Error "The contract code couldn't be stored, please check your gas amount"

Question

UPDATE: I manage to figure out what's wrong is in this line

var byteCode = compiledCode.contracts[':TestStorage'].***byteCode***;

and it should be

var byteCode = compiledCode.contracts[':TestStorage'].***bytecode***;

Completely typo, but it makes me realize that this error is quite general so that could be a lot of reasons.

I have see a lot of people raised this question, but none of the answer/solution could solve my problem so ask here.

I setup truffle on my Windows OS and use Ganache as my personal development blockchain. I create a Node project, use Express setup a server handling request and deploy my contract. I have this error returned:

The contract code couldn't be stored, please check your gas amount

My code is below:

var router = express.Router();
var logger = require('./logger');
var pool = require('./pool');
var web3 = require('./getWeb3');
const fs = require('fs');
const solc = require('solc');

router.get('/',  function(req, res, next){
    var code = fs.readFileSync('TestStorage.sol').toString();
    var compiledCode = solc.compile(code);
    var abi = JSON.parse(compiledCode.contracts[':TestStorage'].interface);
    var TSContract = web3.eth.contract(abi);
    var byteCode = compiledCode.contracts[':TestStorage'].byteCode;

    console.log("Unlocking coinbase account");
    var password = "";
    try {
        web3.personal.unlockAccount(web3.eth.coinbase, password);
    } catch(e) {
        console.log(e);
        return;
    }

    var deployedContract = TSContract.new({data: '0x' + byteCode, from: web3.eth.coinbase, gas: 6721975}, (err, res) => {
        if (err) {
            console.log('error message: ' + err);
            return;
        }

        // Log the tx, you can explore status with eth.getTransaction()
        console.log(res.transactionHash);

        // If we have an address property, the contract was deployed
        if (res.address) {
            console.log('Contract address: ' + res.address);
        }
    });
}

getWeb3.js

const Web3 = require('web3');

var web3 = new Web3(new Web3.providers.HttpProvider('http://127.0.0.1:9545'));

module.exports=web3;

I have tried below 1. adjust gas in new() and if it greater than 6721975, then error - "Error: Exceeds block gas limit" returned. 2. I manually input above steps in node command line and contact can be deployed successfully.