1. 首先，我定义了一个全局变量ESClient作为ES客户端的单例，并在启动初调用Init函数初始化它 ```go var hostlist []string{ “http://ip1:9200/“, “http://ip2:9200/“, “http://ip3:9200/“ }

    var ESClient *elastic.Client

    func InitEs() { var err error // 创建es连接，如果通过nat地址访问，为防止地址被自动转换，可加elastic.SetSniff(false) ESClient, err = elastic.NewClient(elastic.SetURL(hostlist…)) if err != nil { logs.Error(err) os.Exit(1) } for _, v := range hostlist { // 尝试请求es info, code, err := ESClient.Ping(v).Do(context.Background()) if err != nil { logs.Error(err) os.Exit(1) } logs.Info(“Elasticsearch Node %s returned with code %d and version %s\n”, v, code, info.Version.Number) esversion, err := ESClient.ElasticsearchVersion(v) logs.Info(“Elasticsearch Node %s version %s\n”, v, esversion) } }

    2. 2. 然后定义了一个查询入参，将查询字段的json与参数类型定义出来
    3. ```go
    4. // 查询入参
    5. type EventParam struct {
    6.     User    string `json:"username"`
    7.     Type    string `json:"logtype"`
    8.     Message string `json:"logmessage"`
    9.     Time    int64  `json:"logtime"`
    10. }
    1. 最后编写Search方法来进行查询
      1. func Search(req *EventParam, start,end,page, size int) ([]*eventti.EventParam, int, error) {
      2.  // 定义分页
      3.  if page < 1 {
      4.      page = 1
      5.  }
      6.  if size < 0 {
      7.      size = 10000
      8.  }
      9.  // 定义搜索的query
      10.  boolQuery := elastic.NewBoolQuery()
      11.  if req.User != "" {
      12.      boolQuery.Filter(elastic.NewMatchQuery("username", strings.ToLower(req.User)))
      13.  }
      14.  if req.Type != "" {
      15.      boolQuery.Filter(elastic.NewMatchQuery("logtype", req.Type))
      16.  }
      17.  if req.Message != "" {
      18.      boolQuery.Filter(elastic.NewMatchPhraseQuery("logmessage", req.Message))
      19.  }
      20.  // 定义查询时间范围
      21.  if req.Start != 0 && req.End != 0 {
      22.      boolQuery.Filter(elastic.NewRangeQuery("logtime").Gte(start), elastic.NewRangeQuery("logtime").Lte(end))
      23.  }
      24.  // 执行搜索
      25.  res, _ := models.ESClient.Search().Index("eventti-*").Type("doc").Query(boolQuery).Size(size).From((page - 1) * size).Do(context.Background())
      26.  var typ EventParam
      27.  resitemlist := make([]*eventti.EventParam, 0)
      28.  //从搜索结果中取数据，只会取EventParam定义的字段
      29.  for _, item := range res.Each(reflect.TypeOf(typ)) {
      30.      if t, ok := item.(EventParam); ok {
      31.          tmp := eventti.EventSearchResItem{
      32.              User:    t.User,
      33.              Message: t.Message,
      34.              Time:    strconv.FormatInt(t.Time, 10),
      35.              Type:    t.Type,
      36.          }
      37.          resitemlist = append(resitemlist, &tmp)
      38.      }
      39.  }
      40.  return resitemlist, len(resitemlist), nil
      41. }