Add collab fix to next config

Cherry pick fix

Author: WZWren

peerprep/components/questionpage/CollabEditor.tsx

@@ -77,8 +77,8 @@ export default function CollabEditor({ question, roomID, authToken }: Props) {
 
     console.log("Yep");
 
-    const newSocket = new WebSocket(`${process.env.NEXT_PUBLIC_COLLAB}/ws?roomID=${roomID}`);
-    
+    const newSocket = new WebSocket(`/api/proxy?roomID=${roomID}`);
+
     newSocket.onopen = () => {
       console.log("WebSocket connection established");
       setconnected(true);

peerprep/next.config.js

@@ -1,4 +1,15 @@
 /** @type {import('next').NextConfig} */
 const nextConfig = {}
 
-module.exports = nextConfig
+module.exports = {
+  async rewrites() {
+    return [
+      {
+        source: '/api/proxy', // client connects to api/proxy
+        // by default we expect NEXT_PUBLIC_COLLAB to be http://collab:4000.
+        // double check this before using this.
+        destination: `${process.env.NEXT_PUBLIC_COLLAB}/ws`,
+      }
+    ]
+  }
+}