hub-worker

TogetherJS hub, on Cloudflare Workers

A port of ../hub/server.js to Cloudflare Workers + Durable Objects. Same protocol, same behavior, no server to babysit:

• GET /status → 200 OK health check.
• WebSocket connections to /hub/<roomId> join a room; every message from one peer is relayed verbatim to every other peer in the same room. Setting "server-echo": true on a message also sends it back to the sender.
• On connect, the server sends {"type": "init-connection", "peerCount": N} where N is the number of peers already in the room.
• GET /findroom?prefix=CHARS&max=NUM → {"name": "<prefix>__<id>"}, for clients using TogetherJSConfig.findRoom. Picks an existing prefix__* room with fewer than max peers (least-populated first, random tie-break), or mints a new prefix__<10-char id> if none qualify — same algorithm as the old server (hub/server.js:167-194).

Each room is one Durable Object instance (src/room.ts), addressed by name from the room id (src/index.ts) — this mirrors the original's in-memory allConnections[id] grouping, just with Cloudflare managing the instance lifecycle instead of a single long-running Node process. Rooms use the WebSocket Hibernation API, so an idle room's Durable Object can be evicted from memory between messages at no cost.

/findroom is backed by a second, singleton Durable Object (src/registry.ts, Registry) that tracks peer counts per room — a single Room instance only knows about its own peers, not siblings sharing a prefix. Room reports its peer count to the registry on connect/disconnect, but only for rooms whose id contains "__" (i.e. rooms that came from /findroom in the first place), so ordinary share-link sessions never touch the registry.

Not ported: the Hixie-76 (pre-RFC6455) websocket compat shim, /server-source, and /load stats.

Setup

npm install

Local dev

npm run dev

Runs a local server via wrangler dev (prints the URL, typically http://localhost:8787). Point TogetherJSConfig_hubBase at it to test against a local build.

Deploy

npm run deploy

Requires a Cloudflare account (wrangler will prompt you to log in on first use). Deploys to your account's *.workers.dev subdomain by default; add a routes entry in wrangler.toml to use a custom domain instead. No credit card is required — Durable Objects with the SQLite storage backend (configured in wrangler.toml) run on the Workers Free plan.

After deploying, point TogetherJS at the printed URL:

TogetherJSConfig_hubBase = "https://togetherjs-hub.<your-subdomain>.workers.dev";