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Streaming Quickstart

This recipe walks through:

Creating a stream-scoped API key
Connecting to /v1/stream
Subscribing to Hyperliquid allMids + Polymarket book on one connection
Handling pings and reconnecting cleanly

You'll need websocat or any WS client.

Mint a stream-scoped key

bashTOKEN=$(curl -sS -X POST https://api.artery.questflow.ai/keys \
  -H "Content-Type: application/json" \
  -d '{"name":"stream-recipe","userId":"u-1","scopes":["stream"]}' \
  | jq -r .plaintext)

The token must include the stream scope or the WS upgrade returns 403 forbidden_scope.

Connect
```
bashwebsocat "wss://api.artery.questflow.ai/v1/stream?token=$TOKEN"
```
Artery accepts the token via either the token query param or the Authorization: Bearer <token> header. Query is convenient for browser WebSocket which can't set headers.
On a successful upgrade you'll see no immediate frame — the server waits for your first subscribe.
Subscribe to multiple providers
Channels are flat strings of the form artery:stream:{provider}:{marketKey}. Use * to match every market under a provider/feed.
```
json{
  "type": "subscribe",
  "channels": [
    "artery:stream:hyperliquid_perp:*",
    "artery:stream:polymarket:0xCONDITION_ID"
  ]
}
```
Server reply:
```
json{ "type": "subscribed", "subscription_id": "sub_01HMPK..." }
```
From this point you'll receive event frames whenever the upstream provider emits a matching update.

Parse events

Every event carries type = "<provider>.<native_event_type>":

json{
  "type": "event",
  "subscription_id": "sub_01HMPK...",
  "data": {
    "type": "hyperliquid.allMids",
    "provider": "hyperliquid",
    "marketId": "*",
    "payload": {
      "BTC": "67542.0",
      "ETH": "3201.7",
      "100000421": "0.625"
    },
    "receivedAt": 1714928400123
  }
}

The payload is the upstream feed's raw shape. For HL allMids, keys are coin tickers + numeric asset ids (HIP-3 + HIP-4). For Polymarket book it's { bids, asks, hash, market }.

Handle the heartbeat
Every 30 seconds the server pushes a JSON keepalive:
```
json{ "type": "pong" }
```
You can ignore it — the server only closes the connection (code 1001) if there's been no inbound frame from your client for >60s. Sending any subscribe / unsubscribe / {"type":"ping"} resets that timer.

Reconnect with backoff

On any close, reconnect with exponential backoff capped at 30s. Re-issue your subscriptions on the new connection — there is no server-side resumption (deliberately, to keep the gateway stateless).

tslet delay = 500;
while (true) {
  try {
    await connectAndSubscribe();
    delay = 500;
  } catch (e) {
    await sleep(delay);
    delay = Math.min(delay * 2, 30_000);
  }
}

Full Node.js example

jsimport WebSocket from 'ws';
 
const TOKEN = process.env.ART_TOKEN;
const ws = new WebSocket(`wss://api.artery.questflow.ai/v1/stream?token=${TOKEN}`);
 
ws.on('open', () => {
  ws.send(
    JSON.stringify({
      type: 'subscribe',
      channels: ['artery:stream:hyperliquid_perp:*'],
    }),
  );
});
 
ws.on('message', (raw) => {
  const msg = JSON.parse(raw.toString());
  // Server pushes {type:"pong"} every 30s as a keepalive — ignore.
  if (msg.type === 'pong') return;
  if (msg.type === 'event') {
    const mids = msg.data?.payload?.data ?? msg.data?.payload;
    console.log('mid update:', Object.keys(mids ?? {}).length, 'assets');
  }
});
 
ws.on('close', () => {
  console.log('closed — reconnect with backoff');
});

Subscription patterns

You want	Channel string
All HL mids one update at a time	`artery:stream:hyperliquid_perp:*`
Single HL coin orderbook	`artery:stream:hyperliquid_perp:BTC`
HIP-4 outcome market	`artery:stream:hyperliquid_perp:100000421`
Polymarket book by token id	`artery:stream:polymarket:<token_id>`
Kalshi market deltas (planned — needs RSA)	`artery:stream:kalshi:<ticker>`

Warning

Kalshi streaming is RSA-gated. Even public Kalshi channels return HTTP 401 on connect unless the handshake carries RSA-PSS signed headers. Artery will surface this as subscription_error with code: rsa_required until M3-4 ships.

Streaming Quickstart#

Full Node.js example#

Subscription patterns#

See also#

Streaming Quickstart

Full Node.js example

Subscription patterns

See also