I am trying to deploy a contract on testrpc using web3.js,

  1. contract deploys fine when I deploy it from remix, it uses roughly the same amount of gas as the estimate.

  2. However, when I try to deploy the same contract using web3.js, I keep running into "out of gas" error, even though I am supplying 5x the gas estimate.

I am obviously making some mistake in my deployment script...but I have gone over the script and can't spot the problem....some help from a knowing hand would be much appreciated

let source = fs.readFileSync('./xyz.sol', 'utf8');
    let compiledContract = solc.compile(source, 1);
    let abi = compiledContract.contracts[':Xyz'].interface;
    let bytecode = compiledContract.contracts[':Xyz'].bytecode; 

    let bContract = new web3.eth.contract(JSON.parse(abi));

    let gasEstimate = web3.eth.estimateGas({data : bytecode});
    console.log(`GASESTIMATE : ${gasEstimate}`);  // <------------ returns value 120000

    let deployData = bContract.new.getData(name, choices, closesOn, min, {  data : bytecode, });

    let rawTx = {
        from: runENV.acctAddr,
        nonce: web3.toHex(web3.eth.getTransactionCount(runENV.acctAddr)),
        gasPrice: web3.toHex(web3.eth.gasPrice),
        gasLimit: web3.toHex(5*gasEstimate), // <------------- giving 5x gasestimate
        data: deployData,

    let tx = new Tx(rawTx);

    let serialzedTx = tx.serialize().toString('hex');

    web3.eth.sendRawTransaction( '0x' + serialzedTx, (err, res) => {
            if(err) { console.log(`Error  - ${err}`); } 
            else { console.log(`Xyz contract deployed successfully ${res}`);     }
  • 1
    You didn't say what you're using for a chain, e.g. ganache-cli, private chain using geth version x, or the version of solidity you use to compile the contract. There is a compatibility matrix issue because protocol changes (Byzantium) mean you can't just use any-to-any. Also, the contract constructor could be a factor. Sep 6 '18 at 19:59
  • I mentioned it in the first line, sorry it was obscured by later stuff, I am trying to deploy it locally on ganache...I get the same error when deploying it on rinkeby. BTW I can deploy to both of these successfully if I do the deployment directly from remix....which is why i think the problem is in my code
    – satyendra
    Sep 6 '18 at 20:26
  • Finally figured this out after three days of trying everything....wish we had a little better documentation. Looks like this was caused by some compatibility issues between compiler and the blockchain...instead of using solc/solcjs to compile the code, I took the bytecode from remix and pasted that into my code...and boom everything works. Thanks to Rob Hitchins from B9lab for poitning out that there might be a compatibility issue.
    – satyendra
    Sep 7 '18 at 17:37

A common problem I used to have is that the bytecode needs to be prefixed by '0x'.

I've used this code to deploy a simple contract to a local ganache instance using web3 v1.0

const Web3 = require('web3');
const solc = require('solc');

const web3 = new Web3("http://localhost:8545");

const recipientSource = `
pragma solidity ^0.4.20;
contract Recipient {
  uint public id;
  function deposit(uint _id) public payable {
    id = _id;

function compileContract(source, name) {
  const result = solc.compile(source, 1);
  const compiled = result.contracts[`:${name}`];
  return compiled;

async function deployQueryContract() {
  const compiled = compileContract(recipientSource, 'Recipient');

  const accounts = await web3.eth.personal.getAccounts();

  const Recipient = new web3.eth.Contract(JSON.parse(compiled.interface));

  const toDeploy =  Recipient.deploy({
    data: `0x${compiled.bytecode}`

  const gas = await toDeploy.estimateGas();

  console.log(`Gas: ${gas}`);

  const recipient = await toDeploy.send({
    from: accounts[0],
    gas: `0x${gas.toString(16)}`,
    gasPrice: '30000000000'

  console.log(`Deployed at: ${recipient.options.address}`);
  console.log(`ABI: ${compiled.interface}`);

  await recipient.methods.deposit(4321)
    from: accounts[0],
    value: 1000

  const result = await recipient.methods.id().call();
  console.log(`Result: ${result}`);


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