Send ERC20 token with web3

Question

I'm currently using 0.2x.x version of Web3 Javascript API. I deployed my custom ERC20 token by creating smart contract in solidity (on REMIX IDE). I installed the MetaMask and had a test on https://wallet.ethereum.org/ to send some custom ERC token to another my account. It worked well. I want to add the 'send custom ERC20 Token' function in my javascript code using Web3.

Here is my code below.

var http = require('http');
var Web3 = require('web3');
var Tx = require('ethereumjs-tx');

var abi = [{"...."}];
var data = '0x00..';
var contract_addr = '0x00..';
var owner = '0x00..';

var web3 = new Web3(new Web3.providers.HttpProvider("https://ropsten.infura.io/"));
web3.eth.getBlock("latest", (error, result) => {
//console.log('error:', error);
//console.log('results', result);
});

var myContract = web3.eth.contract(abi);
var myContractInstance = myContract.at(address);

eb3.eth.getDefaultAccount = owner;
var defaultAccount = web3.eth.getDefaultAccount;
console.log('DefaultAccount => ', defaultAccount);

var total = myContractInstance.totalSupply();
var balance = myContractInstance.balanceOf(defaultAccount);

console.log('DefulatAccount total => ',total);
console.log('DefaultAccount balance => ',balance);

var to = '0x00..';
var isAddress = web3.isAddress(to);

console.log('isAddress(to) => ',isAddress);
console.log('balanceOf(to) => ',myContractInstance.balanceOf(to));

I'm working on the 'Ropsten Testnet' and I sent some 'ether' for test using sendRawTransaction(). But what I want to do is just sending my custom ERC20 token. not the ether. How can I send my own token in this script? I have no idea. I tried to use sendTransaction() like below.

var rawTx = {
    from : defaultAccount,
    nonce : nonceHex,
    gasPrice : gasPriceHex,
    gas : gasHex,
    to : to,
    value : 100,
    data : data
};

web3.eth.sendTransaction(rawTx, function(err, transactionHash) {
    if (!err)
        console.log('transactionHash => ',transactionHash);
    else
        console.log(err);
});

I continuously received the error.

Error: Invalid JSON RPC response: ""
at Object.InvalidResponse (/Users/rachel/dev/test/node_modules/web3/lib/web3/errors.js:38:16)
at XMLHttpRequest.request.onreadystatechange (/Users/rachel/dev/test/node_modules/web3/lib/web3/httpprovider.js:119:24)
at XMLHttpRequestEventTarget.dispatchEvent (/Users/rachel/dev/test/node_modules/xhr2/lib/xhr2.js:64:18)
at XMLHttpRequest._setReadyState (/Users/rachel/dev/test/node_modules/xhr2/lib/xhr2.js:354:12)
at XMLHttpRequest._onHttpResponseEnd (/Users/rachel/dev/test/node_modules/xhr2/lib/xhr2.js:509:12)
at IncomingMessage.<anonymous> (/Users/rachel/dev/test/node_modules/xhr2/lib/xhr2.js:469:24)
at emitNone (events.js:111:20)
at IncomingMessage.emit (events.js:208:7)
at endReadableNT (_stream_readable.js:1056:12)
at _combinedTickCallback (internal/process/next_tick.js:138:11)

I really can't understand what is wrong with it. Please let me know some way to deal with this. Thanks!

Answer 1

All you need to do to resolve your issue is install web3 and ethereumjs-tx with npm install web3 ethereumjs-tx

You may refer the code below: 

var Tx = require('ethereumjs-tx');

var Web3 = require('web3')

var web3 = new Web3(new Web3.providers.HttpProvider('http://127.0.0.1:8545/'))

// set token source, destination and amount

var myAddress = "0xaa597b7e8aaffe9f2a187bedb472ef3455957560"

var toAddress = "0xa013927bffe9e879134061b9330a01884a65497c"

var amount = web3.utils.toHex(1e16)

// get transaction count, later will used as nonce

web3.eth.getTransactionCount(myAddress).then(function(v){console.log(v); count = v})  

// set your private key here, we'll sign the transaction below

var privateKey = new Buffer('6d...', 'hex')  

// Get abi array here https://etherscan.io/address/0x86fa049857e0209aa7d9e616f7eb3b3b78ecfdb0#code

var abiArray = [{"constant":true,"inputs":[],"name":"name","outputs":[{"name":"","type":"bytes32"}],"payable":false,"type":"function"},{"constant":false,"inputs":[],"name":"stop","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"guy","type":"address"},{"name":"wad","type":"uint256"}],"name":"approve","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"owner_","type":"address"}],"name":"setOwner","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"totalSupply","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"src","type":"address"},{"name":"dst","type":"address"},{"name":"wad","type":"uint256"}],"name":"transferFrom","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"decimals","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"dst","type":"address"},{"name":"wad","type":"uint128"}],"name":"push","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"name_","type":"bytes32"}],"name":"setName","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"wad","type":"uint128"}],"name":"mint","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"src","type":"address"}],"name":"balanceOf","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"stopped","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"authority_","type":"address"}],"name":"setAuthority","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"src","type":"address"},{"name":"wad","type":"uint128"}],"name":"pull","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"owner","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"wad","type":"uint128"}],"name":"burn","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"symbol","outputs":[{"name":"","type":"bytes32"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"dst","type":"address"},{"name":"wad","type":"uint256"}],"name":"transfer","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[],"name":"start","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"authority","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"src","type":"address"},{"name":"guy","type":"address"}],"name":"allowance","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"inputs":[{"name":"symbol_","type":"bytes32"}],"payable":false,"type":"constructor"},{"anonymous":true,"inputs":[{"indexed":true,"name":"sig","type":"bytes4"},{"indexed":true,"name":"guy","type":"address"},{"indexed":true,"name":"foo","type":"bytes32"},{"indexed":true,"name":"bar","type":"bytes32"},{"indexed":false,"name":"wad","type":"uint256"},{"indexed":false,"name":"fax","type":"bytes"}],"name":"LogNote","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"authority","type":"address"}],"name":"LogSetAuthority","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"owner","type":"address"}],"name":"LogSetOwner","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"from","type":"address"},{"indexed":true,"name":"to","type":"address"},{"indexed":false,"name":"value","type":"uint256"}],"name":"Transfer","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"owner","type":"address"},{"indexed":true,"name":"spender","type":"address"},{"indexed":false,"name":"value","type":"uint256"}],"name":"Approval","type":"event"}]

// Here you may get the abicode from a string or a file, here is a string case

// var abiArray = JSON.parse('[{"constant":true,"inputs":[],"name":"name","outputs":[{"name":"","type":"bytes32"}],"payable":false,"type":"function"},{"constant":false,"inputs":[],"name":"stop","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"guy","type":"address"},{"name":"wad","type":"uint256"}],"name":"approve","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"owner_","type":"address"}],"name":"setOwner","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"totalSupply","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"src","type":"address"},{"name":"dst","type":"address"},{"name":"wad","type":"uint256"}],"name":"transferFrom","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"decimals","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"dst","type":"address"},{"name":"wad","type":"uint128"}],"name":"push","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"name_","type":"bytes32"}],"name":"setName","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"wad","type":"uint128"}],"name":"mint","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"src","type":"address"}],"name":"balanceOf","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"stopped","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"authority_","type":"address"}],"name":"setAuthority","outputs":[],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"src","type":"address"},{"name":"wad","type":"uint128"}],"name":"pull","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"owner","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"wad","type":"uint128"}],"name":"burn","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"symbol","outputs":[{"name":"","type":"bytes32"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"dst","type":"address"},{"name":"wad","type":"uint256"}],"name":"transfer","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[],"name":"start","outputs":[],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"authority","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"src","type":"address"},{"name":"guy","type":"address"}],"name":"allowance","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"inputs":[{"name":"symbol_","type":"bytes32"}],"payable":false,"type":"constructor"},{"anonymous":true,"inputs":[{"indexed":true,"name":"sig","type":"bytes4"},{"indexed":true,"name":"guy","type":"address"},{"indexed":true,"name":"foo","type":"bytes32"},{"indexed":true,"name":"bar","type":"bytes32"},{"indexed":false,"name":"wad","type":"uint256"},{"indexed":false,"name":"fax","type":"bytes"}],"name":"LogNote","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"authority","type":"address"}],"name":"LogSetAuthority","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"owner","type":"address"}],"name":"LogSetOwner","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"from","type":"address"},{"indexed":true,"name":"to","type":"address"},{"indexed":false,"name":"value","type":"uint256"}],"name":"Transfer","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"owner","type":"address"},{"indexed":true,"name":"spender","type":"address"},{"indexed":false,"name":"value","type":"uint256"}],"name":"Approval","type":"event"}]', 'utf-8')

var contractAddress = '0x86Fa049857E0209aa7D9e616F7eb3b3B78ECfdb0'

var contract = new web3.eth.Contract(abiArray, contractAddress, {from: myAddress})

var rawTransaction = {"from":myAddress, "gasPrice":web3.utils.toHex(2 * 1e9),"gasLimit":web3.utils.toHex(210000),"to":contractAddress,"value":"0x0","data":contract.methods.transfer(toAddress, amount).encodeABI(),"nonce":web3.utils.toHex(count)} 

var transaction = new Tx(rawTransaction)

transaction.sign(privateKey)

web3.eth.sendSignedTransaction('0x' + transaction.serialize().toString('hex'))

// check the balance

contract.methods.balanceOf(myAddress).call().then(function(balance){console.log(balance)})

Once the transaction is sent, you can check it.

If the transaction is not successful wait for a minute and refresh.