Using Binance WebSocket Inbound Data with Ethereum

As a developer, you probably want to integrate real-time market data into your applications. One popular solution is to use the Binance WebSockets API to fetch real-time inbound data. In this article, we will explore how to use Binance WebSocket inbound data to track Ethereum prices.

Prerequisites

Before diving in, make sure you have:

• A Binance account and a valid API key.

• The binance-js package installed as a dependency: npm install binance-js

• Basic knowledge of JavaScript and the WebSocket API.

Getting Started with the Binance WebSockets API

To use the Binance WebSockets API, you will need to:

• Create an API key on the Binance website.

• Obtain a WebSocket URL by following the instructions in the Binance documentation.

For Ethereum prices, we will use the eth-apis package, which provides an easy and convenient way to interact with the WebSockets API of the Ethereum blockchain.

Installation

To get started, install the required packages:

npm install binance-js eth-apis

Setting up a WebSocket connection

Here is an example of how to establish a connection to the Binance WebSocket endpoint:

const { Web3 } = require('web3');
const Binance = require('binance-js');
const apiKey = 'YOUR_API_KEY';
const apiSecret = 'YOUR_API_SECRET';
const WebSocketUrl = 'wss://apis.binance.com/1/websocket';
const web3 = new Web3(new Web3.providers.HttpProvider(WebSocketUrl));
const ethApi = new Binance({
apiKey,
apiSecret,
});
// Example: Retrieving Ethereum token prices
ethApi.get('ETHusdPrice', function(error, response) {
if (error) console.error(err); // Replace with a log message of your choice
else {
const price = response.price;
console.log(Current ETH price: ${price});
}
});

In this example, we instantiate the eth-apis package and pass in our API key. We then establish a connection to the Binance WebSocket endpoint using the Web3 provider.

Parsing incoming messages

Incoming data is sent as JSON messages over WebSockets. To parse these messages, you will need to use a library like json-stringify-safe. Here is an example:

const { parseMessage } = require('json-stringify-safe');
// Example: Parse the first message from Binance (in this case a price update)
ethApi.get('ETHusdPrice', function(error, response) {
if (error) console.error(err); // Replace with a log message of your choice
else {
const data = parseMessage(response);
const {symbol, timestamp, price} = data;
console.log(Received ETH price update at ${timestamp}: $${price});
}
});

In this example, we use the parseMessage function to safely parse the incoming message from Binance.

Integrating into your application

To integrate our WebSocket connection into your application, you will need to:

• Create a socket event listener for new messages from Binance.

• Process incoming messages and update your data accordingly.

Here is an example of how we can create a simple WebSocket server using the ws library:

“javascript

const WebSocket = require('ws');

// Create a socket connection to Binance's WebSocket endpoint

const wss = new WebSocket.Server({ port: 8080 });

wss.on('connection', (ws) => {

console.log('Client connected...');

// Handle incoming messages from Binance

ws.on('message', (message) => {

const data = parseMessage(message);

if (data && data.symbol === 'ETH') {

console.log(Received ETH price update: ${data.price});

} else {

console.log(Ignoring unknown symbol: ${data.symbol}`);

}

});

// Close the connection when the connection is disconnected

ws.on(‘close’, () => {

console.log(‘Client disconnected…