Elasticsearch.Net使用(一)【入门篇】

首先去官网下载Elasticsearch 2.3.4安装包,解压后，在cmd命令行进入安装目录，再进入 bin目录，运行elasticsearch.bat命令

elasticsearch插件elasticsearch-head安装：

bin目录下执行命令plugin -install mobz/elasticsearch-head

然后开始.net编程,构建控制台应用程序

Program.cs代码如下:

class Program
{
static void Main(string[] args)
{
Console.WriteLine("*Program 开始运行 : "  + DateTime.Now);
var business = new Business();

var swRead = new Stopwatch();
//swRead.Start();
//business.AddToDb();//sqlserver数据库增加数据
//swRead.Stop();
//Console.WriteLine("DB 写入时间  : " + swRead.ElapsedMilliseconds);

//swRead.Reset();
//swRead.Start();
//business.AddToElasticIndex();
//swRead.Stop();
//Console.WriteLine("ES 写入时间  : " + swRead.ElapsedMilliseconds);

var sw = new Stopwatch();
sw.Start();
var personsFromDB = business.GetFromDB();
sw.Stop();
Console.WriteLine("DB 读时间  : " + sw.ElapsedMilliseconds);

sw.Reset();
sw.Start();
var personsFromEs = business.GetFromES();
sw.Stop();
Console.WriteLine("ES 读时间  : " + sw.ElapsedMilliseconds);

Console.ReadLine();
}
}

BLL层的Business.cs类:

public class Business
{
private List<PersonDetail> _personList = new List<PersonDetail>();

//SQLSERVER数据库
PersonDbProvider dbProvider = new PersonDbProvider();

//ElasticSearch
ESProvider esProvider = new ESProvider();

public void AddToDb()
{
_personList = Util.Get10000PersonDetails();//辅助类,生成10000条数据

foreach (var personDetail in _personList)
{
dbProvider.AddPerson(personDetail);
}
}

public void AddToElasticIndex()
{
_personList = Util.Get10000PersonDetailsWithID();
foreach (var personDetail in _personList)
{
esProvider.Index(personDetail);
}
}

public List<PersonDetail> GetFromDB()
{
return dbProvider.GetAllPersonDetails();
}

public List<PersonDetail> GetFromES()
{
return esProvider.GetAll();
}

}

PersonDbProvider.cs和ElasticSearchProvider.cs以及Util.cs,Setting.cs类:

public class PersonDbProvider
{
public bool AddPerson(PersonDetail personDetail)
{
try
{   //数据库上下文
using (var db = new PersonContext())
{
db.PersonDetails.Add(personDetail);
db.SaveChanges();
return true;
}
}
catch (Exception)
{
return false;
}
}

public List<PersonDetail> GetAllPersonDetails()
{
try
{
using (var db = new PersonContext())
{
return db.PersonDetails.ToList();
}
}
catch (Exception)
{
return null;
}
}
}

public class ESProvider
{
public static ElasticClient client = new ElasticClient(Setting.ConnectionSettings);

public bool Index(PersonDetail person)
{
var client = new ElasticClient(Setting.ConnectionSettings);
try
{
//添加数据
//在调用下面的index方法的时候，如果没有指定使用哪个index，ElasticSearch会直接使用我们在setting中的defaultIndex，如果没有，则会自动创建
var index = client.Index(person);
return index.Created;
}
catch (Exception ex)
{
Console.WriteLine(" Excepton Message : " + ex.Message);
}
return false;
}

public List<PersonDetail> GetAll()
{
var searchResults = client.Search<PersonDetail>(s => s
.From(0)
.Size(10000)
);
return searchResults.Documents.ToList();
}

public List<PersonDetail> GetEntities(string keyword)
{
var client = new ElasticClient(Setting.ConnectionSettings);

#region 全文搜索

keyword = String.Format("*{0}*", keyword);
//默认的Operator是Or,当keyword是类似于"One Two"之类的中间有空格的时候，会被当成两个关键词搜索，然后搜索结果进行or运算
//所以我们需要根据需求来调整Operator
var searchResults = client.Search<PersonDetail>(s => s
.Index("elastic-search-app")
.Query(q => q.QueryString(qs => qs.Query(keyword).DefaultOperator(Operator.And)))
);

//--------------------------------------------------------------------------------------
//另外由于ES是分词搜索，所以当我们要用"One"来搜索完整的单词"JustOne"的时候，就必须在"One"外面添加**，类似于SQL里面的%keyword%，但是这样的做法会导致在用完整的单词来搜索的时候搜索不到结果，所以我们需要使用下面的方式

//wholeKeyword = keyword;
//keyword = String.Format("*{0}*", keyword);
//QueryContainer query = new QueryStringQuery() { Query = keyword, DefaultOperator = Operator.And };
//if (!String.IsNullOrEmpty(wholeKeyword))
//{
//    QueryContainer wholeWordQuery = new QueryStringQuery() { Query = wholeKeyword };
//    query = query || wholeWordQuery;
//}
//var searchResults = client.Search<Person>(s => s
//    .Index("zhixiao-application")
//    .Query(query)
//);

#endregion

#region 指定属性搜索

//使用term Query
//Term是一个被索引的精确值，也就是说Foo, foo, FOO是不相等的，因此
//在使用term query的时候要注意，term query在搜索的Field已经被索引的时候，是不支持大写的。
// QueryContainer query2 = new TermQuery { Field = item.Key, Value = item.Value.ToLower() };
//--------------------------------------------------------------------------------------
//var searchResults = client.Search<PersonDetail>(s => s
//    .Index("elastic-search-app")
//    .Query(q => q.Term(t => t.OnField(f => f.LastName == "keyword")))
//);
//效果同上
//QueryContainer termQuery = new TermQuery { Field = "lastname", Value = "keyword" };
//var searchResults = client.Search<PersonDetail>(s => s
//    .Index("elastic-search-app")
//    .Query(termQuery)
//);
//--------------------------------------------------------------------------------------
//使用 Query String query
//QueryString query一般用于全文搜索，但是也可以用于单个属性的搜索（设置DefaultField属性），queryString query可以不区分大小写。QueryString还有一个好处就是我们可以搜索一个term中的一部分，
//例如lastname为"t Boterhuis 1"，那么我们可以用"terhuis"搜索到这个数据（虽然需要在外面包上**），在term query里面就做不到，因为ES把每一个属性的值都分析成一个个单独的term，提高了搜索的效率。
//keyword = "t Boterhuis 2";
//QueryContainer wholeWordQuery = new QueryStringQuery() { Query = keyword, DefaultOperator = Operator.And };
//var searchResults = client.Search<PersonDetail>(s => s
//    .Index("elastic-search-app")
//    .Query(wholeWordQuery)
//);

#endregion

return searchResults.Documents.ToList();
}

public List<PersonDetail> Sort(string keyword)
{
// 首先我们把原先的索引先删除了
var response =
client.DeleteIndex(
new DeleteIndexRequest(new IndexNameMarker()
{
Name = "elastic-search-app",
Type = typeof(PersonDetail)
}));

//然后重新创建索引
var indexResult = client.CreateIndex("PD-application");
var response1 = client.Map<PersonDetail>(m => m.MapFromAttributes());
IEnumerable<PersonDetail> persons = new List<PersonDetail>
{
new PersonDetail()
{
Id = 4,
FirstName = "Boterhuis-040",
LastName = "Gusto-040",
},
new PersonDetail()
{
Id = 5,
FirstName = "sales@historichousehotels.com",
LastName = "t Boterhuis 1",
},
new PersonDetail()
{
Id = 6,
FirstName = "Aberdeen #110",
LastName = "sales@historichousehotels.com",
},
new PersonDetail()
{
Id = 7,
FirstName = "Aberdeen #110",
LastName = "t Boterhuis 2",
},
};
foreach (var person in persons)
{
client.Index(person);
}
var searchResults = client.Search<PersonDetail>(s => s
.Index("PD-application")
.Sort(sort => sort.OnField(f => f.Id).Order(SortOrder.Ascending))

);
return searchResults.Documents.ToList();
}
}

public static class Util
{

//生成10000条sqlserver测试数据
public static List<PersonDetail> Get10000PersonDetails()
{
var personDetailsList = new List<PersonDetail>();

for (int i = 0; i < 10000; i++)
{
personDetailsList.Add(new PersonDetail()
{
FirstName = "FN" + new Random().Next(int.MaxValue),
LastName = "LN"  + new Random().Next(int.MaxValue)
});
}
return personDetailsList;
}

//生成10000条ElasticSearch测试数据
public static List<PersonDetail> Get10000PersonDetailsWithID()
{
var personDetailsList = new List<PersonDetail>();

for (int i = 0; i < 10000; i++)
{
personDetailsList.Add(new PersonDetail()
{
Id = i * new Random().Next(99),
FirstName = "FN" + new Random().Next(int.MaxValue),
LastName = "LN" + new Random().Next(int.MaxValue)
});
}
return personDetailsList;
}

}

public static class Setting
{
public static Uri Node
{
get
{
return new Uri("http://localhost:9200");
}
}
//连接配置
public static ConnectionSettings ConnectionSettings
{
get
{
return new ConnectionSettings(Node, defaultIndex: "es-index-app");
}
}

}

Model层代码:

public partial class PersonDetail
{
public long Id { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
}

public partial class PersonContext : DbContext
{
static PersonContext()
{
Database.SetInitializer<PersonContext>(null);
}

public PersonContext()
: base("Name=PersonContext")
{
}

public DbSet<PersonDetail> PersonDetails { get; set; }

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
//在重写OnModelCreating方法中则可以直接调用映射类，从而减少了OnModelCreating方法的复杂度，同时也增强了代码维护的可读性
modelBuilder.Configurations.Add(new PersonDetailMap());  //属性映射约定
}
}

//Fluent API配置Configuration映射类
public class PersonDetailMap : EntityTypeConfiguration<PersonDetail>
{
public PersonDetailMap()
{
// 主键
this.HasKey(t => new { t.Id, t.FirstName, t.LastName });

// 属性
this.Property(t => t.Id)
.HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);

this.Property(t => t.FirstName)
.IsRequired();

this.Property(t => t.LastName)
.IsRequired();

// 表 & 列 映射
this.ToTable("PersonDetails");
this.Property(t => t.Id).HasColumnName("Id");
this.Property(t => t.FirstName).HasColumnName("FirstName");
this.Property(t => t.LastName).HasColumnName("LastName");
}
}

sqlserver脚本:

USE [Person]
GO

SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[PersonDetails](
[Id] [bigint] IDENTITY(1,1) NOT NULL,
[FirstName] [nvarchar](max) NOT NULL,
[LastName] [nvarchar](max) NOT NULL
) ON [PRIMARY]

GO

结果图: