config.go

// Load parses the orderer.yaml file and environment, producing a struct suitable for config use
func Load() *TopLevel {
    config := viper.New()
    cf.InitViper(config, configName)

    // for environment variables
    config.SetEnvPrefix(Prefix)
    config.AutomaticEnv()
    replacer := strings.NewReplacer(".", "_")
    config.SetEnvKeyReplacer(replacer)

    err := config.ReadInConfig()
    if err != nil {
        logger.Panic("Error reading configuration:", err)
    }

    var uconf TopLevel
    err = viperutil.EnhancedExactUnmarshal(config, &uconf)
    if err != nil {
        logger.Panic("Error unmarshaling config into struct:", err)
    }

    uconf.completeInitialization(filepath.Dir(config.ConfigFileUsed()))

    return &uconf
}

从 orderer.yaml 和环境变量中读取 Orderer 的配置信息，并构建一棵配置树结构。