code: func NewCommandlineConfigSource() core.ConfigSource {
  	cmdlineConfig := new(CommandLineConfigurationSource)
  	cmdlineConfig.priority = commandlinePriority
  	config, err := cmdlineConfig.pullCmdLineConfig()
  	if err != nil {
  		openlogging.GetLogger().Error("failed to initialize commandline configurations:" + err.Error())
  		return cmdlineConfig
  	}
  	cmdlineConfig.Configurations = config
  
  	return cmdlineConfig
  }
docs: //NewCommandlineConfigSource defines a fucntion used for creating configuration source