Pub/Sub: add note for high volume push requests (GoogleCloudPlatform#1567)

anguillanneuf · web-flow · commit 90aba8b343e8 · 2019-08-28T12:24:36.000-07:00
diff --git a/appengine-java8/pubsub/src/main/java/com/example/appengine/pubsub/PubSubAuthenticatedPush.java b/appengine-java8/pubsub/src/main/java/com/example/appengine/pubsub/PubSubAuthenticatedPush.java
@@ -71,6 +71,11 @@ public void doPost(HttpServletRequest req, HttpServletResponse resp)
 
     try {
       // Verify and decode the JWT.
+      // Note: For high volume push requests, it would save some network overhead
+      // if you verify the tokens offline by decoding them using Google's Public
+      // Cert; caching already seen tokens works best when a large volume of
+      // messsages have prompted a singple push server to handle them, in which
+      // case they would all share the same token for a limited time window.
       GoogleIdToken idToken = verifier.verify(authorization);
       messageRepository.saveToken(authorization);
       messageRepository.saveClaim(idToken.getPayload().toPrettyString());
