Overview

This is a basic messaging web-app which uses an Ethereum blockchain as a model.

Prerequisites

• Yarn
• Geth

Running the web-app

To run the web-app, you'll need to follow these steps:

• Initialize the blockchain with Geth
• Initialize the Ethereum network with Geth
• Start the lazy miner
• Install packages with yarn
• Run the dev server

Initialize the blockchain

To initialize the blockchain in the folder blockchain, run the following command:

geth -datadir ./blockchain init ./genesis.json

Initialize the Ethereum network

To initialize the network, run the following command (replacing <device-name> with your device's name):

geth --datadir ./blockchain --networkid 7314 --ws --wsorigins "http://localhost:8080,http://<device name>" --wsapi="eth,web3,personal,miner" --gasprice 0

This needs to be running whenever you start the web-app.

Start the lazy miner

To start the lazy miner, run the following command:

geth attach ws://localhost:8546 --preload ./lazyMine.js

This starts a miner which only mines when new transactions are available. This should be running in the background whenever you use the web-app, or new transactions will not be committed to the blockchain and thus won't appear on the app.

Install packages

Use the following command to install the required packages:

yarn install

Run the dev server

Use the following command to run the dev server:

yarn run start