GO语言操作Elasticsearch

Elasticsearch简介

Elasticsearch 是一个开源的搜索引擎，建立在一个全文搜索引擎库 Apache Lucene™ 基础之上。 Lucene 可以说是当下最先进、高性能、全功能的搜索引擎库–无论是开源还是私有。

连接Elasticsearch

// 引入g~
~~~~~-elasticsearch
import (
    es8 "github.com/elastic/go-elasticsearch/v8"
)

// go-es配置
conf := es8.Config{
    Addresses: "http://127.0.0.1:9200",
    Username:"elastic",
    Password:"jloMQ7ZCTlcZUr_hmDoB",
}

// 创建
client, err := es8.NewClient(conf);
if err != nil{
    fmt.Println("=============  创建 elasticsearch 失败  =============")
    return 
}

// 连接
_, err1 := client.Info()
if err1 != nil{
    fmt.Println("=============  连接 elasticsearch 失败  =============")
    return 
}

创建索引

创建model结构体

type Admin struct{
    Id int `gorm:"<-" json:"id"` 
    UserName string `gorm:"<-" json:"user_name"` 
    RealName string `gorm:"<-" json:"real_name"` 
    Mobile string `gorm:"<-" json:"mobile"` 
}

初始化model

admin := Admin{
    Id: 1,
    UserName: "test",
    RealName: "测试",
    Mobile: "15222222222",
}

创建索引

// 结构体json序列化
str,err := json.Marshal(admin);
if err != nil{
    return ;
}

// 创建索引
res1, err1 := client.Index(
    "db.table",
    bytes.NewReader(str),
    client.Index.WithDocumentID("1"), // 索引ID
    client.Index.WithRefresh("true") //是否立即创建
);

搜索数据

创建返回结构体

type EsResponse struct{
    Hits struct{
        Total struct{
            Value int `json:"value"` 
        } `json:"total"` 
        Hits []struct{
            Index string `json:"_index"` 
            Id string `json:"_id"` 
            Score float32 `json:"_score"` 
            Source map[string]any `json:"_source"` 
        } `json:"hits"` 
    } `json:"hits"` 
}

type EsData struct{
    Total int `json:"total"` 
    List []map[string]any `json:"list"` 
}

搜索数据

query := map[string]any{
    "query":map[string]any{
        "bool":map[string]any{
            "must":[]map[string]any{
                map[string]any{
                    "match_phrase":map[string]any{
                        "user_name": "test",
                    },
                },
                map[string]any{
                    "match_phrase":map[string]any{
                        "mobile": "15222222222",
                    },
                },
            },
        },
    },
}

str,err := json.Marshal(query);
if err != nil{
    return ;
}

res1,err1 := client.Search(client.Search.WithBody(bytes.NewReader(str)));
    
if err1 != nil{
    return ;
}

解析数据

var resData EsResponse;
err2 := json.NewDecoder(res1.Body).Decode(&resData);
if err2 != nil{
    return ;
}

var esData EsData;
esData.Total = resData.Hits.Total.Value;
    
for _, v := range resData.Hits.Hits {
    cache := v.Source
    cache["_index"] = v.Index;
    cache["_id"] = v.Id;
    cache["_score"] = v.Score;
    esData.List = append(esData.List,cache)
}

修改数据

单条修改

 update := map[string]any{
    "script": map[string]any{
        "source":"ctx._source.user_name='test1';ctx._source.mobile='15211111111';",
        "lang": "painless",
    },
}

str,err1 := json.Marshal(update)
if err1 != nil{
    return ;
}

res2,err2 := client.Update(
    "db.table",
    "1",
    bytes.NewReader(str),
    client.Update.WithRefresh("true")
)

if err2 != nil{
    return ;
}

批量修改

update := map[string]any{
    "query":map[string]any{
        "bool":map[string]any{
            "must":[]map[string]any{
                map[string]any{
                    "match_phrase":map[string]any{
                        "user_name": "test",
                    },
                },
                map[string]any{
                    "match_phrase":map[string]any{
                        "mobile": "15222222222",
                    },
                },
            },
        },
    },
    "script": map[string]any{
        "source":"ctx._source.user_name='test1';ctx._source.mobile='15211111111';",
        "lang": "painless",
    },
}

str,err1 := json.Marshal(update)
if err1 != nil{
    return ;
}

res2,err2 := client.UpdateByQuery(
    []string{
        "db.table",
    },
    client.UpdateByQuery.WithBody(bytes.NewReader(str)),
    client.UpdateByQuery.WithRefresh(true)
)

if err2 != nil{
    return ;
}

删除数据

单条删除

res,err := client.Delete(
    "db.table",
    "1",
    client.Delete.WithRefresh("true")
)
if err != nil{
    return ;
}

批量删除

query := map[string]any{
    "query":map[string]any{
        "bool":map[string]any{
            "must":[]map[string]any{
                map[string]any{
                    "match_phrase":map[string]any{
                        "user_name": "test",
                    },
                },
                map[string]any{
                    "match_phrase":map[string]any{
                        "mobile": "15222222222",
                    },
                },
            },
        },
    },
}

str,err := json.Marshal(query);
if err != nil{
    return ;
}

res,err := client.DeleteByQuery(
    []string{
        "db.table",
    },
    bytes.NewReader(str),
    client.DeleteByQuery.WithRefresh(true)
)