Add websocket example and tests

Author: emily-shen

fixtures/helpers/index.ts

@@ -62,8 +62,8 @@ export class WranglerDevRunner {
     return this.urlPromise;
   }
 
-  async stop(containerId: string[]): Promise<void> {
-    for (const id of containerId) {
+  async stop(containerId?: string[]): Promise<void> {
+    for (const id of containerId ?? []) {
       await fetch(this.url + '/stop?id=' + id);
     }
     // give it a second to run the onStop hook before we kill the process

fixtures/websocket/Dockerfile

@@ -0,0 +1,12 @@
+# syntax=docker/dockerfile:1
+FROM node:22-alpine
+
+WORKDIR /usr/src/app
+
+COPY container_src/package.json package.json
+RUN npm install
+
+COPY container_src/server.js server.js
+
+EXPOSE 8080
+STOPSIGNAL SIGINT

fixtures/websocket/container_src/package.json

@@ -0,0 +1,6 @@
+{
+  "type": "module",
+  "dependencies": {
+    "ws": "^8.0.0"
+  }
+}

fixtures/websocket/container_src/server.js

@@ -0,0 +1,42 @@
+import { createServer } from "http";
+import { WebSocketServer } from 'ws';
+
+const server = createServer(function (req, res) {
+  if (req.url === '/error') {
+    res.writeHead(500, { "Content-Type": "text/plain" });
+    res.end("Internal server error");
+    return;
+  }
+  
+  res.writeHead(200, { "Content-Type": "text/plain" });
+  res.end(`Hello from WebSocket test container! process.env.MESSAGE: ${process.env.MESSAGE}`);
+});
+
+// Create WebSocket server
+const wss = new WebSocketServer({ server, path: '/ws' });
+
+wss.on('connection', function connection(ws, req) {
+  console.log('WebSocket connection established');
+  
+  ws.on('message', function message(data) {
+    console.log('WebSocket received:', data.toString());
+    // Echo the message back with container info
+    ws.send(`Echo from container: ${data.toString()} | MESSAGE: ${process.env.MESSAGE}`);
+  });
+  
+  ws.on('close', function close() {
+    console.log('WebSocket connection closed');
+  });
+  
+  // Send welcome message
+  ws.send(`WebSocket connected to container! MESSAGE: ${process.env.MESSAGE}`);
+});
+
+server.listen(8080, function () {
+  console.log(`WebSocket test server listening on port 8080`);
+});
+
+server.on("exit", () => {
+  console.log("WebSocket test server exiting");
+})
+