Fix WebSocket connection in dev mode (bun run dev)#7
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Vite's http-proxy cannot relay Bun.serve's WebSocket upgrade (101) response, so the /ws proxy silently times out and terminals never connect under `bun run dev` (broken since the initial commit). Connect the terminal WebSocket directly to the backend in dev instead of through the proxy, and remove the non-functional /ws proxy entry. Production/single-server mode is unchanged (the backend serves the client, so window.location.host already points at it). The backend port is configurable via VITE_BACKEND_PORT (defaults 6968).
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Re-trigger cubic
In dev the client connects directly to the plain-HTTP Bun backend, which has no TLS listener. Deriving the WebSocket protocol from the page meant an HTTPS-served dev page produced a wss:// URL that failed the TLS handshake. Always use ws:// for the direct dev connection; production still mirrors the page protocol and reuses the current host. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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1 issue found across 1 file (changes from recent commits).
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Re-trigger cubic
Forcing ws:// would be blocked by the browser's mixed-content policy when the dev page is served over HTTPS. Mirror the page protocol instead: the default HTTP dev page still yields ws:// (works against the plain backend), while an HTTPS dev page yields wss:// so the browser does not block it. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Problem
When running the project with
bun run dev, agent terminals never connect — you can't type into them and no output appears. This affects anyone developing against the repo (as opposed to the published single-serveropenuicommand, which works fine).Root cause
In dev, the frontend runs on Vite (
6969) and proxies to the Bun backend (6968). The HTTP/apiproxy works, but the/wsproxy does not: Vite forwards the upgrade and Bun accepts it (the backend logs[ws] Connected), but Vite's underlyinghttp-proxycannot relayBun.serve's101 Switching Protocolsresponse back to the browser. The socket never opens and the connection silently times out.This is a known incompatibility between Vite's
http-proxyandBun.serveWebSockets — not specific to any agent.Fix
client/src/components/Terminal.tsx— in dev, connect the terminal WebSocket directly to the backend (window.location.hostname+ backend port) instead of through the Vite proxy. The backend port is configurable viaVITE_BACKEND_PORT(defaults to6968). Production/single-server mode is unchanged: there the backend serves the built client itself, sowindow.location.hostalready points at the backend.client/vite.config.ts— remove the non-functional/wsproxy entry (with a comment explaining why). The/apiproxy is untouched.The backend performs no Origin check on upgrade, so the cross-port WebSocket from the dev page is accepted.
Verification
With the fix and
bun run devrunning:/api.Origin: http://localhost:6969header.ws OPENand command output received ✓.Terminals now work in dev mode without falling back to single-server/production mode.
Notes
+10 / −5. No behavior change in production.Summary by cubic
Fixes terminal WebSocket connections in dev by bypassing Vite’s proxy and connecting directly to the Bun backend. In dev, mirror the page protocol (ws/wss) to satisfy browser mixed-content rules; production/single-server is unchanged.
client/src/components/Terminal.tsx, in dev connect directly to${protocol}//${window.location.hostname}:${<VITE_BACKEND_PORT|6968>}/wswhereprotocolmirrors the page; production reuses the current host and protocol.client/vite.config.ts, remove the non-functional/wsproxy (keep/api), since Vite’shttp-proxycan’t relayBun.serve’s upgrade response.Written for commit 9076c4b. Summary will update on new commits.