WebSocket API

The WebSocket API provides real-time bidirectional communication for receiving real-time data streams from USV.

Connection

Endpoint

ws://localhost:8081

Authentication

Authenticate using JWT Token:

const token = 'your-jwt-token';
const ws = new WebSocket(`ws://localhost:8081?token=${token}`);

Message Format

Subscribe to Data Stream

Send:

{
  "action": "subscribe",
  "device_id": "USV-2024-001",
  "streams": ["telemetry", "sensors"]
}

Response:

{
  "type": "subscription_ack",
  "streams": ["telemetry", "sensors"]
}

Telemetry Data

{
  "type": "telemetry",
  "device_id": "USV-2024-001",
  "timestamp": "2024-01-15T10:30:00Z",
  "data": {
    "latitude": 31.2304,
    "longitude": 121.4737,
    "speed": 5.2,
    "heading": 90,
    "battery": 78
  }
}

Sensor Data

{
  "type": "sensor",
  "device_id": "USV-2024-001",
  "sensor_type": "water_quality",
  "timestamp": "2024-01-15T10:30:00Z",
  "data": {
    "ph": 7.2,
    "dissolved_oxygen": 8.5,
    "temperature": 25.3
  }
}

JavaScript Example

const ws = new WebSocket('ws://localhost:8081?token=your-token');

ws.onopen = () => {
  console.log('Connected to WebSocket');

  // Subscribe to data stream
  ws.send(JSON.stringify({
    action: 'subscribe',
    device_id: 'USV-2024-001',
    streams: ['telemetry', 'sensors']
  }));
};

ws.onmessage = (event) => {
  const message = JSON.parse(event.data);

  switch(message.type) {
    case 'telemetry':
      updateMap(message.data);
      break;
    case 'sensor':
      updateSensorDisplay(message.data);
      break;
  }
};

ws.onerror = (error) => {
  console.error('WebSocket error:', error);
};

ws.onclose = () => {
  console.log('WebSocket closed');
};

Python Example

import asyncio
import websockets
import json

async def stream_data():
    uri = "ws://localhost:8081?token=your-token"

    async with websockets.connect(uri) as websocket:
        # Subscribe to data stream
        await websocket.send(json.dumps({
            "action": "subscribe",
            "device_id": "USV-2024-001",
            "streams": ["telemetry", "sensors"]
        }))

        # Receive data
        async for message in websocket:
            data = json.loads(message)
            print(f"Received: {data}")

asyncio.run(stream_data())

See more at API Overview.