Ethereum Smart Contracts

Sample contract which you can compile and deploy to Rinkeby Network.

This is based on Stephen Grider's Udemy Course.

Packages utilized:

• Ganache cli - Test RPC
• Solc - Solidity Compiler
• Web3 - Ethereum JavaScript API
• Truffle Wallet Provider - HD Wallet-enabled Web3 provider
• React - A JavaScript library for building user interfaces

Pre-Requisites To Deploying Contracts To Rinkeby Network

Create Ethereum Account

You must first create an ethereum account to start deploying your contracts.

1. Install Metamask browser extension.
2. Provide a master password and save the 12-word mnemonic (this will be required later).
3. Copy your full account address (e.g. 0x6ed3....) which will be used for getting some ethers.
4. Choose Rinkeby Test Net for your account.

Get Free Ether For Your Account

Deploying your contracts and executing transactions on it will cost you some ethers.

Hence, we need to first add some ethers for your account before proceeding to the next steps.

Rinkeby Faucet can be used to get some free ethers to your account in Rinkeby Network.

Setup Provider

We require a node in the Rinkeby network to deploy our contract.

Register for Infura and get your API key/provider address which we can use to deploy our contracts to the network.

Update Config

In the config.js file update the following properties:

1. config.mnemonic to be updated with the 12-word mnemonic which you got from metamask.
2. config.provider_uri to be updated with the Infura provider URL.

Deploying The Contract In TestRPC & Rinkeby Network

1. Install all the required dependencies

npm install

2. Compile any of the sample contracts inside the contracts folder

npm run compile-contract -- --contract=Inbox

This will generate the ABI (Application Binary Interface) and the bytecode in the bin directory.

3. Run the tests (optional)

npm run test

This will deploy and test the contract using Ganache TestRPC.

4. Deploy the compiled contract to Rinkeby test network. If the contract expects arguments pass them using --arguments option

npm run deploy-contract -- --contract=Inbox --arguments=Hi

Once the contract is deployed to Rinkeby test network, you can use the contract address shown in the console to explore the block using Rinkeby EtherScan.

Alternatively, you can also deploy and interact with your contract using Remix.

Write your own contract and choose Injected Web3 in the Run tab.

This will use your metamask account to deploy contracts and interact with them.

Lottery Contract

Interact with the lottery contract deployed in Rinkeby network at address 0x77EFc56DFf33333Fe864e798B847B827d9691288.

Run the React web app using below command

npm run start-app

Open http://localhost:3000/ in the browser where you have installed the metamask extension and then enter into the lottery!

Note: Metamask will ask for your approval to allow React App to connect to your account. You need to approve the same so that we can send transactions using your account.