From 7b17e0582682addb4b32cbb00729c087f8b241dc Mon Sep 17 00:00:00 2001
From: "Claude Opus 4.8" <opus-4-8@waidele.info>
Date: Wed, 8 Jul 2026 22:34:01 +0200
Subject: [PATCH] Fix e2e static server crashing on an abruptly-dropped collab
 WebSocket (#38)
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Root cause of the CI-only Auth-e2e failure (found in the runner log): the
offline pack started with `connect ECONNREFUSED :5173` — the e2e static web
server had already exited. Its `/collab` WebSocket proxy attached an 'error'
handler to the upstream socket but not to the client socket, so a WebSocket
dropped abruptly (a context closing at the end of the collab pack, or the
offline toggle) raised an unhandled 'error' → uncaught exception → the whole
test server crashed, failing the next pack. It only reproduced on the CI
runner (Linux/Node 22 emits 'error'; local macOS/Node 26 emitted 'close').

Handle 'error' on the client socket too, and add a last-resort
`uncaughtException` guard so this throwaway test server can never be taken
down mid-run by a stray socket error. Verified locally by running the collab
and offline packs back-to-back against a single server process.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PGdhRiwU1WRL4XxJfZYipY
---
 scripts/e2e-static-server.mjs | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/scripts/e2e-static-server.mjs b/scripts/e2e-static-server.mjs
index 6ea4365..45fb0b3 100644
--- a/scripts/e2e-static-server.mjs
+++ b/scripts/e2e-static-server.mjs
@@ -80,6 +80,11 @@ server.on('upgrade', (req, socket, head) => {
     socket.destroy();
     return;
   }
+  // A WebSocket that is dropped abruptly (e.g. a test toggling the browser
+  // offline, or a context closing) emits 'error' on these sockets. Without a
+  // listener that becomes an uncaught exception that would crash this server —
+  // so always handle it and just tear the pair down.
+  socket.on('error', () => socket.destroy());
   const upstream = httpRequest({
     hostname: COLLAB_TARGET.hostname,
     port: COLLAB_TARGET.port,
@@ -88,6 +93,7 @@ server.on('upgrade', (req, socket, head) => {
     headers: { ...req.headers, host: `${COLLAB_TARGET.hostname}:${COLLAB_TARGET.port}` },
   });
   upstream.on('upgrade', (upstreamRes, upstreamSocket, upstreamHead) => {
+    upstreamSocket.on('error', () => socket.destroy());
     const statusLine = `HTTP/1.1 ${upstreamRes.statusCode} ${upstreamRes.statusMessage}\r\n`;
     const headerLines = Object.entries(upstreamRes.headers)
       .map(([key, value]) => `${key}: ${value}`)
@@ -96,13 +102,18 @@ server.on('upgrade', (req, socket, head) => {
     if (upstreamHead?.length) socket.write(upstreamHead);
     upstreamSocket.pipe(socket);
     socket.pipe(upstreamSocket);
-    upstreamSocket.on('error', () => socket.destroy());
   });
   upstream.on('error', () => socket.destroy());
   if (head?.length) upstream.write(head);
   upstream.end();
 });
 
+// Last-resort guard: this is a throwaway test server, so a stray socket error
+// must never take it down mid-run and fail an unrelated later test pack.
+process.on('uncaughtException', (error) => {
+  console.error('e2e static server: ignored uncaught error:', error?.message ?? error);
+});
+
 server.listen(PORT, () =>
   console.log(
     `e2e static server on :${PORT} → api ${API_TARGET.href} collab ${COLLAB_TARGET.href}`,