Add Google Analytics reporting in place of existing custom reporting (#2015)

Replacing the older analytics with a new Google Analytics based mechanism.

pkg/router/analytics.go

@@ -1,69 +0,0 @@
-package router
-
-import (
-	"bytes"
-	"encoding/json"
-	"net/http"
-	"os"
-	"sync/atomic"
-	"time"
-
-	"github.com/dchest/uniuri"
-)
-
-type (
-	// Analytics helps exporting usage metrics
-	Analytics struct {
-		id  string
-		url string
-	}
-
-	// AnalyticsData is the data exported as usage metrics
-	AnalyticsData struct {
-		ID                string `json:"ID"`
-		FunctionCallCount uint64 `json:"FunctionCallCount"`
-	}
-)
-
-// MakeAnalytics returns a new instance of Analytics if url or
-// 'ANALYTICS_URL' environment variable is set; nil otherwise
-func MakeAnalytics(url string) *Analytics {
-	if len(url) == 0 {
-		url = os.Getenv("ANALYTICS_URL")
-		if len(url) == 0 {
-			return nil
-		}
-	}
-
-	a := &Analytics{
-		url: url,
-		id:  uniuri.NewLen(8),
-	}
-	go a.run()
-	return a
-}
-
-func (a *Analytics) gatherData() *AnalyticsData {
-	return &AnalyticsData{
-		FunctionCallCount: atomic.LoadUint64(&globalFunctionCallCount),
-	}
-}
-
-func (a *Analytics) run() {
-	ticker := time.NewTicker(24 * time.Hour)
-	for range ticker.C {
-		msg := a.gatherData()
-		msg.ID = a.id
-
-		msgbytes, err := json.Marshal(*msg)
-		if err != nil {
-			continue
-		}
-
-		resp, _ := http.Post(a.url, "application/json", bytes.NewReader(msgbytes))
-		if resp != nil {
-			// close response body to prevent resources leak
-			resp.Body.Close()
-		}
-	}
-}

pkg/router/router.go

@@ -119,8 +119,6 @@ func serveMetric(logger *zap.Logger) {
 
 // Start starts a router
 func Start(logger *zap.Logger, port int, executorURL string) {
-	_ = MakeAnalytics("")
-
 	fmap := makeFunctionServiceMap(logger, time.Minute)
 
 	fissionClient, kubeClient, _, _, err := crd.MakeFissionClient()