func()

in frontend/cmd/cmd.go [121:210]
71 lines of code
9 McCabe index (conditional complexity)

func (opts *FrontendOpts) Run() error {
	ctx := context.Background()

	logger := util.DefaultLogger()
	logger.Info(fmt.Sprintf("%s (%s) started", frontend.ProgramName, version.CommitSHA))

	// Initialize the global OpenTelemetry tracer.
	otelShutdown, err := frontend.ConfigureOpenTelemetryTracer(ctx, logger, semconv.CloudRegion(opts.location))
	if err != nil {
		return fmt.Errorf("could not initialize opentelemetry sdk: %w", err)
	}

	// Create the database client.
	cosmosDatabaseClient, err := database.NewCosmosDatabaseClient(
		opts.cosmosURL,
		opts.cosmosName,
		azcore.ClientOptions{
			// FIXME Cloud should be determined by other means.
			Cloud:           cloud.AzurePublic,
			PerCallPolicies: []policy.Policy{policyFunc(correlationIDPolicy)},
			TracingProvider: azotel.NewTracingProvider(otel.GetTracerProvider(), nil),
		},
	)
	if err != nil {
		return fmt.Errorf("failed to create the CosmosDB client: %w", err)
	}

	dbClient, err := database.NewDBClient(ctx, cosmosDatabaseClient)
	if err != nil {
		return fmt.Errorf("failed to create the database client: %w", err)
	}

	listener, err := net.Listen("tcp4", fmt.Sprintf(":%d", opts.port))
	if err != nil {
		return err
	}

	metricsListener, err := net.Listen("tcp4", fmt.Sprintf(":%d", opts.metricsPort))
	if err != nil {
		return err
	}

	// Initialize the Clusters Service Client.
	conn, err := sdk.NewUnauthenticatedConnectionBuilder().
		TransportWrapper(func(r http.RoundTripper) http.RoundTripper {
			return otelhttp.NewTransport(
				frontend.RequestIDPropagator(r),
			)
		}).
		URL(opts.clustersServiceURL).
		Insecure(opts.insecure).
		MetricsSubsystem("frontend_clusters_service_client").
		MetricsRegisterer(prometheus.DefaultRegisterer).
		Build()
	if err != nil {
		return err
	}

	csClient := ocm.ClusterServiceClient{
		Conn:                       conn,
		ProvisionerNoOpProvision:   opts.clusterServiceNoopDeprovision,
		ProvisionerNoOpDeprovision: opts.clusterServiceNoopDeprovision,
	}

	if opts.clusterServiceProvisionShard != "" {
		csClient.ProvisionShardID = api.Ptr(opts.clusterServiceProvisionShard)
	}

	if len(opts.location) == 0 {
		return errors.New("location is required")
	}
	logger.Info(fmt.Sprintf("Application running in %s", opts.location))

	f := frontend.NewFrontend(logger, listener, metricsListener, prometheus.DefaultRegisterer, dbClient, opts.location, &csClient)

	stop := make(chan struct{})
	signalChannel := make(chan os.Signal, 1)
	signal.Notify(signalChannel, syscall.SIGINT, syscall.SIGTERM)
	go f.Run(ctx, stop)

	sig := <-signalChannel
	logger.Info(fmt.Sprintf("caught %s signal", sig))
	close(stop)

	f.Join()
	_ = otelShutdown(ctx)
	logger.Info(fmt.Sprintf("%s (%s) stopped", frontend.ProgramName, version.CommitSHA))

	return nil
}