add ready and liveness healthchecks and log dataset updates (#253)

* log dataset updates

* add readiness/liveness checks

* tweak update complete messages

Author: gfr10598

annotator.yaml

@@ -43,3 +43,9 @@ env_variables:
     # These should be substituted in the travis deployment script.
   RELEASE_TAG: ${TRAVIS_TAG}
   COMMIT_HASH: ${TRAVIS_COMMIT}
+
+liveness_check:
+  path: "/live"
+
+readiness_check:
+  path: "/ready"

handler/handler.go

@@ -31,17 +31,9 @@ const (
 func InitHandler() {
 	manager.MustUpdateDirectory()
 
-	// sets up any handlers that are needed, including url
-	// handlers and pubsub handlers
+	// sets up any handlers that are needed
 	http.HandleFunc("/annotate", Annotate)
 	http.HandleFunc("/batch_annotate", BatchAnnotate)
-
-	// DEPRECATED
-	// This code is disabled, to deal with a confusing pubsub subscription quota.
-	// It is no longer needed because Ya implemented an external cron trigger.
-	// This listens for pubsub messages about new downloader files, and loads them
-	// when they become available.
-	// go waitForDownloaderMessages()
 }
 
 // Annotate is a URL handler that looks up IP address and puts

main.go

@@ -53,6 +53,19 @@ func updateMaxmindDatasets(w http.ResponseWriter, r *http.Request) {
 	w.Write([]byte("OK"))
 }
 
+func live(w http.ResponseWriter, r *http.Request) {
+	w.WriteHeader(http.StatusOK)
+}
+
+func ready(w http.ResponseWriter, r *http.Request) {
+	ann, _ := manager.GetAnnotator(time.Now())
+	if ann == nil {
+		w.WriteHeader(http.StatusServiceUnavailable)
+		return
+	}
+	w.WriteHeader(http.StatusOK)
+}
+
 func init() {
 	// Always prepend the filename and line number.
 	log.SetFlags(log.LstdFlags | log.Lshortfile)
@@ -72,6 +85,8 @@ func main() {
 
 	http.HandleFunc("/status", Status)
 	http.HandleFunc("/updateDatasets", updateMaxmindDatasets)
+	http.HandleFunc("/ready", ready)
+	http.HandleFunc("/live", live)
 
 	handler.InitHandler()
 	log.Print("Listening on port 8080")

manager/manager.go

@@ -130,30 +130,38 @@ func (bldr *listBuilder) update() error {
 
 	var errV4, errV6, errG2, errAsnV4, errAsnV6 error
 
+	log.Println("Updating dataset directory")
 	wg := sync.WaitGroup{}
 	wg.Add(5)
 	go func() {
 		errV4 = bldr.legacyV4.UpdateCache()
+		log.Println("Legacy V4 loading done.")
 		wg.Done()
 	}()
 	go func() {
 		errV6 = bldr.legacyV6.UpdateCache()
+		log.Println("Legacy V6 loading done.")
 		wg.Done()
 	}()
 	go func() {
 		errG2 = bldr.geolite2.UpdateCache()
+		log.Println("Geolite2 loading done.")
 		wg.Done()
 	}()
 	go func() {
 		errAsnV4 = bldr.asnV4.UpdateCache()
+		log.Println("ASN V4 loading done.")
 		wg.Done()
 	}()
 	go func() {
 		errAsnV6 = bldr.asnV6.UpdateCache()
+		log.Println("ASN V6 loading done.")
 		wg.Done()
 	}()
 	wg.Wait()
 
+	log.Println("Dataset update complete.")
+
 	if errV4 != nil {
 		return errV4
 	}