Merge 0615a5e into 9eaa369

gcputil/gcputil.go

@@ -0,0 +1,103 @@
+// Package gcputil provides functions
+// that interact with various GCP platforms
+// such as getting GAE metadata and registering
+// stack driver monitoring
+package gcputil
+
+import (
+	"os"
+
+	"contrib.go.opencensus.io/exporter/stackdriver"
+	"contrib.go.opencensus.io/exporter/stackdriver/monitoredresource"
+	"go.opencensus.io/stats/view"
+	"go.opencensus.io/trace"
+)
+
+// RegisterOpenCensus will register
+// the tracing and metrics through
+// the stack driver exporter, if exists in the underlying platform.
+func RegisterOpenCensus(projectID string, onErr func(error)) error {
+	svcName, svcVersion := "", ""
+	if IsGAE() {
+		_, svcName, svcVersion = GetGAEInfo()
+	} else if n, v := os.Getenv("SERVICE_NAME"), os.Getenv("SERVICE_VERSION"); n != "" {
+		svcName, svcVersion = n, v
+	}
+	opts := SDExporterOptions(projectID, svcName, svcVersion, onErr)
+	if opts == nil {
+		return nil
+	}
+	return InitSDExporter(*opts)
+}
+
+// GoogleProjectID returns the GCP Project ID
+// that can be used to instantiate various
+// GCP clients such as Stack Driver.
+func GoogleProjectID() string {
+	return os.Getenv("GOOGLE_CLOUD_PROJECT")
+}
+
+// IsGAE tells you whether your program is running
+// within the App Engine platform.
+func IsGAE() bool {
+	return os.Getenv("GAE_DEPLOYMENT_ID") != ""
+}
+
+// GetGAEInfo returns the GCP Project ID,
+// the service, and the version of the application.
+func GetGAEInfo() (projectID, service, version string) {
+	return GoogleProjectID(),
+		os.Getenv("GAE_SERVICE"),
+		os.Getenv("GAE_VERSION")
+}
+
+// SDExporterOptions returns Stack Driver Options that you can pass directly
+// to the OpenCensus exporter or other libraries.
+func SDExporterOptions(projectID, service, version string, onErr func(err error)) *stackdriver.Options {
+	var mr monitoredresource.Interface
+	if m := monitoredresource.Autodetect(); m != nil {
+		mr = m
+	} else if IsGAE() {
+		mr = gaeInterface{
+			typ: "gae_app",
+			labels: map[string]string{
+				"project_id": projectID,
+			},
+		}
+	}
+	if mr == nil {
+		return nil
+	}
+
+	return &stackdriver.Options{
+		ProjectID:               projectID,
+		MonitoredResource:       mr,
+		OnError:                 onErr,
+		DefaultMonitoringLabels: &stackdriver.Labels{},
+		DefaultTraceAttributes: map[string]interface{}{
+			"service": service,
+			"version": version,
+		},
+	}
+}
+
+// InitSDExporter will initialize the OpenCensus tracing/metrics exporter
+func InitSDExporter(opts stackdriver.Options) error {
+	exporter, err := stackdriver.NewExporter(opts)
+	if err != nil {
+		return err
+	}
+	trace.RegisterExporter(exporter)
+	view.RegisterExporter(exporter)
+	return nil
+}
+
+// implements contrib.go.opencensus.io/exporter/stackdriver/monitoredresource.Interface
+type gaeInterface struct {
+	typ    string
+	labels map[string]string
+}
+
+func (g gaeInterface) MonitoredResource() (string, map[string]string) {
+	return g.typ, g.labels
+}

server/kit/kitserver.go

@@ -13,6 +13,7 @@ import (
 
 	"cloud.google.com/go/errorreporting"
 	sdpropagation "contrib.go.opencensus.io/exporter/stackdriver/propagation"
+	"github.com/NYTimes/gizmo/gcputil"
 	"github.com/go-kit/kit/log"
 	httptransport "github.com/go-kit/kit/transport/http"
 	grpc_middleware "github.com/grpc-ecosystem/go-grpc-middleware"
@@ -89,16 +90,20 @@ func NewServer(svc Service) *Server {
 		propr propagation.HTTPFormat
 	)
 
-	projectID := googleProjectID()
+	projectID := gcputil.GoogleProjectID()
 	var svcName, svcVersion string
-	if isGAE() {
-		_, svcName, svcVersion = getGAEInfo()
+	if gcputil.IsGAE() {
+		_, svcName, svcVersion = gcputil.GetGAEInfo()
 	} else if n, v := os.Getenv("SERVICE_NAME"), os.Getenv("SERVICE_VERSION"); n != "" {
 		svcName, svcVersion = n, v
 	}
 
-	if opt := sdExporterOptions(projectID, svcName, svcVersion, lg); opt != nil {
-		err = initSDExporter(*opt)
+	onErr := func(err error) {
+		lg.Log("error", err, "message", "tracing client encountered an error")
+	}
+
+	if opt := gcputil.SDExporterOptions(projectID, svcName, svcVersion, onErr); opt != nil {
+		err = gcputil.InitSDExporter(*opt)
 		if err != nil {
 			lg.Log("error", err,
 				"message", "unable to initiate error tracing exporter")

server/kit/log.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"os"
 
+	"github.com/NYTimes/gizmo/gcputil"
 	"github.com/go-kit/kit/log"
 	"github.com/go-kit/kit/transport/http"
 	"google.golang.org/grpc/metadata"
@@ -23,7 +24,7 @@ import (
 // If an empty string is provided, "gae_log" will be used in App Engine and "stdout" elsewhere.
 // For more information about to use of logID see the documentation here: https://cloud.google.com/logging/docs/reference/v2/rest/v2/LogEntry#FIELDS.log_name
 func NewLogger(ctx context.Context, logID string) (log.Logger, func() error, error) {
-	projectID, serviceID, svcVersion := getGAEInfo()
+	projectID, serviceID, svcVersion := gcputil.GetGAEInfo()
 	lg, cl, err := newStackdriverLogger(ctx, logID, projectID, serviceID, svcVersion)
 	// if Stackdriver logger was not able to find information about monitored resource it returns nil.
 	if err != nil {

server/kit/sd_log.go

@@ -5,29 +5,18 @@ import (
 	"encoding"
 	"encoding/json"
 	"fmt"
-	"os"
 	"reflect"
 	"strings"
 
 	"cloud.google.com/go/logging"
 	"contrib.go.opencensus.io/exporter/stackdriver/monitoredresource"
+	"github.com/NYTimes/gizmo/gcputil"
 	"github.com/go-kit/kit/log"
 	"github.com/go-kit/kit/log/level"
 	"github.com/pkg/errors"
 	"google.golang.org/genproto/googleapis/api/monitoredres"
 )
 
-// project, service, version
-func getGAEInfo() (string, string, string) {
-	return googleProjectID(),
-		os.Getenv("GAE_SERVICE"),
-		os.Getenv("GAE_VERSION")
-}
-
-func isGAE() bool {
-	return os.Getenv("GAE_DEPLOYMENT_ID") != ""
-}
-
 type sdLogger struct {
 	project string
 	monRes  *monitoredres.MonitoredResource
@@ -43,7 +32,7 @@ func newStackdriverLogger(ctx context.Context, logID, projectID, service, versio
 			"version_id": version,
 		},
 	}
-	if isGAE() {
+	if gcputil.IsGAE() {
 		resource.Type = "gae_app"
 		if logID == "" {
 			logID = "app_logs"