golang模块viper读取配置文件

viper.SetDefault("time", "2019-7-14")
viper.SetDefault("notifyList", []string{"maple","ffm"})

package main

import (
    "fmt"
    "github.com/fsnotify/fsnotify"
    "github.com/spf13/viper"
)
viper:=viper.New()
viper.WatchConfig()
viper.OnConfigChange(func(e fsnotify.Event) {
  fmt.Println("Config file changed:", e.Name)
})

#json文件
{
  "appId": "123456789",
  "secret": "maple123456",
  "host": {
    "address": "localhost",
    "port": 5799
  }
}

package main

import (
    "fmt"
    "github.com/spf13/viper"
)

//定义config结构体
type Config struct {
    AppId string
    Secret string
    Host Host
}
//json中的嵌套对应结构体的嵌套
type Host struct {
    Address string
    Port int
}

func main() {
    config := viper.New()
    config.AddConfigPath("./kafka_demo")
    config.SetConfigName("config")
    config.SetConfigType("json")
    if err := config.ReadInConfig(); err != nil {
        panic(err)
    }
    fmt.Println(config.GetString("appId"))
    fmt.Println(config.GetString("secret"))
    fmt.Println(config.GetString("host.address"))
    fmt.Println(config.GetString("host.port"))

    //直接反序列化为Struct
    var configjson Config
    if err :=config.Unmarshal(&configjson);err !=nil{
        fmt.Println(err)
    }

    fmt.Println(configjson.Host)
    fmt.Println(configjson.AppId)
    fmt.Println(configjson.Secret)

}