Instrument Go service with Stats and monitored resources. (GoogleClou…

…dPlatform#30)

added default views for stats  for http and grpc in Go services only.
added monitored resources for go.

src/checkoutservice/Gopkg.toml

@@ -31,7 +31,7 @@
 
 [[constraint]]
   name = "contrib.go.opencensus.io/exporter/stackdriver"
-  version = "0.5.0"
+  version = "0.6.0"
 
 [[constraint]]
   name = "github.com/golang/protobuf"

src/checkoutservice/main.go

@@ -26,11 +26,13 @@ import (
 	"contrib.go.opencensus.io/exporter/stackdriver"
 	"github.com/google/uuid"
 	"go.opencensus.io/plugin/ocgrpc"
+	"go.opencensus.io/stats/view"
 	"go.opencensus.io/trace"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 
+	"contrib.go.opencensus.io/exporter/stackdriver/monitoredresource"
 	pb "github.com/GoogleCloudPlatform/microservices-demo/src/checkoutservice/genproto"
 	money "github.com/GoogleCloudPlatform/microservices-demo/src/checkoutservice/money"
 )
@@ -78,17 +80,31 @@ func main() {
 	log.Fatal(srv.Serve(lis))
 }
 
+func initStats(exporter *stackdriver.Exporter) {
+	view.RegisterExporter(exporter)
+	if err := view.Register(ocgrpc.DefaultServerViews...); err != nil {
+		log.Printf("Error registering default server views")
+	} else {
+		log.Printf("Registered default server views");
+	}
+}
+
 func initTracing() {
 	// TODO(ahmetb) this method is duplicated in other microservices using Go
 	// since they are not sharing packages.
 	for i := 1; i <= 3; i++ {
-		exporter, err := stackdriver.NewExporter(stackdriver.Options{})
+		exporter, err := stackdriver.NewExporter(stackdriver.Options{
+			MonitoredResource: monitoredresource.Autodetect(),
+		})
 		if err != nil {
 			log.Printf("info: failed to initialize stackdriver exporter: %+v", err)
 		} else {
 			trace.RegisterExporter(exporter)
 			trace.ApplyConfig(trace.Config{DefaultSampler: trace.AlwaysSample()})
 			log.Print("registered stackdriver tracing")
+
+			// Register the views to collect server stats.
+			initStats(exporter)
 			return
 		}
 		d := time.Second * 10 * time.Duration(i)