在ElasticSearch 6.6和Nest 6.6中具有排序和分页变量的搜索模板

添加正确的搜索模板(在“下移动分页和排序” 来源 正如RussCam指出的那样),以防将来有人需要它。

POST _scripts/guest_person_by_email
{
  "script": {    
    "lang": "mustache",
    "source": """
     {
       "from": "{{from}}{{^from}}0{{/from}}",
       "size": "{{size}}{{^size}}5{{/size}}",
      "sort": [
      {
        "_script": {
          "order": "asc",
          "type": "number",
          "script": "return (doc['type'].value == 'person')? 0 : 1;"
        }
      },
      {
        "firstName": {
          "order": "asc"
        }
      },
      {
        "lastName": {
          "order": "asc"
        }
      }
    ],
      "query":{
        "bool":{
          "filter":{
            "terms":{
              "email":
              {{#toJson}}emails{{/toJson}}
            }
          }
        }
      }
    }
"""
  }
}

有几个问题

1. 索引模板定义 "email" 字段映射两次
2. 索引模板集 "dynamic" 错误,但不包含 "type" 字段映射,因此脚本排序将失败
3. 整个搜索请求需要在 "source" 对于Put脚本API调用

Nest可以帮助构建正确的搜索请求,并将其作为搜索模板的基础,除了使用客户端的其他一系列原因(如循环请求、自动故障转移和重试等)之外。

这是一个完整的例子

private static void Main()
{
    var defaultIndex = "person";
    var pool = new SingleNodeConnectionPool(new Uri("http://localhost:9200"));

    var settings = new ConnectionSettings(pool)
        .DefaultIndex(defaultIndex)
        .DefaultTypeName("_doc");

    var client = new ElasticClient(settings);

    // WARNING: This deletes the index to make this code repeatable.
    // You probably want to remove this if copying verbatim
    if (client.IndexExists(defaultIndex).Exists)
        client.DeleteIndex(defaultIndex);

    var indexTemplateResponse = client.LowLevel.IndicesPutTemplateForAll<PutIndexTemplateResponse>(
        "person_guest_template",
        @"{
          ""order"": 0,
          ""index_patterns"": [""person*"",""guest*""],
          ""settings"": {
            ""index"": {
              ""analysis"": {
                ""filter"": {
                  ""autoComplete_filter"": {
                    ""type"": ""edge_ngram"",
                    ""min_gram"": ""2"",
                    ""max_gram"": ""20""
                  }
                },
                ""analyzer"": {
                  ""autoComplete"": {
                    ""filter"": [""lowercase"", ""asciifolding"",""autoComplete_filter""],
                    ""type"": ""custom"",
                    ""tokenizer"": ""whitespace""
                  },
                  ""default"": {
                    ""filter"": [""lowercase"", ""asciifolding""],
                    ""type"": ""custom"",
                    ""tokenizer"": ""whitespace""
                  }
                }
              },
              ""number_of_shards"": ""3"",
              ""number_of_replicas"": ""1""
            }
          },
          ""mappings"": {
            ""_doc"": {
              ""dynamic"": false,
              ""properties"": {
                ""firstName"": {
                  ""type"": ""keyword"",
                  ""fields"": {
                    ""search"": {
                      ""type"": ""text"",
                      ""analyzer"": ""autoComplete"",
                      ""search_analyzer"": ""default""
                    }
                  }
                },
                ""lastName"": {
                  ""type"": ""keyword"",
                  ""fields"": {
                    ""search"": {
                      ""type"": ""text"",
                      ""analyzer"": ""autoComplete"",
                      ""search_analyzer"": ""default""
                    }
                  }
                },
                ""email"": {
                  ""type"": ""keyword""
                },
                ""type"": {
                  ""type"": ""keyword""
                }
              }
            }
          }
        }");

    // build a prototype search request     
    var searchRequest = new SearchRequest
    {
        From = 0,
        Size = 0,
        Sort = new List<ISort> 
        {
            new ScriptSort
            {
                Order = Nest.SortOrder.Ascending,
                Type = "number",
                Script = new InlineScript("return (doc['type'].value == 'person')? 0 : 1;")
            },
            new SortField
            {
                Field = "firstName",
                Order = Nest.SortOrder.Ascending
            },
            new SortField
            {
                Field = "lastName",
                Order = Nest.SortOrder.Ascending
            }
        },
        Query = new BoolQuery
        {
            Filter = new QueryContainer[] 
            {
                new TermsQuery
                {
                    Field = "email",
                    Terms = new[] { "emails" }
                }
            }
        }
    };

    var json = client.RequestResponseSerializer.SerializeToString(searchRequest);
    // create template from prototype search request
    var jObject = JsonConvert.DeserializeObject<JObject>(json); 
    jObject["from"] = "{{from}}{{^from}}0{{/from}}";
    jObject["size"] = "{{size}}{{^size}}5{{/size}}";    
    json = jObject.ToString(Newtonsoft.Json.Formatting.None);
    // below is invalid JSON, so can only be constructed with replacement
    json = json.Replace("[\"emails\"]", "{{#toJson}}emails{{/toJson}}");

    // add search template
    var putScriptResponse = client.PutScript("guest_person_by_email", s => s
        .Script(sc => sc
            .Lang(ScriptLang.Mustache)
            .Source(json)
        )
    );

    var person = new Person
    {
        FirstName = "Rennish",
        LastName = "Joseph",
        Email = new[] { "rennishj@test.com" }
    };

    // index document
    var indexResponse = client.Index(person, i => i.Id(1).Refresh(Refresh.WaitFor));

    // search
    var searchResponse = client.SearchTemplate<Person>(s => s
        .Id("guest_person_by_email")
        .Params(p => p
            .Add("emails", person.Email)
            .Add("from", 0)
            .Add("size", 50)
        )
    );
}

public class Person 
{
    public string FirstName {get;set;}
    public string LastName { get; set; }
    public string[] Email {get;set;}
    public string Type {get; set;} = "person";
}

搜索模板请求的结果是

{
  "took" : 47,
  "timed_out" : false,
  "_shards" : {
    "total" : 3,
    "successful" : 3,
    "skipped" : 0,
    "failed" : 0
  },
  "hits" : {
    "total" : 1,
    "max_score" : null,
    "hits" : [
      {
        "_index" : "person",
        "_type" : "_doc",
        "_id" : "1",
        "_score" : null,
        "_source" : {
          "firstName" : "Rennish",
          "lastName" : "Joseph",
          "email" : [
            "rennishj@test.com"
          ],
          "type" : "person"
        },
        "sort" : [
          0.0,
          "Rennish",
          "Joseph"
        ]
      }
    ]
  }
}