go get -u github.com/jinzaigo/xconfig

package main
import (
    "fmt"
    "github.com/jinzaigo/xconfig"
)
func main() {
    if xconfig.IsLocalLoaded() {
        fmt.Println("local config is loaded")
        return
    }
    //初始化
    configIns := xconfig.New(xconfig.WithFile("example/config.yml"))
    xconfig.InitLocalIns(configIns)
    //讀取配置
    fmt.Println(xconfig.GetLocalIns().GetString("appId"))
    fmt.Println(xconfig.GetLocalIns().GetString("env"))
    fmt.Println(xconfig.GetLocalIns().GetString("apollo.one.endpoint"))
}

//初始化
configIns := xconfig.New(xconfig.WithConfigType("properties"))
err := configIns.AddApolloRemoteConfig(endpoint, appId, namespace, backupFile)
if err != nil {
    ...handler
}
xconfig.AddRemoteIns("ApplicationConfig", configIns)
//讀取配置
fmt.Println(xconfig.GetRemoteIns("ApplicationConfig").AllSettings())

#apollo配置，支持多實(shí)例多namespace
apollo:
  one:
    endpoint: xxx
    appId: xxx
    namespaces:
      one:
        key: ApplicationConfig   #用于讀取配置，保證全局唯一，避免相互覆蓋
        name: application        #注意：name不要帶類型（例如application.properties），這里name和type分開配置
        type: properties
      two:
        key: cipherConfig
        name: cipher
        type: properties
    backupFile: /tmp/xconfig/apollo_bak/test.agollo #每個(gè)appId使用不同的備份文件名，避免相互覆蓋

package main
import (
    "fmt"
    "github.com/jinzaigo/xconfig"
)
type ApolloConfig struct {
    Endpoint   string                     `json:"endpoint"`
    AppId      string                     `json:"appId"`
    Namespaces map[string]ApolloNameSpace `json:"namespaces"`
    BackupFile string                     `json:"backupFile"`
}
type ApolloNameSpace struct {
    Key  string `json:"key"`
    Name string `json:"name"`
    Type string `json:"type"`
}
func main() {
    //本地配置初始化
    xconfig.InitLocalIns(xconfig.New(xconfig.WithFile("example/config.yml")))
    if !xconfig.GetLocalIns().IsSet("apollo") {
        fmt.Println("without apollo key")
        return
    }
    apolloConfigs := make(map[string]ApolloConfig, 0)
    err := xconfig.GetLocalIns().SubAndUnmarshal("apollo", &apolloConfigs)
    if err != nil {
        fmt.Println(apolloConfigs)
        fmt.Println("SubAndUnmarshal error:", err.Error())
        return
    }
    //多實(shí)例初始化
    for _, apolloConfig := range apolloConfigs {
        for _, namespaceConf := range apolloConfig.Namespaces {
            configIns := xconfig.New(xconfig.WithConfigType(namespaceConf.Type))
            err = configIns.AddApolloRemoteConfig(apolloConfig.Endpoint, apolloConfig.AppId, namespaceConf.Name, apolloConfig.BackupFile)
            if err != nil {
                fmt.Println("AddApolloRemoteConfig error:" + err.Error())
            }
            xconfig.AddRemoteIns(namespaceConf.Key, configIns)
        }
    }
    //讀取
    fmt.Println(xconfig.GetRemoteIns("ApplicationConfig").AllSettings())
}

v := viper.New()
v.SetConfigType("properties")
err := v.AddRemoteProvider("apollo", "http://endpoint", "application")
if err != nil {
    panic(fmt.Errorf("AddRemoteProvider error: %s", err))
}
fmt.Println("AddRemoteProvider success")
//執(zhí)行結(jié)果:
//panic: AddRemoteProvider error: Unsupported Remote Provider Type "apollo"

// SupportedRemoteProviders are universally supported remote providers.
var SupportedRemoteProviders = []string{"etcd", "consul", "firestore"}

import (
  "fmt"
  remote "github.com/shima-park/agollo/viper-remote"
  "github.com/spf13/viper"
)
remote.SetAppID("appId")
v := viper.New()
v.SetConfigType("properties")
err := v.AddRemoteProvider("apollo", "http://endpoint", "application")
if err != nil {
    panic(fmt.Errorf("AddRemoteProvider error: %s", err))
}
fmt.Println("AddRemoteProvider success")
//執(zhí)行結(jié)果:
//AddRemoteProvider success

//github.com/shima-park/agollo/viper-remote/remote.go 278-284行
func init() {
  viper.SupportedRemoteProviders = append(
    viper.SupportedRemoteProviders,
    "apollo",
  )
  viper.RemoteConfig = &configProvider{}
}
//github.com/spf13/viper/viper.go 113-120行
type remoteConfigFactory interface {
  Get(rp RemoteProvider) (io.Reader, error)
  Watch(rp RemoteProvider) (io.Reader, error)
  WatchChannel(rp RemoteProvider) (<-chan *RemoteResponse, chan bool)
}
// RemoteConfig is optional, see the remote package
var RemoteConfig remoteConfigFactory

//github.com/shima-park/agollo/viper-remote/remote.go 26行
var (
  // apollod的appid
  appID string
  ...
)
func SetAppID(appid string) {
  appID = appid
}
//github.com/shima-park/agollo/viper-remote/remote.go 252行
switch rp.Provider() {
...
case "apollo":
    return newApolloConfigManager(appID, rp.Endpoint(), defaultAgolloOptions)
}

//github.com/jinzaigo/xconfig/remote/remote.go
var (
  ...
  providers sync.Map
)
func init() {
  viper.RemoteConfig = &configProvider{} //目的：重寫viper.RemoteConfig的相關(guān)方法
}
type conf struct {
  appId string
  opts  []agollo.Option
}
//【重要】這里是實(shí)現(xiàn)支持多個(gè)appId的核心操作
func AddProviders(appId string, opts ...agollo.Option) string {
    provider := "apollo:" + appId
    _, loaded := providers.LoadOrStore(provider, conf{
        appId: appId,
        opts:  opts,
    })
    //之前未存儲(chǔ)過(guò)，則向viper新增一個(gè)provider，讓viper認(rèn)識(shí)這個(gè)新提供器
    if !loaded {
        viper.SupportedRemoteProviders = append(
            viper.SupportedRemoteProviders,
            provider,
        )
    }
    return provider
}
//使用的地方
func newApolloConfigManager(rp viper.RemoteProvider) (*apolloConfigManager, error) {
  //讀取provider相關(guān)配置
  providerConf, ok := providers.Load(rp.Provider())
  if !ok {
    return nil, ErrUnsupportedProvider
  }
  p := providerConf.(conf)
  if p.appId == "" {
    return nil, errors.New("The appid is not set")
  }
  ...
}

// 在github.com/spf13/viper/viper.go 1909行
// Retrieve the first found remote configuration.
func (v *Viper) watchKeyValueConfigOnChannel() error {
  if len(v.remoteProviders) == 0 {
    return RemoteConfigError("No Remote Providers")
  }
  for _, rp := range v.remoteProviders {
    respc, _ := RemoteConfig.WatchChannel(rp)
    // Todo: Add quit channel
    go func(rc <-chan *RemoteResponse) {
      for {
        b := <-rc
        reader := bytes.NewReader(b.Value)
        v.unmarshalReader(reader, v.kvstore)
      }
    }(respc)
    return nil
  }
  return RemoteConfigError("No Files Found")
}

//github.com/jinzaigo/xconfig/config.go
type Config struct {
    configType string
    viper      *viper.Viper
    viperLock  sync.RWMutex
}
//寫
//_ = c.viper.WatchRemoteConfigOnChannel()
respc, _ := viper.RemoteConfig.WatchChannel(remote.NewProviderSt(provider, endpoint, namespace, ""))
go func(rc <-chan *viper.RemoteResponse) {
    for {
        <-rc
        c.viperLock.Lock()
        err = c.viper.ReadRemoteConfig()
        c.viperLock.Unlock()
    }
}(respc)
//讀
func (c *Config) Get(key string) interface{} {
    c.viperLock.RLock()
    defer c.viperLock.RUnlock()
    return c.viper.Get(key)
}

//github.com/jinzaigo/xconfig/config.go 72行
func (c *Config) AddApolloRemoteConfig(endpoint, appId, namespace, backupFile string) error {
    ...
    //namespace默認(rèn)類型不用加后綴，非默認(rèn)類型需要加后綴（備注：這里會(huì)涉及到apollo變更通知后的熱加載操作 Start->longPoll）
    if c.configType != "properties" {
        namespace = namespace + "." + c.configType
    }
    ...
}
//config.yml配置說(shuō)明
namespaces:
    one:
        key: ApplicationConfig   #用于讀取配置，保證全局唯一，避免相互覆蓋
        name: application        #注意：name不要帶類型（例如application.properties），這里name和type分開配置
        type: properties