oscope/tools/firehose.mjs at main · oscope/oscope

oscope/tools/firehose.mjs

OScope OScope: open source memecoin terminal for Solana f8ff931·

Oct 20, 2026

Code

39 lines (35 loc) · 1.95 KB

	// The firehose on its own: one connection to the stream, passed on to as many local readers as you like.
	// OScope itself already does this at ws://localhost:3000/firehose; use this when you want the stream without the page.
	//
	// npm run firehose -> ws://127.0.0.1:3100
	// readers may add ?pools=pump,pump-amm to get only those pools
	//
	// Settings: FEED_URL (the stream), FIREHOSE_PORT (3100), FIREHOSE_HOST (127.0.0.1).
	// Point OScope at it with FEED_URL=ws://127.0.0.1:3100 to run several things on one stream connection.
	import { WebSocketServer } from 'ws';
	import { config } from '../src/config.mjs';
	import { connectFeed } from '../src/feed.mjs';

	const port = Number(process.env.FIREHOSE_PORT) \|\| 3100;
	const host = process.env.FIREHOSE_HOST \|\| '127.0.0.1';
	const readers = new Set();
	let n = 0;

	const wss = new WebSocketServer({ port, host, maxPayload: 4096, perMessageDeflate: false });
	wss.on('connection', (ws, req) => {
	if (req.headers.origin) return ws.close(1008, 'tools only'); // web pages you visit cannot read it
	const pools = new URL(req.url, 'http://x').searchParams.get('pools');
	const r = { ws, pools: pools ? new Set(pools.split(',')) : null };
	readers.add(r);
	ws.on('close', () => readers.delete(r));
	});
	wss.on('listening', () => console.log(`\n Firehose on ws://${host}:${port}\n Stream ${config.feedUrl}\n`));
	wss.on('error', e => { console.error(e.code === 'EADDRINUSE' ? `Port ${port} is in use: FIREHOSE_PORT=${port + 1} npm run firehose` : e.message); process.exit(1); });

	connectFeed(config.feedUrl, (f, raw) => {
	n++;
	let text = raw;
	for (const r of readers) {
	if (r.pools && !r.pools.has(f.pool)) continue;
	if (r.ws.bufferedAmount > 8e6) { r.ws.terminate(); continue; }
	r.ws.send(text ??= JSON.stringify(f));
	}
	});

	setInterval(() => { console.log(`${new Date().toTimeString().slice(0, 8)} ${n.toLocaleString('en-US')} messages in the last 30 s, ${readers.size} reader(s)`); n = 0; }, 30000).unref();