Agora Blockchain

Agora Blockchain

Prerequisites (only for contributing)

• Basic familarity with Git, NodeJS and npm.
• Basic familarity with ReactJS, React context APIs, if working on frontend part.
• Basic familarity with Blockchain, Solidity and Hardhat, if working on blockchain part.

Requirements

• NodeJS >= 10.16 and npm >= 5.6 installed.
• Git installed in the system.
• Hardhat, which can be installed globally with npm install --save-dev hardhat
• Metamask extension added to the browser.

Development Guide

Clone the repository

git clone https://gitlab.com/aossie/agora-blockchain/

Switch to develop branch

git checkout develop

The frontend code is inside the client directory, whereas the smart contracts (solidity) is present inside server folder. You may proceed to client folder if you are here for enhancing frontend part of the Agora Blockchain. Else you can proceed to server folder for enhancing the efficiency or introducing new features in the blockchain part of the Agora.

Whatever dependencies you need for frontend should be saved in their local package.json and not in the global one. This would ensure that a developer who only want to contribute to blockchain code, should not install unneccessary frontend dependencies and vice-versa.

Setting up client side

Frontend code is present inside the client folder. Thus, the dependencies required for frontend are listed in the local package.json of client folder. You can install only the client-side dependencies using the following command.

Install client-side dependencies

npm run install-client --force

or

cd client
npm install

Start frontend

For development purpose we will run this command to start our client react app.

npm run client

or

cd client
npm start

Build production for client

Only required while deploying frontend to some hosting services like AWS, Heroku, GCP etc.

This will create production build folder inside the client directory with the minified code of frontend. The production build will be served using server.js file inside the client folder.

npm run build

Deploying the repository to Heroku would automatically serve production build of the client side. This is because, Heroku uses npm run build for deploying our application. Once the build is complete, it uses the npm start command. In the package.json file of root directory, you can see node client/server.js command against start script. This will serve the minified files from build direcotry.

Setting up Hardhat

Smart contracts or blockchain codes and necessary config files for developing, testing and deploying them are present inside server directory. Inside the server folder, there is contracts directory which stores Agora Blockchain's business logic i.e. the smart contracts. migrations folder contains files for migrating smart contracts to the blockchain network. Go through these smart contracts and start contributing.

About smart contracts

We use Hardhat for editing, compiling, debugging and deploying your smart contracts and dApps, all of which work together to create a complete development environment. Compiled smart contracts or build files are then stored inside the /artifacts/contracts directory. You need to copy the required files to the frontend after compiling.

Install server-side dependencies

npm run install-server

or

cd server
npm install

Now move inside server folder for the next steps.

Compiling smart contracts

If we have altered the code within our Solidity files (.sol) or made new ones or just want generate build files for the client, we need to run npx hardhat compile in the terminal. Compiled files are generated inside /artifacts/contracts/File_name/.

npx hardhat compile

Create a .env file

For deploying smart contracts on a blockchain network we need two things: A node connected to the network through which we will make RPC calls and an account with few coins, to cover the cost of deployment. Infura provides us the node for Ethereum network. So register there and put the Infura's API key inside of the .env file, like shown below.

MNEMONIC="<YOUR_SEED_GOES_HERE>"
KEY="<YOUR INFURA KEY GOES HERE>"

Also save your wallet's mnemonic phrase against the MNEMONIC in .env file, and don't forget to fund the account corresponding to that mnemonic. There are several faucets available to fund your account with test tokens.

Never share or commit your .env file. It contains your credentials like mnemonics and API key. Therefore, it is advised to add .env to your .gitignore file.

Deploying smart contracts

You can deploy the smart contracts in the localhost network following these steps:

• Start a local node

npx hardhat node

• Open a new terminal and deploy the smart contract in the localhost network.

npx hardhat run --network localhost scripts/deploy.js

The above line will print the contract addresses which are deployed, mentioned in deploy.js.

Replace the contract addresses printed in the terminal with the contract addresses hard coded in the frontend files.