use setTimeout for heartbeat in favour of first random interval

src/ws/heartbeat.ts

@@ -14,28 +14,44 @@ export function heartbeat(shardId: number, interval: number) {
   shard.heartbeat.lastSentAt = Date.now();
   shard.heartbeat.interval = interval;
 
-  shard.heartbeat.intervalId = setInterval(() => {
-    ws.log("DEBUG", `Running setInterval in heartbeat file.`);
-    const currentShard = ws.shards.get(shardId);
-    if (!currentShard) return;
-
-    ws.log("HEARTBEATING", { shardId, shard: currentShard });
-
-    if (
-      currentShard.ws.readyState === WebSocket.CLOSED ||
-      !currentShard.heartbeat.keepAlive
-    ) {
-      ws.log("HEARTBEATING_CLOSED", { shardId, shard: currentShard });
-
-      // STOP THE HEARTBEAT
-      return clearInterval(currentShard.heartbeat.intervalId);
-    }
-
-    if (currentShard.ws.readyState !== WebSocket.OPEN) return;
-
-    currentShard.ws.send(JSON.stringify({
-      op: DiscordGatewayOpcodes.Heartbeat,
-      d: currentShard.previousSequenceNumber,
-    }));
-  }, interval);
+  // First heartbeat should be sent bevore
+  shard.heartbeat.timeoutId = setTimeout(
+    () => sendHeartbeat(shardId),
+    Math.floor(shard.heartbeat.interval * Math.random()),
+  );
+}
+
+function sendHeartbeat(shardId: number) {
+  ws.log("DEBUG", `Running setInterval in heartbeat file.`);
+  const currentShard = ws.shards.get(shardId);
+  if (!currentShard) return;
+
+  ws.log("HEARTBEATING", { shardId, shard: currentShard });
+
+  if (
+    currentShard.ws.readyState === WebSocket.CLOSED ||
+    !currentShard.heartbeat.keepAlive
+  ) {
+    ws.log("HEARTBEATING_CLOSED", { shardId, shard: currentShard });
+
+    // STOP THE HEARTBEAT
+    return;
+  }
+
+  if (currentShard.ws.readyState !== WebSocket.OPEN) {
+    currentShard.heartbeat.timeoutId = setTimeout(
+      () => sendHeartbeat(shardId),
+      currentShard.heartbeat.interval,
+    );
+  }
+
+  currentShard.ws.send(JSON.stringify({
+    op: DiscordGatewayOpcodes.Heartbeat,
+    d: currentShard.previousSequenceNumber,
+  }));
+
+  currentShard.heartbeat.timeoutId = setTimeout(
+    () => sendHeartbeat(shardId),
+    currentShard.heartbeat.interval,
+  );
 }

src/ws/identify.ts

@@ -7,7 +7,7 @@ export async function identify(shardId: number, maxShards: number) {
   // Need to clear the old heartbeat interval
   const oldShard = ws.shards.get(shardId);
   if (oldShard) {
-    clearInterval(oldShard.heartbeat.intervalId);
+    clearTimeout(oldShard.heartbeat.timeoutId);
   }
 
   // CREATE A SHARD
@@ -29,7 +29,7 @@ export async function identify(shardId: number, maxShards: number) {
       acknowledged: false,
       keepAlive: false,
       interval: 0,
-      intervalId: 0,
+      timeoutId: 0,
     },
     queue: [],
     processingQueue: false,

src/ws/ws.ts

@@ -138,7 +138,7 @@ export interface DiscordenoShard {
     /** The interval between heartbeats requested by discord. */
     interval: number;
     /** The id of the interval, useful for stopping the interval if ws closed. */
-    intervalId: number;
+    timeoutId: number;
   };
   /** The items/requestst that are in queue to be sent to this shard websocket. */
   queue: WebSocketRequest[];

tests/ws/ws_close.ts

@@ -7,7 +7,7 @@ Deno.test({
   name: "[ws] Close all shards manually.",
   async fn() {
     ws.shards.forEach((shard) => {
-      clearInterval(shard.heartbeat.intervalId);
+      clearTimeout(shard.heartbeat.timeoutId);
       shard.ws.close(3064, "Discordeno Testing Finished! Do Not RESUME!");
     });