通过Go接入集群

准备工作

• CSS集群处于可用状态。
• 确保运行Go代码的服务器与CSS集群的网络是互通的。
• 确认服务器已安装Go，Go官网下载地址：https://go.dev/dl/。

连接非安全集群

连接非安全集群，示例代码如下：

package main

import (
	"github.com/elastic/go-elasticsearch/v7"
	"log"
)

func main() {
	cfg := elasticsearch.Config{
		Addresses: []string{
			"http://HOST:9200/",
		},
	}

	es, _ := elasticsearch.NewClient(cfg)
	log.Println(es.Info())
}

连接安全集群

• 连接未开启https的安全集群，示例如下：

  package main
  
  import (
  	"github.com/elastic/go-elasticsearch/v7"
  	"log"
  )
  
  func main() {
  	cfg := elasticsearch.Config{
  		Addresses: []string{
  			"http://HOST:9200/",
  		},
  		Username: "USERNAME",
  		Password: "PASSWORD",
  	}
  
  	es, _ := elasticsearch.NewClient(cfg)
  	log.Println(es.Info())
  }

• 连接开启https的安全集群，不使用证书，示例代码如下：

  package main
  
  import (
  	"crypto/tls"
  	"github.com/elastic/go-elasticsearch/v7"
  	"log"
  	"net/http"
  )
  
  func main() {
  	cfg := elasticsearch.Config{
  		Addresses: []string{
  			"https://HOST:9200/",
  		},
  		Username: "USERNAME",
  		Password: "PASSWORD",
  		Transport: &http.Transport{
  			TLSClientConfig: &tls.Config{
  				InsecureSkipVerify: true,
  			},
  		},
  	}
  
  	es, _ := elasticsearch.NewClient(cfg)
  	log.Println(es.Info())
  }

• 连接开启https的安全集群，使用证书，示例代码如下：

  package main
  
  import (
  	"crypto/tls"
  	"crypto/x509"
  	"flag"
  	"github.com/elastic/go-elasticsearch/v7"
  	"io/ioutil"
  	"log"
  	"net"
  	"net/http"
  	"time"
  )
  
  func main() {
  	insecure := flag.Bool("insecure-ssl", false, "Accept/Ignore all server SSL certificates")
  	flag.Parse()
  
  	// Get the SystemCertPool, continue with an empty pool on error
  	rootCAs, _ := x509.SystemCertPool()
  	if rootCAs == nil {
  		rootCAs = x509.NewCertPool()
  	}
  
  	// Read in the cert file
  	certs, err := ioutil.ReadFile("/tmp/CloudSearchService.cer")
  	if err != nil {
  		log.Fatalf("Failed to append %q to RootCAs: %v", "xxx", err)
  	}
  
  	// Append our cert to the system pool
  	if ok := rootCAs.AppendCertsFromPEM(certs); !ok {
  		log.Println("No certs appended, using system certs only")
  	}
  
  	config := elasticsearch.Config{
  		Addresses: []string{
  			"https://HOST:9200/",
  		},
  		Username: "USERNAME",
  		Password: "PASSWORD",
  		Transport: &http.Transport{
  			MaxIdleConnsPerHost:   10,
  			ResponseHeaderTimeout: time.Second,
  			DialContext: (&net.Dialer{
  				Timeout:   30 * time.Second,
  				KeepAlive: 30 * time.Second,
  			}).DialContext,
  			TLSClientConfig: &tls.Config{
  				InsecureSkipVerify: *insecure,
  				RootCAs:            rootCAs,
  			},
  		},
  	}
  	es, _ := elasticsearch.NewClient(config)
  	log.Println(elasticsearch.Version)
  	log.Println(es.Info())
  }

运行代码

根据集群类型将以上适配的代码写入到EsTest.gc文件并存放到一个单独的目录，在该目录执行以下命令：

go env -w GO111MODULE=on
go env -w GOPROXY=https://repo.huaweicloud.com/repository/goproxy/ 
go env -w GONOSUMDB=*

go mod init test
go mod tidy
go run EsTest.go