nginx中Location的匹配优先规则

This directive allows different configurations depending on the URI. It can be configured using both conventional strings and regular expressions. To use regular expressions, you must use the prefix ~* for case insensitive match and ~ for case sensitive match.

To determine which location directive matches a particular query, the conventional strings are checked first. Conventional strings match the beginning portion of the query and are case-sensitive - the most specific match will be used (see below on how nginx determines this). Afterwards, regular expressions are checked in the order defined in the configuration file. The first regular expression to match the query will stop the search. If no regular expression matches are found, the result from the convention string search is used.

There are two ways to modify this behavior. The first is to use the prefix "=", which matches an exact query only. If the query matches, then searching stops and the request is handled immediately. For example, if the request "/" occurs frequently, then using "location = /" will expedite the processing of this request.

The second is to use the prefix ^~. This prefix is used with a conventional string and tells nginx to not check regular expressions if the path provided is a match. For instance, "location ^~ /images/" would halt searching if the query begins with /images/ - all regular expression directives would not be checked.

Furthermore it is important to know that NGINX does the comparison not URL encoded, so if you have a URL like "/images/%20/test" then use "/images/ /test" to determine the location.

To summarize, the order in which directives are checked is as follows:

1. Directives with the = prefix that match the query exactly. If found, searching stops.
2. All remaining directives with conventional strings, longest match first. If this match used the ^~ prefix, searching stops.
3. Regular expressions, in order of definition in the configuration file.
4. If #3 yielded a match, that result is used. Else the match from #2 is used.