KuCoin JavaScript SDK example: ws-spot-public.ts
KuCoin websocket spot public JavaScript example for the Siebly KuCoin SDK, covering exchange REST API and WebSocket integration, setup, and production SDK docs.
We use environment variables in our examples for API keys. It is your responsibility to manage and secure your keys appropriately.
examples/Kucoin/WebSockets/ws-spot-public.ts
What this example covers
- KuCoin WebSocket stream JavaScript example.
- Uses the Siebly KuCoin SDK package
kucoin-apiinstead of hand-written WebSocket plumbing. - Source path:
Kucoin/WebSockets/ws-spot-public.ts. - Imports SDK symbols including
WebsocketClient. - Calls SDK methods such as
on(),connect(),subscribe().
How to use this example
- Start here for the specific request or stream pattern, then check the matching SDK guide for install, credentials, and operational notes.
- For WebSocket examples, keep reconnect, resubscribe, heartbeat, and event-handler behavior explicit in your service.
- Open the repository source when you need the latest committed version: GitHub source file.
/* eslint-disable @typescript-eslint/no-unused-vars */import { WebsocketClient, WsTopicRequest } from 'kucoin-api'; async function start() { // Optional: fully customise the logging experience by injecting a custom logger // const logger: typeof DefaultLogger = { // ...DefaultLogger, // trace: (...params) => { // if ( // [ // 'Sending ping', // 'Sending upstream ws message: ', // 'Received pong', // ].includes(params[0]) // ) { // return; // } // console.log('trace', params); // }, // }; // const client = new WebsocketClient({}, logger); const client = new WebsocketClient(); client.on('open', (data) => { console.log('open: ', data?.wsKey); }); // Data received client.on('update', (data) => { console.info('data received: ', JSON.stringify(data)); }); // Something happened, attempting to reconnect client.on('reconnect', (data) => { console.log('reconnect: ', data); }); // Reconnect successful client.on('reconnected', (data) => { console.log('reconnected: ', data); }); // Connection closed. If unexpected, expect reconnect -> reconnected. client.on('close', (data) => { console.error('close: ', data); }); // Reply to a request, e.g. "subscribe"/"unsubscribe"/"authenticate" client.on('response', (data) => { console.info('response: ', data); // throw new Error('res?'); }); client.on('exception', (data) => { console.error('exception: ', { msg: data.msg, errno: data.errno, code: data.code, syscall: data.syscall, hostname: data.hostname, }); }); try { // Optional: await a connection to be ready before subscribing (this is not necessary) // await client.connect('spotPublicV1'); /** * Use the client subscribe(topic, market) pattern to subscribe to any websocket topic. * * You can subscribe to topics one at a time or many in one request. Topics can be sent as simple strings: * */ client.subscribe('/market/ticker:BTC-USDT,ETH-USDT', 'spotPublicV1'); client.subscribe('/market/snapshot:KCS-BTC', 'spotPublicV1'); /** * Or, as an array of simple strings * */ client.subscribe( ['/market/ticker:BTC-USDT,ETH-USDT', '/market/snapshot:KCS-BTC'], 'spotPublicV1', ); /** * Or send a more structured object with parameters * */ const subRequest: WsTopicRequest = { topic: '/market/ticker:BTC-USDT', /** Anything in the payload will be merged into the subscribe "request", allowing you to send misc parameters supported by the exchange. * For more info on parameters, see: https://www.kucoin.com/docs/websocket/basic-info/subscribe/introduction */ payload: { id: 123456, response: false, }, }; client.subscribe(subRequest, 'spotPublicV1'); /** * Or, send an array of structured objects with parameters, if you wanted to send multiple in one request * */ // client.subscribe([subRequest1, subRequest2, etc], 'spotPublicV1'); /** * Other spot websocket topics: */ client.subscribe( [ '/market/ticker:BTC-USDT,ETH-USDT', '/market/ticker:all', '/market/snapshot:KCS-BTC', '/market/snapshot:BTC', '/spotMarket/level1:BTC-USDT,ETH-USDT', '/market/level2:BTC-USDT,ETH-USDT', '/spotMarket/level2Depth5:BTC-USDT,ETH-USDT', '/spotMarket/level2Depth50:BTC-USDT,ETH-USDT', '/market/candles:BTC-USDT_1hour', '/market/match:BTC-USDT,ETH-USDT', ], 'spotPublicV1', ); /** * Other margin websocket topics, which also use the "spotPublicV1" WsKey: */ client.subscribe( [ '/indicator/index:USDT-BTC,ETH-USDT', '/indicator/markPrice:USDT-BTC,ETH-USDT', ], 'spotPublicV1', ); } catch (e) { console.error('Subscribe exception: ', e); }} start();