feat: display browser runtime errors in the terminal

packages/core/src/client/hmr.ts

@@ -1,4 +1,8 @@
-import type { SocketMessage } from '../server/socketServer';
+import type {
+  ClientMessage,
+  ClientMessageRuntimeError,
+  SocketMessage,
+} from '../server/socketServer';
 import type { NormalizedClientConfig } from '../types';
 
 const config: NormalizedClientConfig = RSBUILD_CLIENT_CONFIG;
@@ -150,6 +154,13 @@ let socket: WebSocket | null = null;
 let reconnectCount = 0;
 let pingIntervalId: ReturnType<typeof setInterval>;
 
+const isSocketReady = () => socket && socket.readyState === socket.OPEN;
+const socketSend = (data: ClientMessage) => {
+  if (isSocketReady()) {
+    socket!.send(JSON.stringify(data));
+  }
+};
+
 function onOpen() {
   // Notify users that the WebSocket has successfully connected.
   console.info('[rsbuild] WebSocket connected.');
@@ -160,10 +171,15 @@ function onOpen() {
   // To prevent WebSocket timeouts caused by proxies (e.g., nginx, docker),
   // send a periodic ping message to keep the connection alive.
   pingIntervalId = setInterval(() => {
-    if (socket && socket.readyState === socket.OPEN) {
-      socket.send(JSON.stringify({ type: 'ping' }));
-    }
+    socketSend({ type: 'ping' });
   }, 30000);
+
+  if (errorMessages.length) {
+    errorMessages.forEach((message) => {
+      socketSend(message);
+    });
+    errorMessages.length = 0;
+  }
 }
 
 function onMessage(e: MessageEvent<string>) {
@@ -214,7 +230,7 @@ function onClose() {
   setTimeout(connect, 1000 * 1.5 ** reconnectCount);
 }
 
-function onError() {
+function onSocketError() {
   if (formatURL() !== formatURL(true)) {
     console.error(
       '[rsbuild] WebSocket connection failed. Trying direct connection fallback.',
@@ -225,6 +241,20 @@ function onError() {
   }
 }
 
+const errorMessages: ClientMessageRuntimeError[] = [];
+
+function onRuntimeError(event: ErrorEvent) {
+  const message: ClientMessageRuntimeError = {
+    type: 'runtime-error',
+    message: event.message,
+  };
+  if (isSocketReady()) {
+    socketSend(message);
+  } else {
+    errorMessages.push(message);
+  }
+}
+
 // Establishing a WebSocket connection with the server.
 function connect(fallback = false) {
   if (reconnectCount === 0) {
@@ -240,7 +270,7 @@ function connect(fallback = false) {
   socket.addEventListener('message', onMessage);
   // Handle errors
   if (!fallback) {
-    socket.addEventListener('error', onError);
+    socket.addEventListener('error', onSocketError);
   }
 }
 
@@ -250,7 +280,7 @@ function removeListeners() {
     socket.removeEventListener('open', onOpen);
     socket.removeEventListener('close', onClose);
     socket.removeEventListener('message', onMessage);
-    socket.removeEventListener('error', onError);
+    socket.removeEventListener('error', onSocketError);
   }
 }
 
@@ -260,4 +290,8 @@ function reloadPage() {
   }
 }
 
+if (typeof window !== 'undefined') {
+  window.addEventListener('error', onRuntimeError);
+}
+
 connect();

packages/core/src/server/socketServer.ts

@@ -2,6 +2,7 @@ import type { IncomingMessage } from 'node:http';
 import type { Socket } from 'node:net';
 import type Ws from '../../compiled/ws/index.js';
 import {
+  color,
   getAllStatsErrors,
   getAllStatsWarnings,
   getStatsOptions,
@@ -44,13 +45,24 @@ export type SocketMessageErrors = {
   data: { text: string[]; html: string };
 };
 
+export type ClientMessageRuntimeError = {
+  type: 'runtime-error';
+  message: string;
+};
+
+export type ClientMessagePing = {
+  type: 'ping';
+};
+
 export type SocketMessage =
   | SocketMessageOk
   | SocketMessageStaticChanged
   | SocketMessageHash
   | SocketMessageWarnings
   | SocketMessageErrors;
 
+export type ClientMessage = ClientMessagePing | ClientMessageRuntimeError;
+
 const parseQueryString = (req: IncomingMessage) => {
   const queryStr = req.url ? req.url.split('?')[1] : '';
   return queryStr ? Object.fromEntries(new URLSearchParams(queryStr)) : {};
@@ -247,6 +259,22 @@ export class SocketServer {
       socket.isAlive = true;
     });
 
+    socket.on('message', (data) => {
+      try {
+        const message: ClientMessage = JSON.parse(
+          // eslint-disable-next-line @typescript-eslint/no-base-to-string
+          typeof data === 'string' ? data : data.toString(),
+        );
+
+        // Handle runtime errors from browser
+        if (message.type === 'runtime-error') {
+          logger.error(
+            `${color.cyan('[browser]')} ${color.red(message.message)}`,
+          );
+        }
+      } catch {}
+    });
+
     let sockets = this.socketsMap.get(token);
     if (!sockets) {
       sockets = new Set();