• ElasticSearch-.net平台下c#操作ElasticSearch详解


    ElasticSearch系列学习

    ElasticSearch第一步-环境配置

    ElasticSearch第二步-CRUD之Sense 

    ElasticSearch第三步-中文分词

    ElasticSearch第四步-查询详解

    ElasticSearch第五步-.net平台下c#操作ElasticSearch详解

      

    前面我们讲解了关于ElasticSearch的安装配置,以及CRUD

    本章我将讲解怎么使用c#操作ElasticSearch。

    首先你需要一定的技术储备,比如:asp.net webapi,mvc,jsonp,knockout。这些知识在这里不再讲解,请自行Google。

    项目DEMO介绍

    搜索和索引功能我是以服务(webapi项目)方式提供的,在客户端(mvc项目)中的view视图中,直接使用ajax(jsonp格式)方式调用webapi,然后使用knockout绑定到table上的。

    项目结构如图:

    引入驱动

    工欲善其事必先利其器,首先我们需要在Supernova.Webapi层中引入操作ElasticSearch的驱动dll PlainElastic.Net。

    如图:

    封装操作ElasticSearch的ElasticSearchHelper

     View Code

    demo中涉及的实体对象模型

    复制代码
    /// <summary>
        /// ik分词结果对象
        /// </summary>
        public class ik
        {
            public List<tokens> tokens { get; set; }
        }
        public class tokens
        {
            public string token { get; set; }
            public int start_offset { get; set; }
            public int end_offset { get; set; }
            public string type { get; set; }
            public int position { get; set; }
        }
    
        /// <summary>
        /// 测试数据对象
        /// </summary>
        public class personList
        {
            public personList()
            {
                this.list = new List<person>();
            }
            public int hits { get; set; }
            public int took { get; set; }
            public List<person> list { get; set; }
        }
        public class person
        {
            public string id { get; set; }
            public string name { get; set; }
            public int age { get; set; }
            public bool sex { get; set; }
            public DateTime birthday { get; set; }
            public string intro { get; set; }
        }
    复制代码

    详细介绍ElasticSearchHelper里面的方法

    1.索引文档(注意:索引文档之前先用配置filed对应的ik分词):

    复制代码
     public IndexResult Index(string indexName, string indexType, string id, string jsonDocument)
            {
                
                var serializer = new JsonNetSerializer();
                string cmd = new IndexCommand(indexName, indexType, id);
                OperationResult result = Client.Put(cmd, jsonDocument);
    
                var indexResult = serializer.ToIndexResult(result.Result);
                return indexResult;
            }
            public IndexResult Index(string indexName, string indexType, string id, object document)
            {
                var serializer = new JsonNetSerializer();
                var jsonDocument = serializer.Serialize(document);
                return Index(indexName, indexType, id, jsonDocument);
            }
    复制代码

    2.对单个字段的全文检索,字段intro 包含词组key中的任意一个单词。例如:词组(中国美好),只要每条数据的intro字段包含"中国"或者"美好"就返回。

    复制代码
    public personList Search<person>(string indexName, string indexType, string key,int from ,int size)
            {
                string cmd = new SearchCommand(indexName, indexType);
                string query = new QueryBuilder<person>()
                    //1 查询
                    .Query(b =>
                                b.Bool(m =>
                                    //并且关系
                                    m.Must(t =>
    
                                        //分词的最小单位或关系查询
                                       t.QueryString(t1=>t1.DefaultField("intro").Query(key))
                                       //.QueryString(t1 => t1.DefaultField("name").Query(key))
                                       // t .Terms(t2=>t2.Field("intro").Values("研究","方鸿渐"))
                                       //范围查询
                                        // .Range(r =>  r.Field("age").From("100").To("200") )  
                                         )
                                      )
                                    )
                      //分页
                     .From(from)
                     .Size(size)
                     //排序
                    // .Sort(c => c.Field("age", SortDirection.desc))
                      //添加高亮
                      .Highlight(h => h
                          .PreTags("<b>")
                          .PostTags("</b>")
                          .Fields(
                                 f => f.FieldName("intro").Order(HighlightOrder.score),
                                 f => f.FieldName("_all")
                                 )
                         )
                        .Build();
    
    
                string result = Client.Post(cmd, query);
                var serializer = new JsonNetSerializer();
                var list = serializer.ToSearchResult<Supernova.Webapi.DbHelper.person>(result);
                personList datalist = new personList();
                datalist.hits = list.hits.total;
                datalist.took = list.took;
                 var personList= list.hits.hits.Select(c => new Supernova.Webapi.DbHelper.person() {
                     id=c._source.id, 
                     age=c._source.age,
                     birthday =c._source.birthday, 
                     intro=string.Join("",c.highlight["intro"]), //高亮显示的内容,一条记录中出现了几次
                     name=c._source.name,
                     sex=c._source.sex,
                     
                 });
                 datalist.list.AddRange(personList);
                 return  datalist;
    
    
            }
    复制代码

    3.字段intro 或者name 包含词组key中的所有单词。例如:词组(中国美好),只要每条数据的intro或者name字段包含"中国"并且包含"美好"就返回。

    复制代码
       public personList SearchFullFileds<person>(string indexName, string indexType, string key, int from, int size)
            {
                MustQuery<person> mustNameQueryKeys = new MustQuery<person>();
                MustQuery<person> mustIntroQueryKeys = new MustQuery<person>();
                var arrKeys = GetIKTokenFromStr(key);
                foreach (var item in arrKeys)
                {
                    mustNameQueryKeys = mustNameQueryKeys.Term(t3 => t3.Field("name").Value(item)) as MustQuery<person>;
                    mustIntroQueryKeys = mustIntroQueryKeys.Term(t3 => t3.Field("intro").Value(item)) as MustQuery<person>;
                }
                
                string cmd = new SearchCommand(indexName, indexType);
                string query = new QueryBuilder<person>()
                    //1 查询
                    .Query(b =>
                                b.Bool(m =>
                                    m.Should(t =>  
                                             t.Bool(m1 =>
                                                         m1.Must(
                                                                 t2 =>
                                                                     //t2.Term(t3=>t3.Field("name").Value("研究"))
                                                                     //   .Term(t3=>t3.Field("name").Value("方鸿渐"))  
                                                                     mustNameQueryKeys
                                                                 )
                                                    )
                                           )
                                   .Should(t =>
                                             t.Bool(m1 =>
                                                         m1.Must(t2 => 
                                                                         //t2.Term(t3 => t3.Field("intro").Value("研究"))
                                                                         //.Term(t3 => t3.Field("intro").Value("方鸿渐"))  
                                                                         mustIntroQueryKeys
                                                                )
                                                    )
                                          )
                                      )
                            )
                    //分页
                     .From(from)
                     .Size(size)
                    //排序
                    // .Sort(c => c.Field("age", SortDirection.desc))
                    //添加高亮
                      .Highlight(h => h
                          .PreTags("<b>")
                          .PostTags("</b>")
                          .Fields(
                                 f => f.FieldName("intro").Order(HighlightOrder.score),
                                  f => f.FieldName("name").Order(HighlightOrder.score)
                                 )
                         )
                        .Build();
    
    
                string result = Client.Post(cmd, query);
                var serializer = new JsonNetSerializer();
                var list = serializer.ToSearchResult<Supernova.Webapi.DbHelper.person>(result);
                personList datalist = new personList();
                datalist.hits = list.hits.total;
                datalist.took = list.took;
                var personList = list.hits.hits.Select(c => new Supernova.Webapi.DbHelper.person()
                {
                    id = c._source.id,
                    age = c._source.age,
                    birthday = c._source.birthday,
                    intro = c.highlight==null||!c.highlight.Keys.Contains("intro") ? c._source.intro : string.Join("", c.highlight["intro"]), //高亮显示的内容,一条记录中出现了几次
                    name = c.highlight==null||!c.highlight.Keys.Contains("name") ? c._source.name : string.Join("", c.highlight["name"]),
                    sex = c._source.sex
    
                });
                datalist.list.AddRange(personList);
                return datalist;
    
    
            }
    复制代码

    3.搜索age在1到500之间,并且字段intro 或者name 包含词组key中的所有单词。

    复制代码
     public personList SearchFullFiledss<person>(string indexName, string indexType, string key, int from, int size)
            {
                MustQuery<person> mustNameQueryKeys = new MustQuery<person>();
                MustQuery<person> mustIntroQueryKeys = new MustQuery<person>();
                var arrKeys = GetIKTokenFromStr(key);
                foreach (var item in arrKeys)
                {
                    mustNameQueryKeys = mustNameQueryKeys.Term(t3 => t3.Field("name").Value(item)) as MustQuery<person>;
                    mustIntroQueryKeys = mustIntroQueryKeys.Term(t3 => t3.Field("intro").Value(item)) as MustQuery<person>;
                }
    
                string cmd = new SearchCommand(indexName, indexType);
                string query = new QueryBuilder<person>()
                    //1 查询
                    .Query(b =>
                                b.Bool(m =>
                                    m.Must(t =>
                                              t.Range(r => r.Field("age").From("1").To("500"))
                                              .Bool(ms =>
                                                        ms.Should(ts =>  
                                                                 ts.Bool(m1 =>
                                                                             m1.Must(
                                                                                     t2 =>
                                                                                         //t2.Term(t3=>t3.Field("name").Value("研究"))
                                                                                         //   .Term(t3=>t3.Field("name").Value("方鸿渐"))  
                                                                                         //
                                                                                          mustNameQueryKeys
                                                                                     )
                                                                        )
                                                               )
                                                       .Should(ts =>
                                                                 ts.Bool(m1 =>
                                                                             m1.Must(t2 => 
                                                                                             //t2.Term(t3 => t3.Field("intro").Value("研究"))
                                                                                             //.Term(t3 => t3.Field("intro").Value("方鸿渐"))  
                                                                                             
                                                                                            //
                                                                                            mustIntroQueryKeys
                                                                                    )
                                                                        )
                                                              )
                                                          )
                                                            )      
                                                          )
                           )
                    //分页
                     .From(from)
                     .Size(size)
                    //排序
                    // .Sort(c => c.Field("age", SortDirection.desc))
                    //添加高亮
                      .Highlight(h => h
                          .PreTags("<b>")
                          .PostTags("</b>")
                          .Fields(
                                 f => f.FieldName("intro").Order(HighlightOrder.score),
                                  f => f.FieldName("name").Order(HighlightOrder.score)
                                 )
                         )
                        .Build();
    
    
                string result = Client.Post(cmd, query);
                var serializer = new JsonNetSerializer();
                var list = serializer.ToSearchResult<Supernova.Webapi.DbHelper.person>(result);
                personList datalist = new personList();
                datalist.hits = list.hits.total;
                datalist.took = list.took;
                var personList = list.hits.hits.Select(c => new Supernova.Webapi.DbHelper.person()
                {
                    id = c._source.id,
                    age = c._source.age,
                    birthday = c._source.birthday,
                    intro = c.highlight==null||!c.highlight.Keys.Contains("intro") ? c._source.intro : string.Join("", c.highlight["intro"]), //高亮显示的内容,一条记录中出现了几次
                    name = c.highlight==null||!c.highlight.Keys.Contains("name") ? c._source.name : string.Join("", c.highlight["name"]),
                    sex = c._source.sex
    
                });
                datalist.list.AddRange(personList);
                return datalist;
    
    
            }
    复制代码

    需要用到的方法:将语句用ik分词,返回分词结果的集合

    复制代码
     private List<string> GetIKTokenFromStr(string key)
            {
                string s = "/db_test/_analyze?analyzer=ik";
                var result = Client.Post(s, "{"+key+"}");
                var serializer = new JsonNetSerializer();
                var list = serializer.Deserialize(result, typeof(ik)) as ik;            
                return list.tokens.Select(c=>c.token).ToList();
            }
    复制代码

    ASP.NET WebApi 调用ElasticSearchHelper

    1.首先我们添加一个基类ApiController

    复制代码
     public class BaseApiController : ApiController
        {
    
            public MongoDatabase db;
            public MongoCollection col = null;//用于直接返回查询的json       
            public BaseApiController() { }
            public BaseApiController(string collectionName)
            {
                db = DbHelper.MongodbHelper.Instance.DB;
                col = db.GetCollection(collectionName);
            }
            public string GetStringRequest(string paramter)
            {
                return HttpContext.Current.Request.QueryString[paramter] ?? "";
            }
            public int? GetIntRequest(string paramter)
            {
                string tmp = HttpContext.Current.Request.QueryString[paramter] ?? "";
                int tag = 0;
                if (!int.TryParse(tmp, out tag))
                {
                    return null;
                }
                return tag;
            }
        }
    复制代码

    2.操作ElasticSearch的apicontroller如下:

     View Code

    3.索引数据的api如下:

    复制代码
    /// <summary>
             /// 索引数据
            /// </summary>
            /// <returns></returns>
             [Route("estest/index")]
             [HttpGet]
             public object index()
             {             
                 int length = S.test.Length;
                 Random rd = new Random();
                 Random rdName = new Random();
                 ParallelOptions _po = new ParallelOptions();
                 _po.MaxDegreeOfParallelism = 4;
                 Parallel.For(0, 10000000, _po, c =>
                 {
    
                     var start = rd.Next(0, S.test.Length - 700);
                     var startName = rd.Next(0, S.test.Length - 30);
                     person p = new person() { age = DateTime.Now.Millisecond, birthday = DateTime.Now, id = Guid.NewGuid().ToString(), intro = S.test.Substring(start, 629) + c, name = S.test.Substring(startName, 29) + c, sex = true };
                     ElasticSearchHelper.Intance.Index("db_test", "person", Guid.NewGuid().ToString(), p);
                 });
                 return 1;
             }
    复制代码

    索引使用的测试数据如下:

     View Code

    4.搜索api如下:

    复制代码
    [Route("estest")]
            [HttpGet]
            public object Search()
            {
                 //1 搜索数据
                string key = GetStringRequest("Key");
                int? from = GetIntRequest("from");
                int? size = GetIntRequest("size");
                 
                return ElasticSearchHelper.Intance.Search<person>("db_test", "person", key ?? "方鸿渐", from == null ? 0 : from.Value, size == null ? 20 : size.Value);
    
                 
                 
            }
             [Route("estest/SearchFullFileds")]
             [HttpGet]
             public object SearchFullFileds()
             {
                 //1 搜索数据
                 string key = GetStringRequest("Key");
                 int? from = GetIntRequest("from");
                 int? size = GetIntRequest("size");             
                 return ElasticSearchHelper.Intance.SearchFullFileds<person>("db_test", "person", key ?? "方鸿渐", from == null ? 0 : from.Value, size == null ? 20 : size.Value);
    
    
    
             }
             [Route("estest/SearchFullFiledss")]
             [HttpGet]
             public object SearchFullFiledss()
             {
                 //1 搜索数据
                 string key = GetStringRequest("Key");
                 int? from = GetIntRequest("from");
                 int? size = GetIntRequest("size");            
                 return ElasticSearchHelper.Intance.SearchFullFiledss<person>("db_test", "person", key ?? "方鸿渐", from == null ? 0 : from.Value, size == null ? 20 : size.Value);
    
    
    
             }
    复制代码

    WebSite中的view视图调用webapi

    说明:我是直接使用ajax(jsop格式)调用webapi,返回的数据直接用knockout绑定到table中的。

    视图代码如下:

    复制代码
    @{
        ViewBag.Title = "ElasticSearch测试";
        Layout = null;
    }
    <link href="~/Content/bootstrap.css" rel="stylesheet" />
    <script src="~/Scripts/jquery-2.1.3.min.js"></script>
    <script src="~/Scripts/knockout-3.3.0.js"></script>
    <style>
        b{
            color:red;
        }
    </style>
    <script>
        $(function () {
            function ViewModel() {
                self = this;
                self.getData = ko.observableArray();
                //定义加载数据方法
                self.loadData = function () {
                    $.get("http://192.168.0.230/api/estest//SearchFullFiledss", { key: "@Request.QueryString["key"]", from: "@Request.QueryString["from"]", size: "@Request.QueryString["size"]" }, function (data) {
                        // alert(data.hits);
                        // alert(data.list.length);
                        $("#count").text("符合条件的数据供:" + data.hits + "  共花费了:" + data.took + "毫秒");
                       
                        $.each(data.list, function (i) {
                            var date=data.list[i].birthday;
                           
                        });
                        self.getData(data.list);
                    }, "jsonp");
                };
                //调用定义方法
                self.loadData();
            }
            ko.applyBindings(new ViewModel());
    
        });
    
    
    </script>
    <div id="count"></div>
    
    <div class="row">
        <table class="table-bordered table-condensed table-hover table-striped">
            <tbody data-bind="foreach: getData">
                <tr>
                    <td data-bind="text: id" />
                    <td data-bind="html: name" />
                    <td data-bind="text: sex" />
                    <td data-bind="text: age" />                
                    <td data-bind="text: birthday" />
                    <td data-bind="html: intro" />
                </tr>
            </tbody>
        </table>
    </div>
    <script>
    
    </script>
    复制代码

    搜索结果测试如下(我是用"api/estest//SearchFullFiledss"这个api测试的,搜索age在1到500之间,并且字段intro 或者name 包含词组key中的所有单词。):

    1.首先我们看一看测试数据总共有多少:

    我们可以看到总共db_test中总共有两千多万条数据。

    搜索测试1

    测试条件:key=上海方鸿渐&from=0&size=100,key指搜索关键短语,0是从第0条开始区数据,100是指取一百条数据,隐藏条件是age大于1小于500

    我们可以看到,首次搜索时,两千多万条数据大约耗时3.5秒,这里还包括取100条数据的时间,如果把数据改为20条则会更快。这里的硬件配置还只限于我的本机测试(内存8G,处理器Intel i5-4590 3.3GHZ)。

    搜索测试2

    测试条件同测试1:key=上海方鸿渐&from=0&size=100,key指搜索关键短语,0是从第0条开始区数据,100是指取一百条数据,隐藏条件是age大于1小于500

    我们可以看到,搜索耗时降到了大约1.5秒。这说明同一个关键词搜索越频繁,搜索速度越快,这是因为ElasticSearch会自动将搜索的内容缓存到内存中。

    搜索测试3

    测试条件:key=香烟德国&from=0&size=20,key指搜索关键短语,0是从第0条开始区数据,20是指取一百条数据,隐藏条件是age大于1小于500

    搜索测试4

    测试条件同测试3,二次相同条件搜索:key=香烟德国&from=0&size=20,key指搜索关键短语,0是从第0条开始区数据,20是指取一百条数据,隐藏条件是age大于1小于500

    我们可以看到,在二次搜索条件相同,搜索数据降低到20条的时候,只耗时不到0.5秒。

    本章完……

    ElasticSearch系列学习 

    ElasticSearch第一步-环境配置

    ElasticSearch第二步-CRUD之Sense 

    ElasticSearch第三步-中文分词

    ElasticSearch第四步-查询详解

    ElasticSearch第五步-.net平台下c#操作ElasticSearch详解

     

    http://www.cnblogs.com/eggTwo/p/4425269.html

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  • 原文地址:https://www.cnblogs.com/soundcode/p/9055841.html
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