Posting order code

test.js

const connect = require('@0x/connect');
const subproviders = require('@0x/subproviders');
const utils = require('@0x/utils');
const wrapper = require('@0x/web3-wrapper');
const orderUtils = require('@0x/order-utils');
const contractAddresses = require('@0x/contract-addresses');
const handler = {
    onUpdate: (...args) => console.log('onUpdate:', ...args),
    onError: (...args) => console.log('onError:', ...args),
    onClose: (...args) => console.log('onClose:', ...args),
}
// const WS_URL = 'wss://kovan.api.0x.org/sra/v3';
// const HTTP_URL = 'https://kovan.api.0x.org/sra/v3';
const CHAIN_ID = 1337;
const WS_URL = 'ws://localhost:3000/';
const HTTP_URL = 'http://localhost:3000/sra/v3';
const PRIVATE_KEY = 'f2f48ee19680706196e2e339e5da3491186e0c4c5030670656b0e0164837257d'; // ganache
const PUBLIC_KEY = '0x5409ED021D9299bf6814279A6A1411A7e866A631'; // ganache
const addresses = contractAddresses.getContractAddressesForChainOrThrow(CHAIN_ID);
const ONE_SECOND_MS = 1000;
const ONE_MINUTE_MS = ONE_SECOND_MS * 60;
const TEN_MINUTES_MS = ONE_MINUTE_MS * 10;
const DECIMALS = 18;
const NULL_ADDRESS = '0x0000000000000000000000000000000000000000';
const NULL_BYTES = '0x';
const ZERO = new utils.BigNumber(0);
const GANACHE_NETWORK_ID = 50;
const KOVAN_NETWORK_ID = 42;
const ROPSTEN_NETWORK_ID = 3;
const RINKEBY_NETWORK_ID = 4;
const createPrivateKeyProvider = () => {
    const pe = new subproviders.Web3ProviderEngine();
    const pkw = new subproviders.PrivateKeyWalletSubprovider(PRIVATE_KEY);
    pe.addProvider(pkw);
    utils.providerUtils.startProviderEngine(pe);
    return pe;
};
const provider = createPrivateKeyProvider();
const getRandomFutureDateInSeconds = () => {
    return new utils.BigNumber(Date.now() + TEN_MINUTES_MS).div(ONE_SECOND_MS).integerValue(utils.BigNumber.ROUND_CEIL);
};
const createSignedOrderAsync = async () => {
    const makerAddress = PUBLIC_KEY;
    const order = {
        chainId: CHAIN_ID,
        exchangeAddress: addresses.exchange,
        makerAddress,
        takerAddress: NULL_ADDRESS,
        senderAddress: NULL_ADDRESS,
        feeRecipientAddress: NULL_ADDRESS,
        expirationTimeSeconds: getRandomFutureDateInSeconds(),
        salt: orderUtils.generatePseudoRandomSalt(),
        makerAssetAmount: new utils.BigNumber(7),
        takerAssetAmount: new utils.BigNumber(7),
        makerAssetData: orderUtils.assetDataUtils.encodeERC20AssetData(addresses.zrxToken), 
        takerAssetData: orderUtils.assetDataUtils.encodeERC20AssetData(addresses.etherToken),
        makerFeeAssetData: NULL_BYTES,
        takerFeeAssetData: NULL_BYTES,
        makerFee: ZERO,
        takerFee: ZERO,
    };
    const signedOrder = await orderUtils.signatureUtils.ecSignOrderAsync(provider, order, makerAddress);
    return signedOrder
};
const connectWebsocket = async () => {
    try {
        const channel = await connect.ordersChannelFactory.createWebSocketOrdersChannelAsync(WS_URL, handler);
        channel.subscribe({});
        console.log('Successfully connected');
    } catch (e) {
        console.log(e);
    }
}
const postOrderAsync = async () => {
    try {
        const client = new connect.HttpClient(HTTP_URL);
        const signedOrder = await createSignedOrderAsync();
        console.log(signedOrder);
        await client.submitOrderAsync(signedOrder);
    } catch (err) {
        console.log(err);
    }
};
// createSignedOrderAsync().then(a => console.log(JSON.stringify(a)))
postOrderAsync();