go读取consul配置文件

在上文我们的 go学习笔记:使用 consul 做服务发现和配置共享 这里我们单独来用viper实现读取consul的配置， 我习惯与用yaml格式， 所以 首先 新建yaml文件

store:
  book:
    - author: john
      price: 10
    - author: ken
      price: 12
  bicycle:
    color: red
    price: 19.95

可以直接调用viper.AddRemoteProvider读取远程配置， 也可以用github.com/hashicorp/consul/api 来读取consul的内容， 然后在用viper读取，整改代码如下：

package main


import (
    "bytes"
    "fmt"
    "log"
    "time"



    consulapi "github.com/hashicorp/consul/api"
    "github.com/hashicorp/consul/api/watch"
    "github.com/spf13/viper"
    _ "github.com/spf13/viper/remote"
)



var (
    defaultConfig *viper.Viper
    consulAddress string
    consulPath    string
)



func initConfig() *viper.Viper {
    consulAddress = "http://192.168.100.19:8500"
    consulPath = "config/v1/local"



    defaultConfig = viper.New()
    defaultConfig.SetConfigType("yaml")



    consulClient, err := consulapi.NewClient(&consulapi.Config{Address: consulAddress})
    if err != nil {
        log.Fatalln("consul连接失败:", err)
    }



    kv, _, err := consulClient.KV().Get(consulPath, nil)
    if err != nil {
        log.Fatalln("consul获取配置失败:", err)
    }



    err = defaultConfig.ReadConfig(bytes.NewBuffer(kv.Value))
    if err != nil {
        log.Fatalln("Viper解析配置失败:", err)
    }



    go watchConfig()



    return defaultConfig
}
func watchConfig() {
    time.Sleep(time.Second * 10)
    params := make(map[string]interface{})
    params["type"] = "key"
    params["key"] = consulPath



    w, err := watch.Parse(params)
    if err != nil {
        log.Fatalln(err)
    }
    w.Handler = func(u uint64, i interface{}) {
        kv := i.(*consulapi.KVPair)
        hotconfig := viper.New()
        hotconfig.SetConfigType("yaml")
        err = hotconfig.ReadConfig(bytes.NewBuffer(kv.Value))
        if err != nil {
            log.Fatalln("Viper解析配置失败:", err)
        }
        defaultConfig = hotconfig
    }
    err = w.Run(consulAddress)
    if err != nil {
        log.Fatalln("监听consul错误:", err)
    }
}
func GetConfig() *viper.Viper {
    if defaultConfig == nil {
        defaultConfig = initConfig()
    }
    return defaultConfig
}
func main() {
    ReadOne()



    go func() {
        for {
            host := GetConfig().GetString("store.bicycle.color")
            fmt.Println("consul===", host)
            time.Sleep(time.Second * 10)
        }



    }()



    select {}
}



func ReadOne() {
    runtimeConfig := viper.New()
    runtimeConfig.AddRemoteProvider("consul", "http://192.168.100.19:8500", "config/v1/local")
    runtimeConfig.SetConfigType("yaml")
    err := runtimeConfig.ReadRemoteConfig()
    if err != nil {
        log.Fatalln("viper read:", err)
    }
    err = runtimeConfig.WatchRemoteConfigOnChannel()
    if err != nil {
        log.Fatalln("viper watch err:", err)
    }
    go func() {
        for {
            host := runtimeConfig.GetString("store.bicycle.color")
            fmt.Println("viper=====", host)
            time.Sleep(time.Second * 10)
        }



    }()



}

如果遇到 google.golang.org/grpc/naming: module google.golang.org/grpc@latest found (v1.31.0), but does not contain package google.golang.org/grpc/naming 这样的错误，可以在go.mod文件增加:

replace google.golang.org/grpc => google.golang.org/grpc v1.21.1