Files
clawtap/server/transport/websocket-transport.ts
T

88 lines
2.9 KiB
TypeScript

import { EventEmitter } from 'events';
import { WebSocketServer } from 'ws';
import type WebSocket from 'ws';
import type { Server as HttpServer } from 'http';
import type { Server as HttpsServer } from 'https';
import { verifyWebSocketToken } from '../auth.js';
import { WebSocketConnection } from './websocket-connection.js';
import type { ClientConnection } from './client-connection.js';
import type { ClientMessage } from '../types/messages.js';
/**
* WebSocketTransport — manages the WebSocket server lifecycle.
*
* Emits:
* 'connection' (conn: ClientConnection) — new authenticated client connected
* 'message' (conn: ClientConnection, msg: ClientMessage) — parsed message from client
*/
export class WebSocketTransport extends EventEmitter {
private wss: WebSocketServer | null = null;
private pingInterval: ReturnType<typeof setInterval> | null = null;
// Tracks whether each WS responded to the last ping. Initialized true so a
// connection is never terminated before it has a chance to respond.
private alive = new WeakMap<WebSocket, boolean>();
/** Create WebSocketServer on /ws path with JWT verification and ping/pong keepalive. */
setup(server: HttpServer | HttpsServer): void {
this.wss = new WebSocketServer({
server,
path: '/ws',
verifyClient: ({ req }, cb) => {
const url = new URL(req.url!, `http://${req.headers.host}`);
const token = url.searchParams.get('token');
if (!token || !verifyWebSocketToken(token)) {
cb(false, 401, 'Unauthorized');
return;
}
cb(true);
},
});
this.wss.on('connection', (ws: WebSocket) => {
this.alive.set(ws, true);
ws.on('pong', () => this.alive.set(ws, true));
const conn = new WebSocketConnection(ws);
this.emit('connection', conn);
ws.on('message', (raw: Buffer | ArrayBuffer | Buffer[]) => {
let msg: ClientMessage;
try {
msg = JSON.parse(raw.toString()) as ClientMessage;
} catch {
conn.send({ type: 'error', error: 'Invalid JSON' });
return;
}
this.emit('message', conn, msg);
});
});
// Ping/pong keepalive every 30s — terminate connections that miss a pong.
this.pingInterval = setInterval(() => {
if (!this.wss) return;
for (const ws of this.wss.clients) {
if (!this.alive.get(ws)) {
ws.terminate(); // no pong since last ping — dead connection
continue;
}
this.alive.set(ws, false);
if (ws.readyState === 1) ws.ping();
}
}, 30_000);
this.pingInterval.unref();
}
/** Shut down the WebSocket server and stop keepalive. */
destroy(): void {
if (this.pingInterval) {
clearInterval(this.pingInterval);
this.pingInterval = null;
}
if (this.wss) {
this.wss.close();
this.wss = null;
}
}
}