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Compiling and deploying an Ethereum Smart Contract, using solc and web3.
const fs = require('fs');
const solc = require('solc');
const Web3 = require('web3');
// Connect to local Ethereum node
const web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"));
// Compile the source code
const input = fs.readFileSync('Token.sol');
const output = solc.compile(input.toString(), 1);
const bytecode = output.contracts['Token'].bytecode;
const abi = JSON.parse(output.contracts['Token'].interface);
// Contract object
const contract = web3.eth.contract(abi);
// Deploy contract instance
const contractInstance ={
data: '0x' + bytecode,
from: web3.eth.coinbase,
gas: 90000*2
}, (err, res) => {
if (err) {
// Log the tx, you can explore status with eth.getTransaction()
// If we have an address property, the contract was deployed
if (res.address) {
console.log('Contract address: ' + res.address);
// Let's test the deployed contract
// Quick test the contract
function testContract(address) {
// Reference to the deployed contract
const token =;
// Destination account for test
const dest_account = '0x002D61B362ead60A632c0e6B43fCff4A7a259285';
// Assert initial account balance, should be 100000
const balance1 =;
console.log(balance1 == 1000000);
// Call the transfer function
token.transfer(dest_account, 100, {from: web3.eth.coinbase}, (err, res) => {
// Log transaction, in case you want to explore
console.log('tx: ' + res);
// Assert destination account balance, should be 100
const balance2 =;
console.log(balance2 == 100);

thanks! this is very nice. I'm very new to this and I have a question. I am running a testrpc node on the 8545 port. I am just wondering now how I can actually run this javascript? I installed all the required node modules. Do I just put it in an html and open it with the browser? Thanks!

Hi @tomconte, does this still work for you since the Solidity 0.4.9 update? I keep getting "Cannot read property 'bytecode' of undefined". Cheers

linneacfritz commented Mar 9, 2017

@Shauneoo Hi, I had the same problem you did. And I discovered what I think may be the reason. The output becomes {"contracts":{":NameOfContract":{"assembly"... and so on, with an extra colon in front of NameOfContract. So when you call it in your code, you have to write "const bytecode = output.contracts[':Token'].bytecode;" instead of as before, without the colon. Same thing with "const abi = JSON.parse(output.contracts[':Token'].interface);" Then, the name parses correctly. HTH :)

base698 commented May 26, 2017

Who is the from in this case:

I deployed and it said I don't have enough gas. Using the greeter example contract. I also had to use geth to run rpc unlocked....

ar412 commented Jul 5, 2017

I have Token.sol that it is referring to.
When deployed with node it is giving error:

Error: Cannot find module 'web3'

And with npm
TypeError: Cannot read property 'bytecode' of undefined

ar412 commented Jul 5, 2017

@base698 Can you help me out?

For those wondering how to run this:

open a command prompt or terminal and type node....then all of the commands should work

The problem can be resolved by changing the name of Token. If you print the json string ,you will find the property of 'Token' should be ':Token'. So just change '[Token]' to '[:Token]'. Best wishes!

streamerd commented Jan 3, 2018

Hi all, I am currently having a TypeError;

$ node app.js

TypeError: web3.eth.contract is not a function
at Object. (/Users/foo/Developer/btc/contracts/app.js:15:27)
at Module._compile (module.js:409:26)
at Object.Module._extensions..js (module.js:416:10)
at Module.load (module.js:343:32)
at Function.Module._load (module.js:300:12)
at Function.Module.runMain (module.js:441:10)
at startup (node.js:139:18)
at node.js:974:3

node -v : v4.6.0
npm -v : 2.15.9
on OSX : 10.12.6 (Sierra)

streamerd commented Jan 3, 2018

I've changed the code a little bit, seems we need to use 'Contract'' instead of 'contract' while instance generation.

// app.js
// Deploy contract instance

const abi = JSON.parse(output.contracts[':Token'].interface);
const contract = new web3.eth.Contract(abi, '0xde0B295669a9FD93d5F28D9Ec85E40f4cb697BAe', {
    data: '0x' + bytecode,
    from: web3.eth.coinbase,
    gas: 90000*2
}, (err, res) => {
    if (err) {

now there is no error back.
I've referenced from for the address 0x..BAe

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