Function main

go-example-telemetry-api-extension/main.go:34–106

()

var l = log.WithFields(log.Fields{"pkg": "main"})

func main() {
	l.Info("[main] Starting the Telemetry API extension")
	extensionName := path.Base(os.Args[0])

	ctx, cancel := context.WithCancel(context.Background())
	sigs := make(chan os.Signal, 1)
	signal.Notify(sigs, syscall.SIGTERM, syscall.SIGINT)
	go func() {
		s := <-sigs
		cancel()
		l.Info("[main] Received", s)
		l.Info("[main] Exiting")
	}()

	// Step 1 - Register the extension with Extensions API
	l.Info("[main] Registering extension")
	extensionApiClient := extensionApi.NewClient()
	extensionId, err := extensionApiClient.Register(ctx, extensionName)
	if err != nil {
		panic(err)
	}
	l.Info("[main] Registation success with extensionId", extensionId)

	// Step 2 - Start the local http listener which will receive data from Telemetry API
	l.Info("[main] Starting the Telemetry listener")
	telemetryListener := telemetryApi.NewTelemetryApiListener()
	telemetryListenerUri, err := telemetryListener.Start()
	if err != nil {
		panic(err)
	}

	// Step 3 - Subscribe the listener to Telemetry API
	l.Info("[main] Subscribing to the Telemetry API")
	telemetryApiClient := telemetryApi.NewClient()
	_, err = telemetryApiClient.Subscribe(ctx, extensionId, telemetryListenerUri)
	if err != nil {
		panic(err)
	}
	l.Info("[main] Subscription success")

	dispatcher := telemetryApi.NewDispatcher()

	// Will block until invoke or shutdown event is received or cancelled via the context.
	for {
		select {
		case <-ctx.Done():
			return
		default:
			l.Info("[main] Waiting for next event...")

			// This is a blocking action
			res, err := extensionApiClient.NextEvent(ctx)
			if err != nil {
				l.Error("[main] Exiting. Error:", err)
				return
			}

			// Dispatching log events from previous invocations