Bitquery_Javascript

const WebSocket = require('ws');

const API_KEY = '**********************';
const WS_URL = 'wss://streaming.bitquery.io/graphql';

const client = new WebSocket(WS_URL, ['graphql-ws'], {
    headers: {
        Authorization: `Bearer ${API_KEY}`
    }
});

client.on('open', () => {
    console.log('Opened connection');

    // Initialization message
    const initMessage = JSON.stringify({ type: 'connection_init' });
    client.send(initMessage);

    // Simulate delay as in Java code
    setTimeout(() => {
        const payload = {
            id: '1',
            type: 'start',
            payload: {
                query: `
          subscription MyQueryWithVariables($network: evm_network!, $limit: Int!) {
            EVM(network: $network) {
              Transfers(limit: { count: $limit }, orderBy: { descending: Block_Number }) {
                Block {
                  Number
                  Hash
                }
                Transfer {
                  Currency {
                    Symbol
                    Name
                  }
                  Amount
                }
              }
            }
          }
        `,
                variables: {
                    network: 'eth',
                    limit: 2
                }
            }
        };
        client.send(JSON.stringify(payload));
    }, 1000);
});

client.on('message', (message) => {
    const jsonObject = JSON.parse(message);
    if (jsonObject.type !== 'ka') {
        console.log(`Received: ${message}`);
    }
});

client.on('close', (code, reason) => {
    console.log(`Closed: ${reason}`);
});

client.on('error', (error) => {
    console.error('WebSocket Error:', error);
});