ubuntu安装elasticserach-golang使用
elasticserach 安装
Elasticsearch 是一个高可扩展性的开源全文本搜索和分析引擎。 它使你可以快速，近乎实时地存储，搜索和分析大量数据。 它通常用作支持具有复杂搜索功能和要求的应用程序的基础引擎/技术。
1.下载资源包
https://www.elastic.co/cn/downloads/elasticsearch
2.解压，本机解压到/home/yunlongchen/opt/elasticsearch中
tar elasticsearch-8.2.3-linux-x86_64.tar.gz
3.es为了安全性，不允许root用户操作，需使用普通用户模式
4.由于第三点的要求，该elasticsearch/config/elasticsearch.keystore文件属于root用户，故需将权限授予给普通用户
chown -R yunlongchen:yunlongchen /home/yunlongchen/elasticserach/
chown -R yunlongchen:yunlongchen /home/yunlongchen/opt/elasticsearch/elasticsearch-8.2.3/
chown -R yunlongchen:yunlongchen /home/yunlongchen/opt/elasticsearch/elasticsearch-8.2.3/config/elasticsearch.keystore
5.配置 ./config/elasticsearch.yml
23| node.name: node-1
path.data: /home/yunlongchen/opt/elasticsearch/elasticsearch-8.2.3/data
path.logs: /home/yunlongchen/opt/elasticsearch/elasticsearch-8.2.3/logs
network.host: 10.141.65.188 //修改成自己的IP
http.port: 9200
transport.profiles.default.port: 9301
discovery.seed_hosts: ["10.141.65.188:9301"]
cluster.initial_master_nodes: ["node-1"]
xpack.security.enabled: false
#装es-header需添加以下内容
http.cors.enabled: true
http.cors.allow-origin: "*"
http.cors.allow-headers: Authorization,X-Requested-With,Content-Length,Content-Type
6.启动es
yunlongchen@cyl:~/opt/elasticsearch/elasticsearch-8.2.3$ ./bin/elasticsearch
7.启动/安装时遇到的问题/注意事项：
１.es基于java，故需要安装jdk
2.错误：max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]
解决：编辑/etc/sysctl.conf，追加以下内容：
vm.max_map_count=655350
保存后，执行：sysctl -p
3.错误：max file descriptors [4096] for elasticsearch process is too low, increase to at least [65535]
ulimit -Hn： 是max number of open file descriptors的hard限制
ulimit -Sn： 是max number of open file descriptors的soft限制
yunlongchen@cyl:~/opt/elasticsearch/elasticsearch-8.2.3$ ulimit -Hn
4096
yunlongchen@cyl:~/opt/elasticsearch/elasticsearch-8.2.3$ ulimit -Sn
1024
解决：编辑 /etc/security/limits.conf，追加以下内容
* soft nofile 65535
* hard nofile 65535
yunlongchen soft nproc 4096
yunlongchen hard nproc 4096
# End of file
此文件修改后需要重新登录用户，才会生效
yunlongchen@cyl:~/opt/elasticsearch/elasticsearch-8.2.3$ ulimit -Sn
1024
yunlongchen@cyl:~/opt/elasticsearch/elasticsearch-8.2.3$ ulimit -Hn
4096
yunlongchen@cyl:~/opt/elasticsearch/elasticsearch-8.2.3$ sudo su
root@cyl:/home/yunlongchen/opt/elasticsearch/elasticsearch-8.2.3# su yunlongchenyunlongchen@cyl:~/opt/elasticsearch/elasticsearch-8.2.3$ ulimit -Sn
65535
yunlongchen@cyl:~/opt/elasticsearch/elasticsearch-8.2.3$ ulimit -Hn
65535
yunlongchen@cyl:~/opt/elasticsearch/elasticsearch-8.2.3$ ./bin/elasticsearch
4.错误：Transport SSL must be enabled if security is enabled. Please set [xpack.security.transport.ssl.enabled] to [true] or disable security by setting [xpack.security.enabled] to [false]
解决：修改../cofig/elasticsearch.yml文件，关闭安全设置
#action.destructive_requires_name: false
xpack.security.enabled: false
参考资料：
Ubuntu20.04安装elasticsearch8.1.3
ubuntu下安装elasticsearch7.5.1集群+kibana
Ubuntu 安装elasticsearch集群
centos8安装ElasticSearch8并配置
golang-es
使用第三方库"github.com/elastic/go-elasticsearch/v7"
注意：elasticsearch中创建index时，名字只能是小写字母，不支持大写字母，但支持＇_＇的使用，否则无法添加索引，
报错：
Bad Request] {“error”:{“root_cause”:[{“type”:“invalid_index_name_exception”,“reason”:“Invalid index name [nginxLog], must be lowercase”,“index_uuid”:“＿na＿”,“index”:“nginxLog”}],“type”:“invalid_index_name_exception”,“reason”:“Invalid index name [nginxLog], must be lowercase”
package main
import (
"context"
"encoding/json"
"fmt"
"log"
"strconv"
"strings"
"time"
"github.com/elastic/go-elasticsearch/v7"
"github.com/elastic/go-elasticsearch/v7/esapi"
)
type Tweet struct {
User string `json:"user"`
Message string `json:"message"`
}
func jsonStruct(Struct interface{}) string {
// Create struct instance of the Elasticsearch fields struct object
// Marshal the struct to JSON and check for errors
b, err := json.Marshal(Struct)
if err != nil {
fmt.Println("json.Marshal ERROR:", err)
return string(err.Error())
}
return string(b)
}
func main() {
// Allow for custom formatting of log output
log.SetFlags(0)
var (
r map[string]interface{}
// wg sync.WaitGroup
)
cfg := elasticsearch.Config{
Addresses: []string{
"http://10.141.65.188:9200",
},
Username: "user",
Password: "pass",
}
client, err := elasticsearch.NewClient(cfg)
if err != nil {
fmt.Println("cnnect es err,", err)
return
}
fmt.Println("conn es succ,", client)
// 1. Get cluster info
//
res, err := client.Info()
if err != nil {
log.Fatalf("Error getting response: %s", err)
}
// Check response status
if res.IsError() {
log.Fatalf("Error: %s", res.String())
}
// Deserialize the response into a map.
if err := json.NewDecoder(res.Body).Decode(&r); err != nil {
log.Fatalf("Error parsing the response body: %s", err)
}
// Print client and server version numbers.
log.Printf("Client: %s", elasticsearch.Version)
log.Printf("Server: %s", r["version"].(map[string]interface{})["number"])
log.Println(strings.Repeat("~", 37))
tweet := Tweet{User: "olivere", Message: "Take Five"}
bod := jsonStruct(tweet)
ctx := context.Background()
//index 类似数据库 Type 类似表的概念 BodyJosn存放实际的内容
// 链式操作，“.”返回的是对象
for i := 60; i < 70; i++ {
// Instantiate a request object
req := esapi.IndexRequest{
Index: "twitter",
DocumentID: strconv.Itoa(i + 1),
Body: strings.NewReader(bod),
Refresh: "true",
}
res, err := req.Do(ctx, client)
if err != nil {
log.Fatalf("IndexRequest ERROR: %s", err)
}
defer res.Body.Close()
// if res.IsError() {
// log.Printf("%s ERROR indexing document ID=%d", res.Status(), i+1)
// } else {
// // Deserialize the response into a map.
// var resMap map[string]interface{}
// if err := json.NewDecoder(res.Body).Decode(&resMap); err != nil {
// log.Printf("Error parsing the response body: %s", err)
// } else {
// log.Printf("\nIndexRequest() RESPONSE:")
// // Print the response status and indexed document version.
// fmt.Println("Status:", res.Status())
// fmt.Println("Result:", resMap["result"])
// fmt.Println("Version:", int(resMap["_version"].(float64)))
// fmt.Println("resMap:", resMap)
// fmt.Println("")
// }
// }
time.Sleep(time.Second * 2)
}
fmt.Println("insert succ")
}
Kibana安装
1.下载网址
https://www.elastic.co/cn/downloads/past-releases/
2.安装解压后，启动kibana,在非root用户执行
yunlongchen@cyl:~/opt/kibana/kibana-8.2.3$ ./bin/kibana
3.修改配置：在config/kibana.yml文件:
server.port: 5601
server.host: 10.141.65.189
elasticsearch.hosts: ["http://10.141.65.189:9200/"]
i18n.locale: "zh-CN"