「Golang 反射实战」 - 我用反射写了一个配置库 - envutils ， 应用变更再也不会少变量了

type MysqlServer struct {
 ListenAddr string `env:"listenAddr"`
 Auth       string `env:"auth"`
 DBName     string `env:"dbName"`
}

func (my *MysqlServer) SetDefaults() {
 if my.ListenAddr == "" {
  my.ListenAddr = "localhost:3306"
 }
}

type RedisServer struct {
 DSN string `env:"dsn"`
}

func (r *RedisServer) SetDefaults() {
 if r.DSN == "" {
  r.DSN = "redis://:Password@localhost:6379/0"
 }
}

func Test_ConfP_Server(t *testing.T) {

// 1. 创建配置结构体
 config := &struct {
  MysqlServer *MysqlServer
  RedisServer *RedisServer
 }{
  MysqlServer: &MysqlServer{},
  RedisServer: &RedisServer{},
 }

// 2. 调用设置默认值
 err := CallSetDefaults(config)
 if err != nil {
  panic(err)
 }

// 3. 序列化配置
 data, err := Marshal(config, "AppName")
 if err != nil {
  panic(err)
 }
 fmt.Printf("%s\n", data)
}

AppName__MysqlServer_auth: "DbUser:DbPass"
AppName__MysqlServer_dbName: "default_db"
AppName__MysqlServer_listenAddr: 100.100.100.100:3306
AppName__RedisServer_dsn: redis://:YouPass@redis.example.com:6379/0

func Test_ConfP_Server(t *testing.T) {

 config := &struct {
  MysqlServer *MysqlServer
  RedisServer *RedisServer
 }{
  MysqlServer: &MysqlServer{},
  RedisServer: &RedisServer{},
 }

 err := UnmarshalFile(config, "AppName", "config.yml")
 if err != nil {
  panic(err)
 }

 fmt.Println("my_auth =>", config.MysqlServer.Auth)
 fmt.Println("redis_dsn =>", config.RedisServer.DSN)
}

my_auth => DbUser:DbPass
redis_dsn => redis://:YouPass@redis.example.com:6379/0