Function startOpenCensus

gcp/observability/opencensus.go:124–158

This method accepts config and exporter; the exporter argument is exposed to assist unit testing of the OpenCensus behavior.

(config *config)

// This method accepts config and exporter; the exporter argument is exposed to
// assist unit testing of the OpenCensus behavior.
func startOpenCensus(config *config) error {
	// If both tracing and metrics are disabled, there's no point inject default
	// StatsHandler.
	if config == nil || (config.CloudTrace == nil && config.CloudMonitoring == nil) {
		return nil
	}

	var err error
	exporter, err = newExporter(config)
	if err != nil {
		return err
	}

	var to opencensus.TraceOptions
	if config.CloudTrace != nil {
		to.TS = trace.ProbabilitySampler(config.CloudTrace.SamplingRate)
		trace.RegisterExporter(exporter.(trace.Exporter))
		logger.Infof("Start collecting and exporting trace spans with global_trace_sampling_rate=%.2f", config.CloudTrace.SamplingRate)
	}

	if config.CloudMonitoring != nil {
		if err := view.Register(defaultViews...); err != nil {
			return fmt.Errorf("failed to register observability views: %v", err)
		}
		view.SetReportingPeriod(defaultMetricsReportingInterval)
		view.RegisterExporter(exporter.(view.Exporter))
		logger.Infof("Start collecting and exporting metrics")
	}

	internal.AddGlobalServerOptions.(func(opt ...grpc.ServerOption))(opencensus.ServerOption(to))
	internal.AddGlobalDialOptions.(func(opt ...grpc.DialOption))(opencensus.DialOption(to))
	logger.Infof("Enabled OpenCensus StatsHandlers for clients and servers")

	return nil
}

// stopOpenCensus flushes the exporter's and cleans up globals across all
// packages if exporter was created.