From 88ec3a575190c9282468c866bd4d6d9f2025453c Mon Sep 17 00:00:00 2001
From: Jon Chambers <jon@signal.org>
Date: Wed, 17 Jun 2020 11:25:13 -0400
Subject: [PATCH] Add a counter for dead letter events.

---
 .../textsecuregcm/websocket/DeadLetterHandler.java         | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/websocket/DeadLetterHandler.java b/service/src/main/java/org/whispersystems/textsecuregcm/websocket/DeadLetterHandler.java
index a82f0e583..0151fea18 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/websocket/DeadLetterHandler.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/websocket/DeadLetterHandler.java
@@ -1,6 +1,8 @@
 package org.whispersystems.textsecuregcm.websocket;
 
 import com.google.protobuf.InvalidProtocolBufferException;
+import io.micrometer.core.instrument.Counter;
+import io.micrometer.core.instrument.Metrics;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.whispersystems.dispatch.DispatchChannel;
@@ -8,12 +10,16 @@ import org.whispersystems.textsecuregcm.entities.MessageProtos.Envelope;
 import org.whispersystems.textsecuregcm.storage.MessagesManager;
 import org.whispersystems.textsecuregcm.storage.PubSubProtos.PubSubMessage;
 
+import static com.codahale.metrics.MetricRegistry.name;
+
 public class DeadLetterHandler implements DispatchChannel {
 
   private final Logger logger = LoggerFactory.getLogger(DeadLetterHandler.class);
 
   private final MessagesManager messagesManager;
 
+  private final Counter deadLetterCounter = Metrics.counter(name(getClass(), "deadLetterCounter"));
+
   public DeadLetterHandler(MessagesManager messagesManager) {
     this.messagesManager = messagesManager;
   }
@@ -22,6 +28,7 @@ public class DeadLetterHandler implements DispatchChannel {
   public void onDispatchMessage(String channel, byte[] data) {
     try {
       logger.info("Handling dead letter to: " + channel);
+      deadLetterCounter.increment();
 
       WebsocketAddress address       = new WebsocketAddress(channel);
       PubSubMessage    pubSubMessage = PubSubMessage.parseFrom(data);