GO Backend - Smart Contract

A DApp manages employee attendance and details using Golang and Solidity. It leverages blockchain tech for transparency and security. Golang handles the backend, while Solidity creates smart contracts for recording and validating attendance on the blockchain.

Docs

• Overview System
• API Design:
  • Postman API Online
  • Postman JSON

🛠 Built With

Run Locally

Environment

• Go: go1.22.2 linux/amd64
• Docker: 25.0.3, build 4debf41
• Node: v18.18.0
• Solc: 0.8.25+commit.b61c2a91.Linux.g++
• Abigen: 1.14.3-stable
• Migrate 4.17.1

Clone the project.

git clone https://github.com/hndev2404/interview_prj
cd interview_prj

Smart Contract compilation & ABI

Install sol

sudo apt-get install solc

Install abigen.

go install github.com/ethereum/go-ethereum/cmd/abigen

Compile Daemon

Very simple compile daemon for Go

go install github.com/githubnemo/CompileDaemon

Deploy Smart Contract

1. Generate Go binding for contract.

   make init-contract

2. Update .env

   BC_DIAL_CLIENT Dial connects a client to the given URL.

   BC_ACCOUNT_PRIVATE_KEY The account using for deploy smart contract (Owner)

   BC_DIAL_CLIENT=<dial client>
   BC_ACCOUNT_PRIVATE_KEY=<private key>

3. Deploy smart contract

   make deploy-contract

   After the deploy succeed we will get address of contract in folder ./logs with format name: ./logs/deploy_smart_contract_YYYY-MM-DD_HH:mm:ss.log

   Copy the contract address from the terminal and paste it in .env.

   BC_CONTRACT_ADDRESS=<contract address>

   For example:

   2024/05/16 22:00:31 Transaction has been committed!!
   2024/05/16 22:00:31 --------------------------------
   2024/05/16 22:00:31 Contract Address: 0xc2Fb27e49491ceeB451403c19b783a78F7E903dD
   2024/05/16 22:00:31 -----------------
   2024/05/16 22:00:31 Transaction Hash: 0xfd8b30e0c96b2606af207dd98b1f6fbc58514285286ca5b589ed0209c7c163a9
   2024/05/16 22:00:31 -----------------
   

Start Application

1. Start Postgres & Adminer for Database

   make up

2. Init database

   make migrate up

   Or execute SQL queries directly at migrations/init.sql

3. Run app on local

   make dev

   The application will run on PORT has been defined in .env.