in addition to adding a default constructor and destructor (when these were not explicitly declared).
The public methods added to a class
T:
virtual int T::soap_type(void)returns
a unique type ID (
SOAP_TYPE_T). This
numeric ID can be used to distinguish base from derived instances.
virtual void T::soap_default(struct soap*)sets
all data members to default values.
virtual void T::soap_serialize(struct soap*) constserializes object to prepare for SOAP 1.1/1.2 encoded output (or with
SOAP_XML_GRAPH)
by analyzing its (cyclic) structures.
virtual int T::soap_put(struct soap*, const char *tag, const char *type) constemits object in XML, compliant with SOAP 1.1 encoding style, return error code or
SOAP_OK.
Requires
soap_begin_send(soap)and
soap_end_send(soap).
virtual int T::soap_out(struct soap*, const char *tag, int id, const char *type) constemits object in XML, with tag and optional id attribute and
xsi:type,
return error code or
SOAP_OK. Requires
soap_begin_send(soap)and
soap_end_send(soap).
virtual void * T::soap_get(struct soap*, const char *tag, const char *type)Get object from XML, compliant with SOAP 1.1 encoding style, return pointer to object or NULL on error. Requires
soap_begin_recv(soap)and
soap_end_recv(soap).
virtual void *soap_in(struct soap*, const char *tag, const char *type)Get object from XML, with matching tag and type (NULL matches any tag and type), return pointer to object or NULL on error. Requires
soap_begin_recv(soap)and
soap_end_recv(soap)
virtual T * T::soap_alloc(void) constreturns
a new object of type
T, default initialized
and not managed by a soap context.
virtual T * T::soap_dup(struct soap*) const(soapcpp2
option
-Ec) returns a duplicate of
this object by deep copying, replicating all deep cycles and shared pointers when a managing soap context is provided as argument. Deep copy is a tree when argument is NULL, but the presence of deep cycles will lead to non-termination. Use flag
SOAP_XML_TREEwith
the managing context to copy into a tree without cycles and pointers to shared objects.
virtual void T::soap_del() const(soapcpp2
option
-Ed) deletes all heap-allocated
members of this object by deep deletion ONLY IF this object and all of its (deep) members are not managed by a soap context AND the deep structure is a tree (no cycles and co-referenced objects by way of multiple (non-smart) pointers pointing to the same data).
Can be safely used after
soap_dup(NULL)to
delete the deep copy. Does not delete the object itself.
Also for C++, there are four variations of
soap_new_Tfor
class/struct/template type
Tthat soapcpp2
auto-generates to create instances on a context-managed heap:
T * soap_new_T(struct soap*)returns
a new instance of
Twith default data
member initializations that are set with the soapcpp2 auto-generated
void T::soap_default(struct soap*)method), but ONLY IF the soapcpp2 auto-generated default constructor is used that invokes
soap_default()and
was not replaced by a user-defined default constructor.
T * soap_new_T(struct soap*, int n)returns
an array of
nnew instances of
T.
Similar to the above, instances are initialized.
T * soap_new_req_T(struct soap*, ...)returns
a new instance of
Tand sets the required
data members to the values specified in
....
The required data members are those with nonzero minOccurs, see the subsections on (smart) pointer members and their
occurrence constraints and container members and their occurrence constraints.
T * soap_new_set_T(struct soap*, ...)returns
a new instance of
Tand sets the public/serializable
data members to the values specified in
....
The above functions can be invoked with a NULL
soapcontext,
but we will be responsible to use
delete Tto
remove this instance from the unmanaged heap.
Special classes and structs
SOAP encoded arrays
A class or struct with the following layout is a one-dimensional SOAP encoded Array type:class
ArrayOfT{
public:
T *__ptr;
// array pointer
int __size;
// array size
};
where
Tis the array element type.
A multidimensional SOAP Array is:
class
ArrayOfT{
public:
T *__ptr;
// array pointer
int __size
;
// array size of each dimension
};
where
Nis the constant number of
dimensions. The pointer points to an array of
__size[0]*__size[1]* ... * __size[N-1]elements.
This maps to a complexType restriction of SOAP-ENC:Array in the soapcpp2-generated schema:
<complexType name="ArrayOfT"> <complexContent> <restriction base="SOAP-ENC:Array"> <sequence> <element name="item" type="T" minOccurs="0" maxOccurs="unbounded" nillable="true"/> </sequence> <attribute ref="SOAP-ENC:arrayType" WSDL:arrayType="ArrayOfT[]"/> </restriction> </complexContent> </complexType>
The name of the class can be arbitrary. We often use
ArrayOfTwithout
a prefix to distinguish arrays from other classes and structs.
With SOAP 1.1 encoding, an optional offset member can be added that controls the start of the index range for each dimension:
class
ArrayOfT{
public:
T *__ptr;
// array pointer
int __size
;
// array size of each dimension
int __offset
;
// array offsets to start each dimension
};
For example, we can define a matrix of floats as follows:
class
Matrix
{
public:
double *__ptr;
int __size[2];
};
The following code populates the matrix and serializes it in XML:
soap *soap = soap_new1(SOAP_XML_INDENT);
Matrix A;
double a[6] = { 1, 2, 3, 4, 5, 6 };
A.__ptr = a;
A.__size[0] = 2;
A.__size[1] = 3;
soap_write_Matrix(soap, &A);
Matrix A is serialized as an array with 2x3 values:
<SOAP-ENC:Array SOAP-ENC:arrayType="xsd:double[2,3]" ...> <item>1</item> <item>2</item> <item>3</item> <item>4</item> <item>5</item> <item>6</item> </SOAP-ENC:Array>
XSD hexBinary and base64Binary types
A special case of a one-dimensional array is used to definexsd:hexBinaryand
xsd:base64Binarytypes
when the pointer type is
unsigned char:
class
xsd__hexBinary
{
public:
unsigned
char *__ptr;
// points to raw binary data
int __size;
// size of data
};
and
class
xsd__base64Binary
{
public:
unsigned
char *__ptr;
// points to raw binary data
int __size;
// size of data
};
MIME/MTOM attachment binary types
A class or struct with a binary content layout can be extended to support MIME/MTOM (and older DIME) attachments, such as in xop:Include elements://gsoap xop schema import: http://www.w3.org/2004/08/xop/include class
_xop__Include
{
public:
unsigned
char *__ptr;
// points to raw binary data
int __size;
// size of data
char *id;
// NULL to generate an id, or set to a unique UUID
char *type;
// MIME type of the data
char *options;
// optional description of MIME attachment
};
Attachments are beyond the scope of this document. The
SOAP_ENC_MIMEand
SOAP_ENC_MTOMcontext
flag must be set to enable attachments. See the gSOAP user guide for more details.
Wrapper class/struct with simpleContent
A class or struct with the following layout is a complexType that wraps simpleContent:class
ns__simple
{
public:
T __item;
};
The type
Tis a primitive type (
bool,
enum,
time_t,
numeric and string types),
xsd__hexBinary,
xsd__base64Binary,
and custom serializers, such as
xsd__dateTime.
This maps to a complexType with simpleContent in the soapcpp2-generated schema:
<complexType name="simple"> <simpleContent> <extension base="T"/> </simpleContent> </complexType>
A wrapper class/struct may include any number of attributes declared with
@.
DOM anyType and anyAttribute
Use of a DOM is optional and enabled by#import "dom.h"to use the DOM
xsd__anyTypeelement
node and
xsd__anyAttributeattribute
node:
#import "dom.h"
class
ns__record
{
public:
@xsd__anyAttribute attributes;
// list of DOM attributes
...
xsd__anyType *name;
// optional DOM element
};
where
namecontains XML stored in
a DOM node set and
attributesis a
list of all visibly rendered attributes. The name
attributesis
arbitrary and any name will suffice.
You should place the
xsd__anyTypemembers
at the end of the struct or class. This ensures that the DOM members are populated last as a "catch all". A member name starting with double underscore is a wildcard member name and matches any XML tag. These members are placed at the end of a struct or class
automatically by soapcpp2.
An
#import "dom.h"import is automatically
added by wsdl2h with option
-dto bind
xsd:anyTypeto
DOM nodes, and also to populate
xsd:any,
xsd:anyAttributeand
xsd:mixedXML
content:
#import "dom.h"
class
ns__record
{
public:
...
@xsd__anyAttribute __anyAttribute;
// optional DOM attributes
std::vector<xsd__anyType> __any 0;
// optional DOM elements
xsd__anyType __mixed 0;
// optional mixed content
};
where the members prefixed with
__are
"invisible" to the XML parser, meaning that these members are not bound to XML tag names.
In C you can use a dynamic arrary instead of
std::vector:
#import "dom.h"
struct
ns__record
{
...
@xsd__anyAttribute __anyAttribute;
// optional DOM attributes
$int __sizeOfany;
// size of the array
xsd__anyType *__any;
// optional DOM elements
xsd__anyType __mixed 0;
// optional mixed content
};
Classes can inherit DOM, which enables full use of polymorphism with one base DOM class:
#import "dom.h"
class
ns__record : public xsd__anyType
{
...
std::vector<xsd__anyType*> array;
// array of objects of any class
};
This permits an
xsd__anyTypepointer
to refer to a derived class such as
ns__record,
which will be serialized with an
xsi:typeattribute
that is set to "ns:record". The
xsi:typeattributes
add the necessary type information to distinguish the XML content from the DOM base type. This is important for the receiving end: without
xsd:typeattributes
with type names, only base DOM objects are recognized and instantiated.
Because C lacks OOP principles such as class inheritance and polymorphism, you will need to use the special `void*`
members to serialize data pointed to by a
void*member.
To ensure that wsdl2h generates pointer-based
xsd__anyTypeDOM
nodes with option
-dfor
xsd:any,
add the following line to
typemap.dat:
xsd__any = | xsd__anyType*
This lets wsdl2h produce class/struct members and containers with
xsd__anyType*for
xsd:anyinstead
of
xsd__anyType. To just force all
xsd:anyTypeuses
to be pointer-based, declare in
typemap.dat:
xsd__anyType = | xsd__anyType*
If you use wsdl2h with option
-pwith
option
-dthen every class will inherit
DOM as shown above. Without option
-d,
an
xsd__anyTypetype is generated to
serve as the root type in the type hierarchy:
class
xsd__anyType {
_XML __item; struct soap *soap; };
class
ns__record : public xsd__anyType
{
...
};
where the
_XML __itemmember holds
any XML content as a literal XML string.
To use the DOM API, compile
dom.c(or
dom.cppfor
C++), or link with
-lgsoapssl(or
-lgsoapssl++for
C++).
See alsoDocumentation of XML DOM and XPath for more details.
Directives
You can use//gsoapdirectives in
the gSOAP header file with the data binding interface for soapcpp2. These directives are used to configure the code generated by soapcpp2 by declaring various. properties of Web services and XML schemas. When using the wsdl2h tool, you will notice that wsdl2h
generates directives automatically based on the WSDL and XSD input.
Service directives are applicable to service and operations described by WSDL. Schema directives are applicable to types, elements, and attributes defined by XML schemas.
Service directives
A service directive must start at a new line and is of the form://gsoap <prefix> service <property>: <value>
where
<prefix>is the XML namespace
prefix of a service binding. The
<property>and
<value>fields
are one of the following:
| Property | Value |
|---|---|
name | name of the service, optionally followed by text describing the service |
namespace | URI of the WSDL targetNamespace |
documentation | text describing the service (see also the nameproperty), multiple permitted |
doc | same as above, shorthand form |
style | document(default) SOAP messaging style or rpcfor SOAP RPC |
encoding | literal(default), encodedfor SOAP encoding, or a custom URI |
protocol | specifies SOAP or REST, see below |
port | URL of the service endpoint, usually an http or https address |
transport | URI declaration of the transport, usually http://schemas.xmlsoap.org/soap/http |
definitions | name of the WSDL definitions/@name |
type | name of the WSDL definitions/portType/@name (WSDL2.0 interface/@name) |
binding | name of the WSDL definitions/binding/@name |
portName | name of the WSDL definitions/service/port/@name |
portType | an alias for the typeproperty |
interface | an alias for the typeproperty |
location | an alias for the portproperty |
endpoint | an alias for the portproperty |
nameand
namespaceproperties
are required in order to generate a valid WSDL with soapcpp2. The other properties are optional.
The
styleand
encodingproperty
defaults are changed with soapcpp2 option
-eto
rpcand
encoded,
respectively.
The
protocolproperty is
SOAPby
default (SOAP 1.1). Protocol property values are:
| Protocol Value | Description |
|---|---|
SOAP | SOAP transport, supporting both SOAP 1.1 and 1.2 |
SOAP1.1 | SOAP 1.1 transport (same as soapcpp2 option -1) |
SOAP1.2 | SOAP 1.2 transport (same as soapcpp2 option -2) |
SOAP-GET | one-way SOAP 1.1 or 1.2 with HTTP GET |
SOAP1.1-GET | one-way SOAP 1.1 with HTTP GET |
SOAP1.2-GET | one-way SOAP 1.2 with HTTP GET |
HTTP | non-SOAP REST protocol with HTTP POST |
POST | non-SOAP REST protocol with HTTP POST |
GET | non-SOAP REST protocol with HTTP GET |
PUT | non-SOAP REST protocol with HTTP PUT |
DELETE | non-SOAP REST protocol with HTTP DELETE |
int prefix__func(arg1, arg2, ..., argn, result);
You can override the
portendpoint
URL at runtime in the auto-generated
soap_call_prefix__funcservice
call (C/C++ client side) and in the C++ proxy class service call.
Service method directives
Service properties are applicable to a service and to all of its operations. Service method directives are specifically applicable to a service operation.A service method directive is of the form:
//gsoap <prefix> service method-<property>: <method> <value>
where
<prefix>is the XML namespace
prefix of a service binding and
<method>is
the unqualified name of a service operation. The
<property>and
<value>fields
are one of the following:
| Method Property | Value |
|---|---|
method-documentation | text describing the service operation |
method | same as above, shorthand form |
method-action | ""or URI SOAPAction HTTP header, or URL query string for REST protocols |
method-input-action | ""or URI SOAPAction HTTP header of service request messages |
method-output-action | ""or URI SOAPAction HTTP header of service response messages |
method-fault-action | ""or URI SOAPAction HTTP header of service fault messages |
method-header-part | member name of the SOAP_ENV__Headerstruct used in SOAP Header |
method-input-header-part | member name of the SOAP_ENV__Headerstruct used in SOAP Headers of requests |
method-output-header-part | member name of the SOAP_ENV__Headerstruct used in SOAP Headers of responses |
method-fault | type name of a struct or class member used in SOAP_ENV__Detailsstruct |
method-mime-type | REST content type or SOAP MIME attachment content type(s) |
method-input-mime-type | REST content type or SOAP MIME attachment content type(s) of request message |
method-output-mime-type | REST content type or SOAP MIME attachment content type(s) of response message |
method-style | documentor rpc |
method-encoding | literal, encoded, or a custom URI for encodingStyle of messages |
method-response-encoding | literal, encoded, or a custom URI for encodingStyle of response messages |
method-protocol | SOAP or REST, see service directives |
method-header-partproperties
can be repeated for a service operation to declare multiple SOAP Header parts that the service operation requires. You can use
method-input-header-partand
method-output-header-partto
differentiate between request and response messages.
The
method-faultproperty can be
repeated for a service operation to declare multiple faults that the service operation may return.
The
method-actionproperty serves
two purposes:
To set the SOAPAction header for SOAP protocols, i.e. sets the definitions/binding/operation/SOAP:operation/@soapAction.
To set the URL query string for endpoints with REST protocols, i.e. sets the definitions/binding/operation/HTTP:operation/@location, which specifies a URL query string (starts with a
?)
to complete the service endpoint URL or extends the endpoint URL with a local path (starts with a
/).
Use
method-input-actionand
method-output-actionto
differentiate the SOAPAction between SOAP request and response messages.
You can always override the port endpoint URL and action values at runtime in the auto-generated
soap_call_prefix__funcservice
call (C/C++ client side) and in the auto-generated C++ proxy class service calls. A runtime NULL endpoint URL and/or action uses the defaults set by these directives.
The
method-mime-typeproperty serves
two purposes:
To set the type of MIME/MTOM attachments used with SOAP protocols. Multiple attachment types can be declared for a SOAP service operation, i.e. adds definitions/binding/operation/input/MIME:multipartRelated/MIME:part/MIME:content/@type for each type specified.
To set the MIME type of a REST operation. This replaces XML declared in WSDL by definitions/binding/operation/(input|output)/MIME:mimeXml with MIME:content/@type. Use
application/x-www-form-urlencodedwith
REST POST and PUT protocols to send encoded form data automatically instead of XML. Only primitive type values can be transmitted with form data, such as numbers and strings, i.e. only types that are legal to use as attributes
members.
Use
method-input-mime-typeand
method-output-mime-typeto
differentiate the attachment types between SOAP request and response messages.
Schema directives
A schema directive is of the form://gsoap <prefix> schema <property>: <value>
where
<prefix>is the XML namespace
prefix of a schema. The
<property>and
<value>fields
are one of the following:
| Property | Value |
|---|---|
namespace | URI of the XSD targetNamespace |
namespace2 | alternate URI for the XSD namespace (i.e. URI is also accepted by the XML parser) |
import | URI of imported namespace |
form | unqualified(default) or qualifiedlocal element and attribute form defaults |
elementForm | unqualified(default) or qualifiedlocal element form default |
attributeForm | unqualified(default) or qualifiedlocal attribute form default |
typed | no(default) or yesfor serializers to add xsi:typeattributes to XML |
The
typedproperty is implicitly
yeswhen
soapcpp2 option
-tis used.
Schema type directives
A schema type directive is of the form://gsoap <prefix> schema type-<property>: <name> <value>
//gsoap <prefix> schema type-<property>: <name>::<member> <value>
where
<prefix>is the XML namespace
prefix of a schema and
<name>is an
unqualified name of a C/C++ type, and the optional
<member>is
a class/struct members or enum constant.
You can describe a type:
| Type Property | Value |
|---|---|
type-documentation | text describing the schema type |
type | same as above, shorthand form |
//gsoap ns schema type: Vowels The letters A, E, I, O, U, and sometimes Y
//gsoap ns schema type: Vowels::Y A vowel, sometimes
enum class ns__Vowels : char { A =
'A', E =
'E', I = 'I', O =
'O', U =
'U', Y = 'Y' };
This documented enumeration maps to a simpleType restriction of
xsd:stringin
the soapcpp2-generated schema:
<simpleType name="Vowels"> <annotation> <documentation>The letters A, E, I, O, U, and sometimes Y</documentation> </annotation> <restriction base="xsd:string"> <enumeration value="A"/> <enumeration value="E"/> <enumeration value="I"/> <enumeration value="O"/> <enumeration value="U"/> <enumeration value="Y"> <annotation> <documentation>A vowel, sometimes</documentation> </annotation> <enumeration/> </restriction> </simpleType>
Serialization rules
A presentation on XML data bindings is not complete without discussing the serialization rules and options that put your data in XML on the wire or store it a file or buffer.There are several options to choose from to serialize data in XML. The choice depends on the use of the SOAP protocol or if SOAP is not required. The wsdl2h tool automates this for you by taking the WSDL transport bindings into account when generating the
service functions in C and C++ that use SOAP or REST.
The gSOAP tools are not limited to SOAP. The tools implement generic XML data bindings for SOAP, REST, and other uses of XML. So you can read and write XML using the serializing operations
on classes and structs.
The following sections briefly explain the serialization rules with respect to the SOAP protocol for XML Web services. A basic understanding of the SOAP protocol is useful when developing client and server applications that must interoperate with other SOAP
applications.
SOAP/REST Web service client and service operations are represented as functions in your gSOAP header file with the data binding interface for soapcpp2. The soapcpp2 tool will translate these function to client-side service invocation calls and server-side
service operation dispatchers.
A discussion of SOAP clients and servers is beyond the scope of this document. However, the SOAP options discussed here also apply to SOAP client and server development.
SOAP document versus rpc style
Thewsdl:binding/soap:binding/@styleattribute
in the wsdl:binding section of a WSDL is either "document" or "rpc". The "rpc" style refers to SOAP RPC (Remote Procedure Call), which is more restrictive than the "document" style by requiring one XML element in the SOAP Body to act as the procedure name
with XML subelements as its parameters.
For example, the following directives in the gSOAP header file for soapcpp2 declare that
DBupdateis
a SOAP RPC encoding service method:
//gsoap ns service namespace: urn:DB
//gsoap ns service method-protocol: DBupdate SOAP
//gsoap ns service method-style: DBupdate rpc
int ns__DBupdate(...);
The XML payload has a SOAP envelope, optional SOAP header, and a SOAP body with one element representing the operation with the parameters as subelements:
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlsn:ns="urn:DB"> <SOAP-ENV:Body> <ns:DBupdate> ... </ns:DBupdate> </SOAP-ENV:Body> </SOAP-ENV:Envelope>
The "document" style puts no restrictions on the SOAP Body content. However, we recommend that the first element's tag name in the SOAP Body should be unique to each type of operation, so that the receiver can dispatch the operation based on this element's
tag name. Alternatively, the HTTP URL path can be used to specify the operation, or the HTTP action header can be used to dispatch operations automatically on the server side (soapcpp2 options -a and -A).
SOAP literal versus encoding
Thewsdl:operation/soap:body/@useattribute
in the wsdl:binding section of a WSDL is either "literal" or "encoded". The "encoded" use refers to the SOAP encoding rules that support id-ref multi-referenced elements to serialize data as graphs.
SOAP encoding is very useful if the data internally forms a graph (including cycles) and we want the graph to be serialized in XML in a format that ensures that its structure is preserved. In that case, SOAP 1.2 encoding is the best option.
SOAP encoding also adds encoding rules for SOAP arrays to serialize multi-dimensional arrays. The use of XML
attributes to exchange XML data in SOAP encoding is not permitted. The only attributes permitted are the standard XSD attributes, SOAP encoding attributes (such as for arrays), and id-ref.
For example, the following directives in the gSOAP header file for soapcpp2 declare that
DBupdateis
a SOAP RPC encoding service method:
//gsoap ns service namespace: urn:DB
//gsoap ns service method-protocol: DBupdate SOAP
//gsoap ns service method-style: DBupdate rpc
//gsoap ns service method-encoding: DBupdate encoded
int ns__DBupdate(...);
The XML payload has a SOAP envelope, optional SOAP header, and a SOAP body with an encodingStyle attribute for SOAP 1.1 encoding and an element representing the operation with parameters that are SOAP 1.1 encoded:
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlsn:ns="urn:DB"> <SOAP-ENV:Body SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"> <ns:DBupdate> <records SOAP-ENC:arrayType="ns:record[3]"> <item> <name href="#_1"/> <SSN>1234567890</SSN> </item> <item> <name>Jane</name> <SSN>1987654320</SSN> </item> <item> <name href="#_1"/> <SSN>2345678901</SSN> </item> </records> </ns:DBupdate> <id id="_1" xsi:type="xsd:string">Joe</id> </SOAP-ENV:Body> </SOAP-ENV:Envelope>
Note that the name "Joe" is shared by two records and the string is referenced by SOAP 1.1 href and id attributes.
While gSOAP only introduces multi-referenced elements in the payload when they are actually multi-referenced in the data graph, other SOAP applications may render multi-referenced elements more aggressively. The example could also be rendered as:
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlsn:ns="urn:DB"> <SOAP-ENV:Body SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"> <ns:DBupdate> <records SOAP-ENC:arrayType="ns:record[3]"> <item href="#id1"/> <item href="#id2"/> <item href="#id3"/> </records> </ns:DBupdate> <id id="id1" xsi:type="ns:record"> <name href="#id4"/> <SSN>1234567890</SSN> </id> <id id="id2" xsi:type="ns:record"> <name href="#id5"/> <SSN>1987654320</SSN> </id> <id id="id3" xsi:type="ns:record"> <name href="#id4"/> <SSN>2345678901</SSN> </id> <id id="id4" xsi:type="xsd:string">Joe</id> <id id="id5" xsi:type="xsd:string">Jane</id> </SOAP-ENV:Body> </SOAP-ENV:Envelope>
SOAP 1.2 encoding is cleaner and produces more accurate XML encodings of data graphs by setting the id attribute on the element that is referenced:
<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://www.w3.org/2003/05/soap-envelope" xmlns:SOAP-ENC="http://www.w3.org/2003/05/soap-encoding" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlsn:ns="urn:DB"> <SOAP-ENV:Body> <ns:DBupdate SOAP-ENV:encodingStyle="http://www.w3.org/2003/05/soap-encoding"> <records SOAP-ENC:itemType="ns:record" SOAP-ENC:arraySize="3"> <item> <name SOAP-ENC:id="_1">Joe</name> <SSN>1234567890</SSN> </item> <item> <name>Jane</name> <SSN>1987654320</SSN> </item> <item> <name SOAP-ENC:ref="_1"/> <SSN>2345678901</SSN> </item> </records> </ns:DBupdate> </SOAP-ENV:Body> </SOAP-ENV:Envelope>
NoteSome SOAP 1.2 applications consider the namespace
SOAP-ENCof
SOAP-ENC:idand
SOAP-ENC:refoptional.
The gSOAP SOAP 1.2 encoding serialization follows the 2007 standard, while accepting unqualified id and ref attributes.
To remove all rendered id-ref multi-referenced elements in gSOAP, use the
SOAP_XML_TREEflag
to initialize the gSOAP engine context.
Some XML validation rules are turned off with SOAP encoding, because of the presence of additional attributes, such as id and ref/href, SOAP arrays with arbitrary element tags for array elements, and the occurrence of additional multi-ref elements in the
SOAP 1.1 Body.
The use of "literal" puts no restrictions on the XML in the SOAP Body. Full XML validation is possible, which can be enabled with the
SOAP_XML_STRICTflag
to initialize the gSOAP engine context. However, data graphs will be serialized as trees and cycles in the data will be cut from the XML rendition.
SOAP 1.1 versus SOAP 1.2
There are two SOAP protocol versions: 1.1 and 1.2. The gSOAP tools can switch between the two versions seamlessly. You can declare the default SOAP version for a service operation as follows://gsoap ns service method-protocol: DBupdate SOAP1.2
The gSOAP soapcpp2 auto-generates client and server code. At the client side, this operation sends data with SOAP 1.2 but accepts responses also in SOAP 1.1. At the server side, this operation accepts requests in SOAP 1.1 and 1.2 and will return responses
in the same SOAP version.
As we discussed in the previous section, the SOAP 1.2 protocol has a cleaner multi-referenced element serialization format that greatly enhances the accuracy of data graph serialization with SOAP RPC encoding and is therefore recommended.
The SOAP 1.2 protocol default can also be set by importing and loading
gsoap/import/soap12.h:
#import "soap12.h"
Non-SOAP XML serialization
You can serialize data that is stored on the heap, on the stack (locals), and static data as long as the serializable (i.e. non-transient) members are properly initialized and pointers in the structures are either NULL or point to valid structures. Deserializeddata is put on the heap and managed by the gSOAP engine context
struct soap, see also memory management.
You can read and write XML directly to a file or stream with the serializing operations on classes and structs.
To define and use XML Web service client and service operations, we can declare these operations in your gSOAP header file with the data binding interface for soapcpp2 as functions. The function are translated by soapcpp2 to client-side service invocation
calls and server-side service operation dispatchers.
The REST operations POST, GET, and PUT are declared with
//gsoapdirectives
in the gSOAP header file for soapcpp2. For example, a REST POST operation is declared as follows:
//gsoap ns service namespace: urn:DB
//gsoap ns service method-protocol: DBupdate POSTint ns__DBupdate(...);
There is no SOAP Envelope and no SOAP Body in the payload for
DBupdate.
Also the XML serialization rules are identical to SOAP document/literal. The XML payload only has the operation name as an element with its parameters serialized as subelements:
<ns:DBupdate xmln:ns="urn:DB" ...> ... </ns:DBupdate>
To force id-ref serialization with REST similar to SOAP 1.2 multi-reference encoding, use the
SOAP_XML_GRAPHflag
to initialize the gSOAP engine context. The XML serialization includes id and ref attributes for multi-referenced elements as follows:
<ns:DBupdate xmln:ns="urn:DB" ...> <records> <item> <name id="_1">Joe</name> <SSN>1234567890</SSN> </item> <item> <name>Jane</name> <SSN>1987654320</SSN> </item> <item> <name ref="_1"/> <SSN>2345678901</SSN> </item> </records> </ns:DBupdate>
Input and output
Reading and writing XML from/to files, streams and string buffers is done via the managing context by setting one of the following context members that control IO sources and sinks:soap->recvfd = fd;
// an int file descriptor to read from (0 by default)
soap->sendfd = fd;
// an int file descriptor to write to (1 by default)
soap->is = &is;
// C++ only: a std::istream is object to read from
soap->os = &os;
// C++ only: a std::ostream os object to write to
soap->is = cs;
// C only: a const char* string to read from (soap->is will advance)
soap->os = &cs;
// C only: pointer to a const char*, will be set to point to the string output
Normally, all of these context members are NULL, which is required to send and receive data over sockets by gSOAP clients and servers. Therefore, if you set any of these context members in a client or server application then you MUST reset them to NULL to
ensure that socket communications are not blocked.
Note: the use of
soap->isand
soap->osin
C requires gSOAP 2.8.28 or later.
In the following sections, we present more details on how to read and write to files and streams, and use string buffers as sources and sinks for XML data.
In addition, you can set IO callback functions to handle IO at a lower level.
For more details, see the gSOAP user guide.
Reading and writing from/to files and streams
The default IO is standard input and output. Other sources and sinks (those listed above) will be used until you (re)set them. For example with file-based input and output:FILE *fp = fopen("record.xml",
"r");
if (fp != NULL)
{
soap->recvfd = fileno(fp);
// get file descriptor of file to read from
if (soap_read_ns__record(soap, &pers1))
... // handle IO error
fclose(fp);
soap->recvfd = 0;
// read from stdin, or -1 to block reading
}
FILE *fp = fopen("record.xml",
"w");
if (fp != NULL)
{
soap->sendfd = fileno(fp);
// get file descriptor of file to write to
if (soap_write_ns__record(soap, &pers1))
... // handle IO error
fclose(fp);
soap->sendfd = 1;
// write to stdout, or -1 to block writing
}
Similar code with streams in C++:
#include <fstream>
std::fstream fs;
fs.open("record.xml", std::ios::in);
if (fs)
{
soap->is = &fs;
if (soap_read__ns__record(soap, &pers1))
... // handle IO error
fs.close();
soap->is = NULL;
}
fs.open("record.xml", std::ios::out);
if (fs)
{
soap->os = &fs;
if (soap_write__ns__record(soap, &pers1))
... // handle IO error
fs.close();
soap->os = NULL;
}
Reading and writing from/to string buffers
For C++ we recommend to usestd::stringstreamobjects
from
<sstream>as illustrated in the
following example:
#include <sstream>
std::stringstream ss;
ss.str("...");
// XML to parse
soap->is = &ss;
if (soap_read__ns__record(soap, &pers1))
... // handle IO error
soap->is = NULL;
soap->os = &ss;
if (soap_write__ns__record(soap, &pers1))
... // handle IO error
soap->os = NULL;
std::string s = ss.str();
// string with XML
For C we can use
soap->isand
soap->osto
point to strings of XML content as follows (this requires gSOAP 2.8.28 or later):
soap->is =
"..."; // XML to parse
if (soap_read__ns__record(soap, &pers1))
... // handle IO error
soap->is = NULL;
const
char *cs = NULL;
soap->os = &cs;
if (soap_write__ns__record(soap, &pers1))
... // handle IO error
soap->os = NULL;
... = cs;
// string with XML (do not free(cs): managed by the context and freed with soap_end())
Note that
soap->osis a pointer to
a
const char*string. The pointer is
set by the managing context to point to the XML data that is stored on the context-managed heap.
For earlier gSOAP versions we recommend to use IO callbacks
soap->frecvand
soap->fsend,
see the gSOAP user guide.
Memory management
Memory management with thesoapcontext
enables us to allocate data in context-managed heap space that can be collectively deleted. All deserialized data is placed on the context-managed heap by the gSOAP engine.
Memory management in C
In C (wsdl2h option-cand soapcpp2
option
-c), the gSOAP engine allocates
data on a context-managed heap with:
void *soap_malloc(struct soap*, size_t len).
You can also make shallow copies of data with
soap_memdupthat
uses
soap_mallocand a safe version
of
memcpyto copy a chunk of data
srcwith
length
lento the context-managed heap:
void *soap_memdup(struct soap*, const void *src, size_t len)
This function returns a pointer to the copy. This function requires gSOAP 2.8.27 or later.
The
soap_mallocfunction is a wrapper
around
malloc, but which also permits
the
struct soapcontext to track all
heap allocations for collective deletion with
soap_end(soap):
#include "soapH.h"
#include "ns.nsmap"
...
struct soap *soap = soap_new();
// new context
...
struct ns__record *record = soap_malloc(soap,
sizeof(struct ns__record));
soap_default_ns__record(soap, record);
// auto-generated struct initializer
...
soap_destroy(soap);
// only for C++, see section on C++ below
soap_end(soap);
// delete record and all other heap allocations
soap_free(soap);
// delete context
The soapcpp2 auto-generated deserializers in C use
soap_mallocto
allocate and populate deserialized structures, which are managed by the context for collective deletion.
To make
char*and
wchar_t*string
copies to the context-managed heap, we can use the functions:
char *soap_strdup(struct soap*, const char*str)and
wchar_t *soap_wstrdup(struct soap*, const wchar_t *wstr).
If your C compiler supports
typeofthen
you can use the following macro to simplify the managed heap allocation and initialization of primitive values:
#define soap_assign(soap, lhs, rhs) (*(lhs = (typeof(lhs))soap_malloc(soap, sizeof(*lhs))) = rhs)
Pointers to primitive values are often used for optional members. For example, assume we have the following struct:
struct
ns__record
{
const
char *name;
// required name
uint64_t *SSN;
// optional SSN
struct
ns__record *spouse; // optional spouse
};
Use
soap_assignto create a SSN value
on the managed heap:
struct soap *soap = soap_new();
// new context
...
struct ns__record *record = soap_malloc(soap,
sizeof(struct ns__record));
soap_default_ns__record(soap, record);
record->name = soap_strdup(soap,
"Joe");
soap_assign(soap, record->SSN, 1234567890LL);
...
soap_end(soap);
// delete managed soap_malloc'ed heap data
soap_free(soap);
// delete context
Without the
soap_assignmacro, you
will need two lines of code, one to allocate and one to assign (you should also use this if your system can run out of memory):
assert((record->SSN = (uint64_t*)soap_malloc(soap,
sizeof(utint64_t))) != NULL);
*record->SSN = 1234567890LL;
The gSOAP serializer can serialize any heap, stack, or static allocated data. So we can also create a new record as follows:
struct soap *soap = soap_new();
// new context
...
struct ns__record *record = soap_malloc(soap,
sizeof(struct ns__record));
static uint64_t SSN = 1234567890LL;
soap_default_ns__record(soap, record);
record->name =
"Joe";
record->SSN = &SSN;
// safe to use static values: the value of record->SSN is never changed by gSOAP
...
soap_end(soap);
// delete managed soap_malloc'ed heap data
soap_free(soap);
// delete context
Use the soapcpp2 auto-generated
soap_dup_Tfunctions
to duplicate data into another context (this requires soapcpp2 option
-Ecto
generate), here shown for C with the second argument
dstNULL
because we want to allocate a new managed structure:
struct soap *other_soap = soap_new();
// another context
struct
ns__record *other_record = soap_dup_ns__record(other_soap, NULL, record);
...
soap_destroy(other_soap);
// only for C++, see section on C++ below
soap_end(other_soap);
// delete other_record and all of its deep data
soap_free(other_soap);
// delete context
Note that the only reason to use another context and not to use the primary context is when the primary context must be destroyed together with all of the objects it manages while some of the objects must be kept alive. If the objects that are kept alive
contain deep cycles then this is the only option we have, because deep copy with a managing context detects and preserves these cycles unless the
SOAP_XML_TREEflag
is used with the context:
struct soap *other_soap = soap_new1(SOAP_XML_TREE);
// another context
struct
ns__record *other_record = soap_dup_ns__record(other_soap, NULL, record);
The resulting deep copy will be a full copy of the source data structure as a tree without co-referenced data (i.e. no digraph) and without cycles. Cycles are pruned and (one of the) pointers that forms a cycle is repaced by NULL.
You can also deep copy into unmanaged space and use the auto-generated
soap_del_T()function
(requires soapcpp2 option
-Edto generate)
to delete it later, but you MUST NOT do this for any data that has deep cycles in its runtime data structure:
struct
ns__record *other_record = soap_dup_ns__record(NULL, NULL, record);
...
soap_del_ns__record(other_record);
// deep delete record data members
free(other_record);
// delete the record
Cycles in the data structure will lead to non-termination when making unmanaged deep copies. Consider for example:
struct
ns__record
{
const
char *name;
// required name
uint64_t SSN;
// required SSN
struct
ns__record *spouse; // optional spouse
};
The code to populate a structure with a mutual spouse relationship:
struct soap *soap = soap_new();
...
struct ns__record pers1, pers2;
soap_default_ns__record(soap, &pers1);
soap_default_ns__record(soap, &pers2);
pers1.name =
"Joe"; // OK to serialize static data
pers1.SSN = 1234567890;
pers1.spouse = &pers2;
pers2.name = soap_strdup(soap,
"Jane"); // allocates and copies a string
pers2.SSN = 1987654320;
pers2.spouse = &pers1;
...
struct ns__record *pers3 = soap_dup_ns__record(NULL, NULL, &pers1);
// BAD
struct
ns__record *pers4 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
soap_set_mode(soap, SOAP_XML_TREE);
struct
ns__record *pers5 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
As we can see, the gSOAP serializer can serialize any heap, stack, or static allocated data, such as in the code above. So we can serialize the stack-allocated
pers1record
as follows:
FILE *fp = fopen("record.xml",
"w");
if (fp != NULL)
{
soap->sendfd = fileno(fp);
// file descriptor to write to
soap_set_mode(soap, SOAP_XML_GRAPH);
// support id-ref w/o requiring SOAP
soap_clr_mode(soap, SOAP_XML_TREE);
// if set, clear
soap_write_ns__record(soap, &pers1);
fclose(fp);
soap->sendfd = -1;
// block further writing
}
which produces an XML document record.xml that is similar to:
<ns:record xmlns:ns="urn:types" id="Joe"> <name>Joe</name> <SSN>1234567890</SSN> <spouse id="Jane"> <name>Jane</name> <SSN>1987654320</SSN> <spouse ref="#Joe"/> </spouse> </ns:record>
Deserialization of an XML document with a SOAP 1.1/1.2 encoded id-ref graph leads to the same non-termination problem when we later try to copy the data into unmanaged space:
struct soap *soap = soap_new1(SOAP_XML_GRAPH);
// support id-ref w/o SOAP
...
struct ns__record pers1;
FILE *fp = fopen("record.xml",
"r");
if (fp != NULL)
{
soap->recvfd = fileno(fp);
if (soap_read_ns__record(soap, &pers1))
... // handle IO error
fclose(fp);
soap->recvfd = -1;
// blocks further reading
}
...
struct ns__record *pers3 = soap_dup_ns__record(NULL, NULL, &pers1);
// BAD
struct
ns__record *pers4 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
soap_set_mode(soap, SOAP_XML_TREE);
struct
ns__record *pers5 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
Copying data with
soap_dup_T(soap)into
managed space is always safe. Copying into unmanaged space requires diligence. But deleting unmanaged data is easy with
soap_del_T().
You can also use
soap_del_T()to
delete structures that you created in C, but only if these structures are created with
mallocand
do NOT contain pointers to stack and static data.
Memory management in C++
In C++, the gSOAP engine allocates data on a managed heap using a combination ofvoid *soap_malloc(struct soap*, size_t len)and
soap_new_T(),
where
Tis the name of a class, struct,
or class template (container or smart pointer). Heap allocation is tracked by the
struct soapcontext for collective deletion with
soap_destroy(soap)and
soap_end(soap).
Only structs, classes, and class templates are allocated with
newvia
soap_new_T(struct soap*)and mass-deleted with
soap_destroy(soap).
There are four variations of
soap_new_Tfor
class/struct/template type
Tthat soapcpp2
auto-generates to create instances on a context-managed heap:
T * soap_new_T(struct soap*)returns
a new instance of
Twith default data
member initializations that are set with the soapcpp2 auto-generated
void T::soap_default(struct soap*)method), but ONLY IF the soapcpp2 auto-generated default constructor is used that invokes
soap_default()and
was not replaced by a user-defined default constructor.
T * soap_new_T(struct soap*, int n)returns
an array of
nnew instances of
T.
Similar to the above, instances are initialized.
T * soap_new_req_T(struct soap*, ...)returns
a new instance of
Tand sets the required
data members to the values specified in
....
The required data members are those with nonzero minOccurs, see the subsections on (smart) pointer members and their
occurrence constraints and container members and their occurrence constraints.
T * soap_new_set_T(struct soap*, ...)returns
a new instance of
Tand sets the public/serializable
data members to the values specified in
....
The above functions can be invoked with a NULL
soapcontext,
but you are responsible to use
delete Tto
remove this instance from the unmanaged heap.
For example, to allocate a managed
std::stringyou
can use:
std::string *s =
soap_new_std__string(soap);
Primitive types and arrays of these are allocated with
soap_mallocby
the gSOAP engine. As we stated above, all types except for classes, structs, class templates (containers and smart pointers) are allocated with
soap_mallocfor
reasons of efficiency.
You can use a C++ template to simplify the managed allocation and initialization of primitive values as follows (this is for primitive types only, because structs and classes are allocated with
soap_new_T):
template<class T>
T * soap_make(struct soap *soap, T val)
{
T *p = (T*)soap_malloc(soap,
sizeof(T));
if (p)
// out of memory? Can also guard with assert(p != NULL) or throw an error
*p = val;
return p;
}
For example, assuming we have the following class:
class
ns__record
{
public:
std::string name;
// required name
uint64_t *SSN;
// optional SSN
ns__record *spouse;
// optional spouse
};
You can instantiate a record by using the auto-generated
soap_new_set_ns__recordand
use
soap_maketo create a SSN value
on the managed heap:
soap *soap = soap_new();
// new context
...
ns__record *record = soap_new_set_ns__record(
soap,
"Joe",
soap_make<uint64_t>(soap, 1234567890LL),
NULL);
...
soap_destroy(soap);
// delete record and all other managed instances
soap_end(soap);
// delete managed soap_malloc'ed heap data
soap_free(soap);
// delete context
Note however that the gSOAP serializer can serialize any heap, stack, or static allocated data. So we can also create a new record as follows:
uint64_t SSN = 1234567890LL;
ns__record *record = soap_new_set_ns__record(soap,
"Joe", &SSN, NULL);
which will be fine to serialize this record as long as the local
SSNstack-allocated
value remains in scope when invoking the serializer and/or using
record.
It does not matter if
soap_destroyand
soap_endare
called beyond the scope of
SSN.
To facilitate class methods to access the managing context, we can add a soap context pointer to a class/struct:
class
ns__record
{
...
void create_more();
// needs a context to create more internal data
protected:
struct soap *soap; // the context that manages this instance, or NULL
};
The context is set when invoking
soap_new_T(and
similar) with a non-NULL context argument.
Use the soapcpp2 auto-generated
soap_dup_Tfunctions
to duplicate data into another context (this requires soapcpp2 option
-Ecto
generate), here shown for C++ with the second argument
dstNULL
to allocate a new managed object:
soap *other_soap = soap_new();
// another context
ns__record *other_record = soap_dup_ns__record(other_soap, NULL, record);
...
soap_destroy(other_soap);
// delete record and other managed instances
soap_end(other_soap);
// delete other data (the SSNs on the heap)
soap_free(other_soap);
// delete context
To duplicate base and derived instances when a base class pointer or reference is provided, use the auto-generated method
T* T::soap_dup(struct soap*):
soap *other_soap = soap_new();
// another context
ns__record *other_record = record->soap_dup(other_soap);
...
soap_destroy(other_soap);
// delete record and other managed instances
soap_end(other_soap);
// delete other data (the SSNs on the heap)
soap_free(other_soap);
// delete context
Note that the only reason to use another context and not to use the primary context is when the primary context must be destroyed together with all of the objects it manages while some of the objects must be kept alive. If the objects that are kept alive
contain deep cycles then this is the only option we have, because deep copy with a managing context detects and preserves these cycles unless the
SOAP_XML_TREEflag
is used with the context:
soap *other_soap = soap_new1(SOAP_XML_TREE);
// another context
ns__record *other_record = record->soap_dup(other_soap);
// deep tree copy
The resulting deep copy will be a full copy of the source data structure as a tree without co-referenced data (i.e. no digraph) and without cycles. Cycles are pruned and (one of the) pointers that forms a cycle is repaced by NULL.
You can also deep copy into unmanaged space and use the auto-generated
soap_del_T()function
or the
T::soap_del()method (requires
soapcpp2 option
-Edto generate) to
delete it later, but we MUST NOT do this for any data that has deep cycles in its runtime data structure graph:
ns__record *other_record = record->soap_dup(NULL);
...
other_record->soap_del();
// deep delete record data members
delete other_record;
// delete the record
Cycles in the data structure will lead to non-termination when making unmanaged deep copies. Consider for example:
class
ns__record
{
const
char *name;
// required name
uint64_t SSN;
// required SSN
ns__record *spouse;
// optional spouse
};
The code to populate a structure with a mutual spouse relationship:
soap *soap = soap_new();
...
ns__record pers1, pers2;
pers1.name =
"Joe";
pers1.SSN = 1234567890;
pers1.spouse = &pers2;
pers2.name =
"Jane";
pers2.SSN = 1987654320;
pers2.spouse = &pers1;
...
ns__record *pers3 = soap_dup_ns__record(NULL, NULL, &pers1);
// BAD
ns__record *pers4 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
soap_set_mode(soap, SOAP_XML_TREE);
ns__record *pers5 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
Note that the gSOAP serializer can serialize any heap, stack, or static allocated data, such as in the code above. So we can serialize the stack-allocated
pers1record
as follows:
FILE *fp = fopen("record.xml",
"w");
if (fp != NULL)
{
soap->sendfd = fileno(fp);
// file descriptor to write to
soap_set_mode(soap, SOAP_XML_GRAPH);
// support id-ref w/o requiring SOAP
soap_clr_mode(soap, SOAP_XML_TREE);
// if set, clear
if (soap_write_ns__record(soap, &pers1))
... // handle IO error
fclose(fp);
soap->sendfd = -1;
// block further writing
}
which produces an XML document record.xml that is similar to:
<ns:record xmlns:ns="urn:types" id="Joe"> <name>Joe</name> <SSN>1234567890</SSN> <spouse id="Jane"> <name>Jane</name> <SSN>1987654320</SSN> <spouse ref="#Joe"/> </spouse> </ns:record>
Deserialization of an XML document with a SOAP 1.1/1.2 encoded id-ref graph leads to the same non-termination problem when we later try to copy the data into unmanaged space:
soap *soap = soap_new1(SOAP_XML_GRAPH);
// support id-ref w/o SOAP
...
ns__record pers1;
FILE *fp = fopen("record.xml",
"r");
if (fp != NULL)
{
soap->recvfd = fileno(fp);
// file descriptor to read from
if (soap_read_ns__record(soap, &pers1))
... // handle IO error
fclose(fp);
soap->recvfd = -1;
// block further reading
}
...
ns__record *pers3 = soap_dup_ns__record(NULL, NULL, &pers1);
// BAD
ns__record *pers4 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
soap_set_mode(soap, SOAP_XML_TREE);
ns__record *pers5 = soap_dup_ns__record(soap, NULL, &pers1);
// OK
Copying data with
soap_dup_T(soap)into
managed space is always safe. Copying into unmanaged space requires diligence. But deleting unmanaged data is easy with
soap_del_T().
You can also use
soap_del_T()to
delete structures in C++, but only if these structures are created with
new(and
new []for arrays when applicable) for classes, structs, and class templates and with
mallocfor
anything else, and the structures do NOT contain pointers to stack and static data.
Context flags to initialize the soap struct
There are several context initialization flags and context mode flags to control XML serialization at runtime. The flags are set withsoap_new1()for
heap allocation of contexts:
struct soap *soap = soap_new1(<flag> | <flag> ... | <flag>);
,,,
soap_destroy(soap);
// delete objects
soap_end(soap);
// delete other data and temp data
soap_free(soap);
// free context
and with
soap_init1()with stack
allocated contexts:
struct soap soap;
soap_init1(&soap, <flag> | <flag> ... | <flag>);
,,,
soap_destroy(&soap);
// delete objects
soap_end(&soap);
// delete other data and temp data
soap_done(&soap);
// clear context
where
<flag>is one of:
SOAP_C_UTFSTRING: enables all
std::stringand
char*strings
to contain UTF-8 content. This option is recommended.
SOAP_C_NILSTRING: treat empty strings
as if they were NULL pointers, i.e. omits elements and attributes when empty.
SOAP_XML_STRICT: strictly validates
XML while deserializing. Should not be used together with SOAP 1.1/1.2 encoding style of messaging. Use soapcpp2 option
-sto
hard code
SOAP_XML_STRICTin the generated
serializers. Not recommended with SOAP 1.1/1.2 encoding style messaging.
SOAP_XML_INDENT: produces indented
XML.
SOAP_XML_CANONICAL: c14n canonocalization,
removes unused
xmlnsbindings and adds
them to appropriate places by applying c14n normalization rules. Should not be used together with SOAP 1.1/1.2 encoding style messaging.
SOAP_XML_TREE: write tree XML without
id-ref, while pruning data structure cycles to prevent nontermination of the serializer for cyclic structures.
SOAP_XML_GRAPH: write graph (digraph
and cyclic graphs with shared pointers to objects) using id-ref attributes. That is, XML with SOAP multi-ref encoded id-ref elements. This is a structure-preserving serialization format, because co-referenced data and also cyclic relations are accurately represented.
SOAP_XML_DEFAULTNS: uses xmlns default
namespace declarations, assuming that the schema attribute form is "qualified" by default (be warned if it is not, since attributes in the null namespace will get bound to namespaces!).
SOAP_XML_NIL: emit empty element
with
xsi:nilfor all NULL pointers
serialized.
SOAP_XML_IGNORENS: the XML parser
ignores XML namespaces, i.e. element and attribute tag names match independent of their namespace.
SOAP_XML_NOTYPE: removes all
xsi:typeattribuation.
This option is usually not needed unless the receiver rejects all
xsi:typeattributes.
This option may affect the quality of the deserializer, which relies on
xsi:typeattributes
to distinguish base class instances from derived class instances transported in the XML payloads.
SOAP_IO_CHUNK: to enable HTTP chunked
transfers.
SOAP_IO_STORE: full buffering of
outbound messages.
SOAP_ENC_ZLIB: compress messages,
requires compiling with
-DWITH_GZIPand
linking with zlib (
-lz).
SOAP_ENC_MIME: enable MIME attachments,
see MIME/MTOM attachment binary types.
SOAP_ENC_MTOM: enable MTOM attachments,
see MIME/MTOM attachment binary types.
Features and limitations
In general, to use the generated code:Make sure to
#include "soapH.h"in
your code and also define a namespace table or
#include "ns.nsmap"with the generated table, where
nsis
the namespace prefix for services.
Use soapcpp2 option -j (C++ only) to generate C++ proxy and service objects. The auto-generated files include documented inferfaces. Compile with soapC.cpp and link with -lgsoap++, or alternatively compile stdsoap2.cpp.
Without soapcpp2 option -j: client-side uses the auto-generated soapClient.cpp and soapC.cpp (or C versions of those). Compile and link with -lgsoap++ (-lgsoap for C), or alternatively compile stdsoap2.cpp (stdsoap2.c for C).
Without soapcpp2 option -j: server-side uses the auto-generated soapServer.cpp and soapC.cpp (or C versions of those). Compile and link with -lgsoap++ (-lgsoap for C), or alternatively compile stdsoap2.cpp (stdsoap2.c for C).
Use
soap_new()or
soap_new1(int flags)to allocate and initialize a heap-allocated context with or without flags. Delete this context with
soap_free(struct soap*), but only after
soap_destroy(struct soap*)and
soap_end(struct soap*).
Use
soap_init(struct *soap)or
soap_init1(struct soap*, int flags)to initialize a stack-allocated context with or without flags. End the use of this context with
soap_done(struct soap*), but only after
soap_destroy(struct soap*)and
soap_end(struct soap*).
Additional notes with respect to the wsdl2h and soapcpp2 tools:
Nested classes, structs, and unions in a gSOAP header file are unnested by soapcpp2.
Use
#import "file.h"instead of
#includeto
import other header files in a gSOAP header file for soapcpp2. The
#include,
#define,
and
#pragmaare accepted by soapcpp2,
but are moved to the very start of the generated code for the C/C++ compiler to include before all generated definitions. Often it is useful to add an
#includewith
a volatile type that includes the actual type declaration, and to ensure transient types are declared when these
are used in a data binding interface declared in a gSOAP header file for soapcpp2.
To remove any SOAP-specific bindings, use soapcpp2 option
-0.
A gSOAP header file for soapcpp2 should not include any code statements, only data type declarations. This includes constructor initialization lists that are not permitted. Use member initializations instead.
C++ namespaces are supported. Use wsdl2h option
-qname.
Or add a
namespace name { ... } tothe header file, but the
{ ... } MUSTcover the entire header file content from begin to end.Optional XML DOM support can be used to store mixed content or literal XML content. Otherwise, mixed content may be lost. Use wsdl2h option
-dfor
XML DOM support and compile and link with
dom.cor
dom.cpp.
For details, see XML DOM and XPath.
Removing SOAP namespaces from XML payloads
The soapcpp2 tool generates a.nsmapfile
that includes two bindings for SOAP namespaces. We can remove all SOAP namespaces (and SOAP processing logic) with soapcpp2 option
-0or
by simply setting the two entries to NULL:
struct
Namespace namespaces[] =
{
{"SOAP-ENV", NULL, NULL, NULL},
{"SOAP-ENC", NULL, NULL, NULL},
...
};
Note that once the
.nsmapis generated,
you can copy-paste the content into your project code. However, if we rerun wsdl2h on updated WSDL/XSD files or
typemap.datdeclarations
then we need to use the updated table.
In cases that no XML namespaces are used at all, for example with XML-RPC, you may use an empty namespace table:
struct
Namespace namespaces[] = {{NULL,NULL,NULL,NULL}};
However, beware that any built-in xsi attributes that are rendered will lack the proper namespace binding. At least we suggest to use
SOAP_XML_NOTYPEfor
this reason.
Examples
Select the project files below to peruse the source code examples.Source files
address.xsdAddress book schema
address.cppAddress
book app (reads/writes address.xml file)
addresstypemap.datSchema namespace
prefix name preference for wsdl2h
graph.hGraph data
binding (tree, digraph, cyclic graph)
graph.cppTest
graph serialization as tree, digraph, and cyclic
Generated files
address.hgSOAP-specific
data binding definitions from address.xsd
addressStub.hC++
data binding definitions
addressH.hSerializers
addressC.cppSerializers
address.xmlAddress book data generated
by address app
graphStub.hC++
data binding definitions
graphH.hSerializers
graphC.cppSerializers
g.xsdXSD schema with
g:GraphcomplexType
g.nsmapxmlns bindings namespace
mapping table
Build steps
Building the AddressBook example:wsdl2h -g -t addresstypemap.dat address.xsd soapcpp2 -0 -CS -I../../import -p address address.h c++ -I../.. address.cpp addressC.cpp -o address -lgsoap++
Option
-gproduces bindings for global
(root) elements in addition to types. In this case the root element
a:address-bookis
bound to
_a__address_book.
The complexType
a:addressis bound
to class
a__address,
which is also the type of
_a__address_book.
This option is not required, but allows you to use global element tag names when referring to their serializers, instead of their type name. Option
-0removes
the SOAP protocol. Options
-Cand
-Sremoves
client and server code generation. Option
-prenames
the output
soapfiles to
addressfiles.
See the
address.cppimplementation
and related pages.
The
addresstypemap.datfile specifies
the XML namespace prefix for the bindings:
# Bind the address book schema namespace to prefix 'a' a = "urn:address-book-example" # By default the xsd:dateTime schema type is translated to time_t # To map xsd:dateTime to struct tm, enable the following line: # xsd__dateTime = #import "../../custom/struct_tm.h" # ... and compile/link with custom/struct_tm.c
The DOB field is a
xsd:dateTime,
which is bound to
time_tby default.
To change this to
struct tm, enable
the import of the
xsd__dateTimecustom
serializer by uncommenting the definition of
xsd__dateTimein
addresstypemap.dat.
Then change
soap_dateTime2sto
soap_xsd__dateTime2sin
the code.
Building the graph serialization example:
soapcpp2 -CS -I../../import -p graph graph.h c++ -I../.. graph.cpp graphC.cpp -o graph -lgsoap++
To compile without using the
libgsoap++library:
simply compile
stdsoap2.cpptogether
with the above.
Usage
To execute the AddressBook example:./address
To execute the Graph serialization example:
./graph
Copyright (C) 2016, Robert van Engelen, Genivia Inc., All Rights Reserved.
Converted on Wed Mar 2 2016 10:24:54 by Doxygen 1.8.10
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