1const { ApiPromise, WsProvider } = require('@polkadot/api');23const connect = async () => {4 const wsEndpoint = 'ws://127.0.0.1:9944'5 const api = new ApiPromise({provider: new WsProvider(wsEndpoint)});6 await api.isReadyOrError;78 const head = (await api.rpc.chain.getHeader()).number.toNumber();9 if(head < 1) throw Error('No block #1');1011 await api.disconnect();12}1314const sleep = time => {15 return new Promise(resolve => {16 setTimeout(() => resolve(), time);17 });18}1920const main = async () => {21 while(true) {22 try {23 await connect();24 break;25 }26 catch(e) {27 await sleep(10000);28 }29 }30}3132main().then(() => process.exit(0)).catch(e => {33 console.error(e);34 process.exit(1);35});