1、前提

1.1 docker 安装elasticsearch

• 查询elasticsearch 版本

  docker search elasticsearch

• 将对应的版本拉到本地

   docker.elastic.co/elasticsearch/elasticsearch:7.3.0

• 创建一个网络

     docker network create esnet

• 启动容器

    docker run --name es  -p 9200:9200 -p 9300:9300  --network esnet -e "discovery.type=single-node" bdaab402b220

1.2这里过后就可以去写go代码 为了直观搞了个可视化工具 ElisticHD 这里使用docker 部署

  docker run -p 9800:9800 -d --link es:demo  --network esnet -e "discovery.type=single-node"  containerize/elastichd

可以试一下界面还是很美观的

捕获.PNG

2、golang 实现elasticsearch 简单的增删改查

直接上代码：

package mainimport (    "context"    "encoding/json"    "fmt"    "github.com/olivere/elastic/v7"    "reflect")var client *elastic.Clientvar host = "http://ip:port"type Employee struct {    FirstName string   `json:"first_name"`    LastName  string   `json:"last_name"`    Age       int      `json:"age"`    About     string   `json:"about"`    Interests []string `json:"interests"`}//初始化func init() {    //errorlog := log.New(os.Stdout, "APP", log.LstdFlags)    var err error            //这个地方有个小坑 不加上elastic.SetSniff(false) 会连接不上     client, err = elastic.NewClient(elastic.SetSniff(false), elastic.SetURL(host))    if err != nil {        panic(err)    }    _,_,err = client.Ping(host).Do(context.Background())    if err != nil {        panic(err)    }    //fmt.Printf("Elasticsearch returned with code %d and version %s\n", code, info.Version.Number)    _,err = client.ElasticsearchVersion(host)    if err != nil {        panic(err)    }    //fmt.Printf("Elasticsearch version %s\n", esversion)}/*下面是简单的CURD*///创建func create() {    //使用结构体    e1 := Employee{"Jane", "Smith", 32, "I like to collect rock albums", []string{"music"}}    put1, err := client.Index().        Index("megacorp").        Type("employee").        Id("1").        BodyJson(e1).        Do(context.Background())    if err != nil {        panic(err)    }    fmt.Printf("Indexed tweet %s to index s%s, type %s\n", put1.Id, put1.Index, put1.Type)    //使用字符串    e2 := `{"first_name":"John","last_name":"Smith","age":25,"about":"I love to go rock climbing","interests":["sports","music"]}`    put2, err := client.Index().        Index("megacorp").        Type("employee").        Id("2").        BodyJson(e2).        Do(context.Background())    if err != nil {        panic(err)    }    fmt.Printf("Indexed tweet %s to index s%s, type %s\n", put2.Id, put2.Index, put2.Type)    e3 := `{"first_name":"Douglas","last_name":"Fir","age":35,"about":"I like to build cabinets","interests":["forestry"]}`    put3, err := client.Index().        Index("megacorp").        Type("employee").        Id("3").        BodyJson(e3).        Do(context.Background())    if err != nil {        panic(err)    }    fmt.Printf("Indexed tweet %s to index s%s, type %s\n", put3.Id, put3.Index, put3.Type)}//查找func gets() {    //通过id查找    get1, err := client.Get().Index("megacorp").Type("employee").Id("2").Do(context.Background())    if err != nil {        panic(err)    }    if get1.Found {        fmt.Printf("Got document %s in version %d from index %s, type %s\n", get1.Id, get1.Version, get1.Index, get1.Type)        var bb Employee        err:=json.Unmarshal(get1.Source,&bb)        if err!=nil{            fmt.Println(err)        }        fmt.Println(bb.FirstName)        fmt.Println(string(get1.Source))    }}////删除func delete() {    res, err := client.Delete().Index("megacorp").        Type("employee").        Id("1").        Do(context.Background())    if err != nil {        println(err.Error())        return    }    fmt.Printf("delete result %s\n", res.Result)}////修改func update() {    res, err := client.Update().        Index("megacorp").        Type("employee").        Id("2").        Doc(map[string]interface{}{"age": 88}).        Do(context.Background())    if err != nil {        println(err.Error())    }    fmt.Printf("update age %s\n", res.Result)}//////搜索func query() {    var res *elastic.SearchResult    var err error    //取所有    res, err = client.Search("megacorp").Type("employee").Do(context.Background())    printEmployee(res, err)    //字段相等    q := elastic.NewQueryStringQuery("last_name:Smith")    res, err = client.Search("megacorp").Type("employee").Query(q).Do(context.Background())    if err != nil {        println(err.Error())    }    printEmployee(res, err)    //条件查询    //年龄大于30岁的    boolQ := elastic.NewBoolQuery()    boolQ.Must(elastic.NewMatchQuery("last_name", "smith"))    boolQ.Filter(elastic.NewRangeQuery("age").Gt(30))    res, err = client.Search("megacorp").Type("employee").Query(q).Do(context.Background())    printEmployee(res, err)    //短语搜索 搜索about字段中有 rock climbing    matchPhraseQuery := elastic.NewMatchPhraseQuery("about", "rock climbing")    res, err = client.Search("megacorp").Type("employee").Query(matchPhraseQuery).Do(context.Background())    printEmployee(res, err)    //分析 interests    aggs := elastic.NewTermsAggregation().Field("interests")    res, err = client.Search("megacorp").Type("employee").Aggregation("all_interests", aggs).Do(context.Background())    printEmployee(res, err)}//////简单分页func list(size,page int) {    if size < 0 || page < 1 {        fmt.Printf("param error")        return    }    res,err := client.Search("megacorp").        Type("employee").        Size(size).        From((page-1)*size).        Do(context.Background())    printEmployee(res, err)}////打印查询到的Employeefunc printEmployee(res *elastic.SearchResult, err error) {    if err != nil {        print(err.Error())        return    }    var typ Employee    for _, item := range res.Each(reflect.TypeOf(typ)) { //从搜索结果中取数据的方法        t := item.(Employee)        fmt.Printf("%#v\n", t)    }}func main() {    create()    delete()    update()    gets()    query()    list(2,1)}

有一个小坑要注意在代码中已经注释了，如果没有添加就会有下面错误

no active connection found: no Elasticsearch node available

解决

Docker No Elastic Node Aviable

关闭sniff模式；或者设置es的地址为publish_address 地址

代码设置sniff 为false

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