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@tomconte
Created December 13, 2016 09:32
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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 = contract.new({
data: '0x' + bytecode,
from: web3.eth.coinbase,
gas: 90000*2
}, (err, res) => {
if (err) {
console.log(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);
// Let's test the deployed contract
testContract(res.address);
}
});
// Quick test the contract
function testContract(address) {
// Reference to the deployed contract
const token = contract.at(address);
// Destination account for test
const dest_account = '0x002D61B362ead60A632c0e6B43fCff4A7a259285';
// Assert initial account balance, should be 100000
const balance1 = token.balances.call(web3.eth.coinbase);
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 = token.balances.call(dest_account);
console.log(balance2 == 100);
});
}
@streamerd
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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
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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) {
        console.log(err);
        return;
    }

now there is no error back.
I've referenced from https://web3js.readthedocs.io/en/1.0/web3-eth-contract.html for the address 0x..BAe

@VanThanh1812
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VanThanh1812 commented Apr 12, 2018

Anyone can help me, when I use solc and build in webpack, I get error: Uncaught TypeError: Cannot read property 'prototype' of undefined
at patch (graceful-fs.js:166) and load web fail? Thank you

@ADitya024
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ADitya024 commented Apr 19, 2018

Hello guys,
I am facing a error : TypeError: Cannot read property 'bytecode' of undefined
occuring on line : const bytecode = output.contracts['Token'].bytecode;

@izotx
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izotx commented Jun 19, 2018

@ADitya024
Change it to:
output.contracts['Token']["bytecode"];

@shchye95
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Hi guys,

I am currently trying to adopt this source code for my school project. But may I know what is the folder structure for this project? Because I can't seemed to grasp how the code retrieve the Token.sol (Line 9)

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