go之构建简单的web服务器3.0

引入etcd模块，实现对etcd的增删改。目录架构如下

etcd.go代码

package storage

import (
	"context"
	"time"
	"fmt"
    "errors"
	clientv3 "go.etcd.io/etcd/client/v3"
)

//连接etcd
func ConnectEtcd() (*clientv3.Client,error) {
    cli, err := clientv3.New(clientv3.Config{
        Endpoints:   []string{"127.0.0.1:2379"},
        DialTimeout: 5 * time.Second,
    })
    if err != nil {
        return nil,errors.New(fmt.Sprintf("connect to etcd failed, err:%v\n", err))
    }
   
    return cli,nil
}

//通过key获取value
//控制台命令：./etcdctl --endpoints=localhost:2379 get "/app"
func GetEtcdData(key string) ([]byte,error) {
	if  key == "" {
		return nil,errors.New("key不能为空")
	}
	//连接etcd
    cli,err := ConnectEtcd();
    if err != nil {
        return nil,err
    }
    defer cli.Close()
    ctx := context.TODO()
    kv := clientv3.NewKV(cli)//用newKv的方式获取键值对
    resp, err := kv.Get(ctx, key)
    
    if err != nil {
        return nil,errors.New(fmt.Sprintf("get from etcd failed, err:%v\n", err))
    }
    // fmt.Println(resp.Kvs) //[key:"foo" create_revision:2 mod_revision:3 version:2 value:"bar" ]
    // fmt.Println(len(resp.Kvs))
    if len(resp.Kvs) == 0 {
        return nil,errors.New("key未设置value")
    }
    // data["key"] = string(resp.Kvs[0].Key)
    // data["value"] = string(resp.Kvs[0].Value)
    // common.ReturnSuccess(w,conf.SUCCESS_CODE,"获取成功",data)
    return resp.Kvs[0].Value,nil
}


//通过前缀获取相关的key
//控制台命令：
// ./etcdctl --endpoints=localhost:2379 get "/app"  --prefix
func GetEtcdDataWithPrefix(prefix string) ([]*map[string]interface{},error){

	//连接etcd
    cli,err := ConnectEtcd();
    if err != nil {
        return nil,err
    }
    defer cli.Close()
    ctx := context.TODO()
    kv := clientv3.NewKV(cli)//用newKv的方式获取键值对
    //通过前缀获取key
    resp, err := kv.Get(ctx, prefix,clientv3.WithPrefix())
    
    if err != nil {
        return nil,errors.New(fmt.Sprintf("get from etcd failed, err:%v\n", err))
    }

    data := make([]*map[string]interface{},len(resp.Kvs))
    for k,v := range resp.Kvs {
        temp := make(map[string]interface{})
        temp["key"] = string(v.Key)
        temp["value"] = string(v.Value)
        data[k] = &temp
        // data = append(data,&temp)
    }
    return data,nil
}

//设置key
//控制台命令：./etcdctl put k1 v1
func SetEtcdData(key string, value string) error {
   
    if key == "" || value == "" {
        return errors.New("缺少key或value!!!")
    }
    //连接etcd
    cli,err := ConnectEtcd();
    if err != nil {
        return err
    }
    defer cli.Close()
    // put
    ctx := context.TODO()
    _, err = cli.Put(ctx, key, value)
    if err != nil {
        return errors.New(fmt.Sprintf("put to etcd failed, err:%v\n", err))
    }
    return nil
}

//删除key 
//控制台命令：./etcdctl del k1
func DelEtcdData(key string) error {

    if key == "" {
        return errors.New("key不能为空!!!")
    }
   //连接etcd
    cli,err := ConnectEtcd();
    if err != nil {
        return err
    }
    defer cli.Close()
   
    if _, err := cli.Delete(context.Background(), key); err != nil {
        return errors.New(fmt.Sprintf("delete failed, err:%v\n", err))
    }
    return nil
}

etcd模块下的etcd_edit.go直接调用edit.go的方法进行增删改查

package etcd

import (
	"net/http"
	"fmt"
    //内部包
	common "etcd_web/common"
	conf "etcd_web/config"
    storage "etcd_web/storage"
)


//通过key获取value
func GetEtcdData(w http.ResponseWriter, r *http.Request) {
	
	key := r.FormValue("key")
	if  key == "" {
		common.ReturnError(w,conf.FAIL_CODE,fmt.Sprintf("key不能为空"))
		return
	}
    //根据key获取value
	value,err := storage.GetEtcdData(key)
    if err != nil {
        //Error()方法返回错误类型的字符串
        common.ReturnError(w,conf.FAIL_CODE,err.Error())
        return
    }
    data := make(map[string]interface{})
    data["key"] = key
    data["value"] = string(value)
    
    common.ReturnSuccess(w,conf.SUCCESS_CODE,"获取成功",data)
}


//通过前缀获取相关的key
func GetEtcdDataWithPrefix(w http.ResponseWriter, r *http.Request) {
	prefix := r.FormValue("prefix")
	data,err := storage.GetEtcdDataWithPrefix(prefix)
    if err != nil {
        common.ReturnError(w,conf.FAIL_CODE,err.Error())
        return
    }
    common.ReturnSuccess(w,conf.SUCCESS_CODE,"获取成功",data)
}

//设置key
//控制台命令：./etcdctl put k1 v1
func SetEtcdData(w http.ResponseWriter, r *http.Request) {
    key := r.FormValue("key")
    value := r.FormValue("value")
    if key == "" || value == "" {
        common.ReturnError(w,conf.FAIL_CODE,"缺少key或value")
        return
    }

    err := storage.SetEtcdData(key,value);
    if err != nil {
        common.ReturnError(w,conf.FAIL_CODE,err.Error())
        return
    }
    common.ReturnSuccess(w,conf.SUCCESS_CODE,"设置成功",nil)
}

//删除key 
//控制台命令：./etcdctl del k1
func DelEtcdData(w http.ResponseWriter, r *http.Request) {
    key := r.FormValue("key")
    if key == "" {
        common.ReturnError(w,conf.FAIL_CODE,"key不能为空")
        return
    }

    err := storage.DelEtcdData(key)
    if err != nil {
        common.ReturnError(w,conf.FAIL_CODE,err.Error())
        return
    }
    common.ReturnSuccess(w,conf.SUCCESS_CODE,"删除成功",nil)
}