Websocket API

Documentation for websocket API

Notification

The structure of notification is following in all channels:

{
    "channel": "channel_name",
    "body": "<object or array>"  // depends on channel
}

Subscribe

To receive updates from websocket API send subscribe request to server.

{
    "method": "subscribe",
    "body": {
        "channel": "<CHANNEL_NAME>",
        "filters": {
            // pass channel filters
        }
    }
}

Now 3 channels are supported:

• head - receive information about indexer state. Channel does not have any filters. Subscribe message should looks like:

{
    "method": "subscribe",
    "body": {
        "channel": "head"
    }
}

Notification body of responses.State type will be sent to the channel.

• blocks - receive information about new blocks. Channel does not have any filters. Subscribe message should looks like:

{
    "method": "subscribe",
    "body": {
        "channel": "blocks"
    }
}

Notification body of responses.Block type will be sent to the channel.

• gas_price - receive information about current gas price. Channel does not have any filters. Subscribe message should looks like:

{
    "method": "subscribe",
    "body": {
        "channel": "gas_price"
    }
}

Notification body of responses.GasPrice type will be sent to the channel.

Unsubscribe

To unsubscribe send unsubscribe message containing one of channel name describing above.

{
    "method": "unsubscribe",
    "body": {
        "channel": "<CHANNEL_NAME>",
    }
}

Code example

const WebSocket = require('ws');

const websocketUrl = 'wss://api-mainnet.celenium.io/v1/ws';
const apiKey = '__YOUR__API__KEY__';

const ws = new WebSocket(websocketUrl, {
    headers: {
        'apiKey': `${apiKey}`,
    }
});

// Event: Connection established
ws.on('open', () => {
    console.log('Connected to the WebSocket server');

    ws.send(JSON.stringify({
        method: "subscribe",
        body: {
          channel: "blocks"
        }
      }));
});

// Event: Message received from the server
ws.on('message', (data) => {
    console.log('Message received:', data.toString());
});

// Event: Connection closed
ws.on('close', () => {
    console.log('Connection closed');
});

// Event: Error occurred
ws.on('error', (error) => {
    console.error('WebSocket error:', error);
});