Project structure

We will build the following strucuture:

├── app
│   ├── index.html
│   └── js
│       └── app.js
├── build
│   ├── app
│   │   ├── index.html
│   │   └── js
│   │       └── app.js
│   └── contracts
│       ├── ConvertLib.json
│       ├── Migrations.json
│       └── Splitter.json
├── contracts
│   ├── ConvertLib.sol
│   ├── Migrations.sol
│   └── Remittance.sol
├── migrations
│   ├── 1_initial_migration.js
│   └── 2_deploy_contracts.js
├── package.json
├── README.txt
├── test
│   ├── metacoin.js
│   └── TestMetacoin.sol
├── truffle.js
└── webpack.config.js

Install base packages

npm init
npm install --save-dev webpack
npm install --save-dev webpack-dev-server
npm install --save-dev file-loader
npm install --save-dev truffle
npm install --save-dev ethereumjs-testrpc
npm install --save truffle-contract
npm install --save web3@0.20.1 # 1.0.0-beta doesn't work at the time of writing
npm install --save jquery

This will install the following dependencies:

Setup a truffle project

In the newly created directory, run:

./node_modules/.bin/truffle init

Note: This doesn't seem to work behind a proxy.

Write code

Our javascript entry point is app/js/app.js. This should be the main javascript file which requires all other modules.

Use the following template for the file app/js/app.js:

TODO: Use strict

TODO: Linter

// Tell webpack to copy the index.html file to the build directory

const Web3 = require('web3');
const truffleContract = require("truffle-contract");
const $ = require("jquery");

var web3;
var Contract;

function init_contract() {
    // Supports Mist, and other wallets that provide 'web3'.
    if (typeof web3 !== 'undefined') {
        // Use the Mist/wallet/Metamask provider.
        web3 = new Web3(web3.currentProvider);
    } else {
        // Your preferred fallback.
        web3 = new Web3(new Web3.providers.HttpProvider('http://localhost:8545')); 

    // Use JSON info from 'truffle compile' to load the contract
    Contract = truffleContract(require("../../build/contracts/Contract.json")); 

    // To help with debugging we expose web3 and the contract as global vars. This way we can use them from the browser console
    window.Contract = Contract;
    window.web3 = web3;

$(document).ready(function() {

    // Call your JS from here

Use the following template for the file app/index.html:

<!doctype html>

<html lang="en">
        <meta charset="utf-8">

        <meta name="description" content="TODO">
        <meta name="author" content="TODO">

        <!--[if lt IE 9]>
        <script src=""></script>

        <!-- HTML code goes here -->
        <script src="js/app.js"></script>

Deploy the smart contract

During the development we use testrpc. This is a in-memory version of the Ethereum blockchain. Start it with:

./node_modules/.bin/testrpc -d

The -d gives us deterministic accounts. This simplifies testing because we can hardcode the accounts.

Modify migrations/2_deploy_contracts.js to deploy your own contracts instead of the default MetaCoin contract.

Run the following to deploy the smart contracts to testrpc:

./node_modules/.bin/truffle migrate --reset

Run test for smart contracts

Test are stored in ./tests and are written in mochajs. To run them, make sure testrpc is running and start the tests with:

./node_modules/.bin/truffle test

Configure webpack

Create a new file ./webpack.config.js with the following content:

var path = require('path');

module.exports = {
  entry: './app/js/app.js',
  output: {
    filename: 'app.js',
    path: __dirname + '/build/app/js'
  module: {
    loaders: []

Start development http server

Start the webpack-dev-server. This server serves and updates the compiled javascript file from memory and all the files in content-base:

./node_modules/.bin/webpack-dev-server --open --content-base build/app/ --output-public-path js

Again, to save us typing we already put that in the package.json under the scripts section. Run it with:

And run it with:

npm start

Build the project

TODO: Uglify/Minify

Compile the smart contracts:

./node_modules/.bin/truffle compile

Again, to save us typing we already put that in the package.json under the scripts section. Run it with:

npm run build