fix(WebSocketShard): retry on 5xx error

Author: didinele

packages/ws/src/ws/WebSocketShard.ts

@@ -1,5 +1,6 @@
 import { Buffer } from 'node:buffer';
 import { once } from 'node:events';
+import type { IncomingMessage } from 'node:http';
 import { clearInterval, clearTimeout, setInterval, setTimeout } from 'node:timers';
 import { setTimeout as sleep } from 'node:timers/promises';
 import { URLSearchParams } from 'node:url';
@@ -252,21 +253,25 @@ export class WebSocketShard extends AsyncEventEmitter<WebSocketShardEventsMap> {
 
 		connection.binaryType = 'arraybuffer';
 
-		connection.onmessage = (event) => {
-			void this.onMessage(event.data, event.data instanceof ArrayBuffer);
-		};
+		connection.on('message', (event) => {
+			void this.onMessage(event, event instanceof ArrayBuffer);
+		});
 
-		connection.onerror = (event) => {
-			this.onError(event.error);
-		};
+		connection.on('error', (event) => {
+			this.onError(event);
+		});
 
-		connection.onclose = (event) => {
-			void this.onClose(event.code);
-		};
+		connection.on('close', (code) => {
+			void this.onClose(code);
+		});
 
-		connection.onopen = () => {
+		connection.on('open', () => {
 			this.sendRateLimitState = getInitialSendRateLimitState();
-		};
+		});
+
+		connection.on('unexpected-response', (_, response) => {
+			this.onUnexpectedResponse(response);
+		});
 
 		this.connection = connection;
 
@@ -800,6 +805,19 @@ export class WebSocketShard extends AsyncEventEmitter<WebSocketShardEventsMap> {
 		this.emit(WebSocketShardEvents.Error, error);
 	}
 
+	private onUnexpectedResponse(response: IncomingMessage) {
+		if (response.statusCode && response.statusCode >= 500) {
+			this.debug(['Received a 5xx response from the server, retrying']);
+			this.failedToConnectDueToNetworkError = true;
+			return;
+		}
+
+		this.emit(
+			WebSocketShardEvents.Error,
+			new Error(`Unexpected response from the server: ${response.statusCode ?? 'unknown'}`),
+		);
+	}
+
 	private async onClose(code: number) {
 		this.emit(WebSocketShardEvents.Closed, code);