Function preRun

cmd/ttn-lw-cli/commands/root.go:121–270

(tasks ...func() error)

func runNoop(cmd *cobra.Command, args []string) error { return nil }

func preRun(tasks ...func() error) func(cmd *cobra.Command, args []string) error {
	return func(cmd *cobra.Command, args []string) error {
		// read in config from file
		err := mgr.ReadInConfig()
		if err != nil {
			return err
		}

		// unmarshal config
		if err = mgr.Unmarshal(config); err != nil {
			return err
		}

		// enable configured experimental features
		experimental.EnableFeatures(config.Experimental.Features...)

		// create input decoder on Stdin
		if rd, ok := cmdio.BufferedPipe(os.Stdin); ok {
			inputDecoder, err = getInputDecoder(rd)
			if err != nil {
				return err
			}
		}

		// get cache
		cache, err = util.GetAuthCache()
		if err != nil {
			return err
		}
		cache = cache.ForID(config.CredentialsID)

		// create logger
		logger, err = shared.InitializeLogger(&config.Log)
		if err != nil {
			return err
		}

		ctx = log.NewContext(ctx, logger)

		// Start the version check in background.
		// The result is waited in the post run.
		versionUpdate = make(chan *pkgversion.Update)
		if config.SkipVersionCheck {
			close(versionUpdate)
		} else {
			go func(ctx context.Context) {
				defer close(versionUpdate)
				update, err := pkgversion.CheckUpdate(ctx)
				if err != nil {
					log.FromContext(ctx).WithError(err).Warn("Failed to check version update")
				} else if update != nil {
					versionUpdate <- update
				} else {
					log.FromContext(ctx).Debug("No new version available")
				}
			}(ctx)
		}