Subscribe to Device Events

There are two real options here, and they're not equivalent - pick based on whether you have a dashboard session available.

Option A - poll telemetry with just an API key

This is the only live-updates path that works with only an API key today; there is no API-key-authenticated push channel (see the callout below). It's still perfectly workable for most integrations:

curl "https://api.nexalware.com/api/v1/devices/dev_a1b2c3/telemetry/latest" \
  -H "X-Api-Key: $NEXALWARE_API_KEY"

{
  "relayState": true,
  "telemetry": [
    { "metric": "temperature", "value": 21.4, "timestamp": 1732000000 }
  ]
}

Poll this on whatever interval makes sense for your use case - seconds for something latency-sensitive, minutes for a dashboard widget. For a full history rather than just the latest value per metric, use GET /api/v1/devices/{deviceId}/telemetry instead.

Option B - the WebSocket feed, with a session token

GET /api/v1/ws pushes updates as they happen instead of making you poll, but it authenticates with a session token, not an API key:

const ws = new WebSocket(
  `wss://api.nexalware.com/api/v1/ws?token=${sessionAccessToken}`,
);

ws.onmessage = (event) => {
  const msg = JSON.parse(event.data);
  if (msg.type === 'initial_state') {
    // msg.devices: [{ deviceId, name, relay, isOnline, lastSeen }, ...]
  }
  // every message after that is a live event - see the reference below.
};

See the WebSocket reference for the full message catalog and connection details.