From 4557eaa141360078ee45e25400a811ca74f85988 Mon Sep 17 00:00:00 2001
From: Sidd <iProdigy@users.noreply.github.com>
Date: Thu, 3 Mar 2022 23:43:39 -0800
Subject: [PATCH 1/2] feat: track chat socket latency

---
 .../com/github/twitch4j/chat/ITwitchChat.java |  5 ++++
 .../com/github/twitch4j/chat/TwitchChat.java  | 26 +++++++++++++++++++
 .../chat/TwitchChatConnectionPool.java        | 14 ++++++++++
 3 files changed, 45 insertions(+)

diff --git a/chat/src/main/java/com/github/twitch4j/chat/ITwitchChat.java b/chat/src/main/java/com/github/twitch4j/chat/ITwitchChat.java
index 9f957ce1e..3f60a7d71 100644
--- a/chat/src/main/java/com/github/twitch4j/chat/ITwitchChat.java
+++ b/chat/src/main/java/com/github/twitch4j/chat/ITwitchChat.java
@@ -79,6 +79,11 @@ default boolean sendMessage(String channel, String message, @Unofficial String n
     @Override
     void close();
 
+    /**
+     * @return the most recently measured round-trip latency for the socket(s)
+     */
+    long getLatency();
+
     /**
      * @return cached mappings of channel ids to names
      */
diff --git a/chat/src/main/java/com/github/twitch4j/chat/TwitchChat.java b/chat/src/main/java/com/github/twitch4j/chat/TwitchChat.java
index 3c1ddc4f5..b4461a03e 100644
--- a/chat/src/main/java/com/github/twitch4j/chat/TwitchChat.java
+++ b/chat/src/main/java/com/github/twitch4j/chat/TwitchChat.java
@@ -53,6 +53,7 @@
 import java.util.concurrent.ThreadLocalRandom;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicLong;
 import java.util.concurrent.locks.ReentrantLock;
 import java.util.function.Consumer;
 
@@ -237,6 +238,14 @@ public class TwitchChat implements ITwitchChat {
      */
     private final int wsPingPeriod;
 
+    /**
+     * Tracks the timestamp of the last outbound ping
+     */
+    protected final AtomicLong lastPing = new AtomicLong();
+
+    @Getter
+    protected volatile long latency = -1L;
+
     /**
      * Cache of recent number of join attempts for each channel
      */
@@ -625,6 +634,23 @@ public void onDisconnected(WebSocket websocket,
                         log.info("Disconnected from Twitch IRC (WebSocket)!");
                     }
                 }
+
+                @Override
+                public void onFrameSent(WebSocket websocket, WebSocketFrame frame) {
+                    if (frame != null && frame.isPingFrame()) {
+                        lastPing.compareAndSet(0L, System.currentTimeMillis());
+                    }
+                }
+
+                @Override
+                public void onPongFrame(WebSocket websocket, WebSocketFrame frame) {
+                    final long last = lastPing.getAndSet(0L);
+                    if (last > 0) {
+                        latency = System.currentTimeMillis() - last;
+                        log.trace("TwitchChat: Round-trip socket latency recorded at {} ms.", latency);
+                    }
+                }
+
             });
 
         } catch (Exception ex) {
diff --git a/chat/src/main/java/com/github/twitch4j/chat/TwitchChatConnectionPool.java b/chat/src/main/java/com/github/twitch4j/chat/TwitchChatConnectionPool.java
index e7810abff..9564e99f7 100644
--- a/chat/src/main/java/com/github/twitch4j/chat/TwitchChatConnectionPool.java
+++ b/chat/src/main/java/com/github/twitch4j/chat/TwitchChatConnectionPool.java
@@ -278,6 +278,20 @@ protected void disposeConnection(TwitchChat connection) {
         connection.close();
     }
 
+    @Override
+    public long getLatency() {
+        long sum = 0;
+        int count = 0;
+        for (TwitchChat connection : getConnections()) {
+            final long latency = connection.getLatency();
+            if (latency > 0) {
+                sum += latency;
+                count++;
+            }
+        }
+        return count > 0 ? sum / count : -1L;
+    }
+
     /**
      * Note: this map does not dynamically update unlike {@link TwitchChat#getChannelIdToChannelName()}
      * <p>

From a7858075e9b928d92d57713c5cad8cccc1bab10b Mon Sep 17 00:00:00 2001
From: Sidd <iProdigy@users.noreply.github.com>
Date: Thu, 3 Mar 2022 23:56:01 -0800
Subject: [PATCH 2/2] docs: clarify units of ITwitchChat#getLatency

---
 chat/src/main/java/com/github/twitch4j/chat/ITwitchChat.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/chat/src/main/java/com/github/twitch4j/chat/ITwitchChat.java b/chat/src/main/java/com/github/twitch4j/chat/ITwitchChat.java
index 3f60a7d71..b71ab7f6f 100644
--- a/chat/src/main/java/com/github/twitch4j/chat/ITwitchChat.java
+++ b/chat/src/main/java/com/github/twitch4j/chat/ITwitchChat.java
@@ -80,7 +80,7 @@ default boolean sendMessage(String channel, String message, @Unofficial String n
     void close();
 
     /**
-     * @return the most recently measured round-trip latency for the socket(s)
+     * @return the most recently measured round-trip latency for the socket(s) in milliseconds, or -1 if unknown
      */
     long getLatency();