Arithmetic Calculator User API

A microservice responsible for user management, authentication, and account operations within the Arithmetic Calculator ecosystem. Built on AWS Lambda with .NET 8.

Features

• User Management: Registration, authentication, and profile management
• Account Management: Create accounts and manage balances
• Security: JWT-based authentication with refresh token support
• Serverless Architecture: Deployed as AWS Lambda functions

Architecture

This project follows Clean Architecture principles with a clear separation of concerns:

├── Domain         - Core business logic and entities
├── Application    - Use cases, DTOs and service interfaces
├── Infrastructure - External concerns (persistence, security)
└── Presentation   - API endpoints and request handling

Prerequisites

• .NET 8 SDK
• AWS CLI (configured)
• AWS Lambda Tools for .NET

  dotnet tool install -g Amazon.Lambda.Tools

• Docker (optional, for containerized development)

Getting Started

Local Development

1. Clone the repository

   git clone https://github.com/luangrezende/arithmetic-calculator-user-api.git
   cd arithmetic-calculator-user-api

2. Set up environment variables

   # Windows (PowerShell)
   $env:JWT_SECRET_KEY="your-secret-key"
   $env:MYSQL_CONNECTION_STRING="Server=localhost;Database=calculator;User=root;Password=password;"
   $env:PROMOTIONAL_AMOUNT="10"
   
   # Linux/macOS
   export JWT_SECRET_KEY="your-secret-key"
   export MYSQL_CONNECTION_STRING="Server=localhost;Database=calculator;User=root;Password=password;"
   export PROMOTIONAL_AMOUNT="10"

3. Restore dependencies

   dotnet restore

4. Run locally using Lambda Test Tool

   cd src/ArithmeticCalculatorUserApi.Presentation
   dotnet lambda run-server

The API will be accessible at http://localhost:5000.

Docker Development

1. Build the Docker image

   docker build -t arithmetic-calculator-user-api .

2. Run the container

   docker run -p 5000:5000 \
     -e JWT_SECRET_KEY="your-secret-key" \
     -e MYSQL_CONNECTION_STRING="Server=host.docker.internal;Database=calculator;User=root;Password=password;" \
     -e PROMOTIONAL_AMOUNT="10" \
     arithmetic-calculator-user-api

Deployment to AWS Lambda

Manual Deployment

1. Package the application

   cd src/ArithmeticCalculatorUserApi.Presentation
   dotnet lambda package --configuration Release

2. Deploy to AWS Lambda

   dotnet lambda deploy-function ArithmeticCalculatorUserApi

Automated Deployment with GitHub Actions

This project includes a CI/CD pipeline using GitHub Actions. To set up:

1. Add the following secrets to your GitHub repository:

   • AWS_ACCESS_KEY_ID
   • AWS_SECRET_ACCESS_KEY
   • LAMBDA_EXECUTION_ROLE_ARN
   • MYSQL_CONNECTION_STRING
   • JWT_SECRET_KEY

2. See GitHub Actions Setup for detailed configuration.

API Endpoints

Health Check

• GET /user/health - Health check endpoint for monitoring

Authentication

• POST /v1/user/auth/register - Register new user
• POST /v1/user/auth/login - User login
• POST /v1/user/auth/refresh - Refresh authentication token
• POST /v1/user/auth/logout - Logout (invalidate token)

User Profile

• GET /v1/user/profile - Get authenticated user profile

Account Management

• POST /v1/user/account/balance - Add funds to account
• PUT /v1/user/account/balance - Withdraw funds from account

Testing

Run the test suite with:

dotnet test

The project includes unit tests for domain, application, and infrastructure layers.

Configuration

The AWS Lambda configuration is in aws-lambda-tools-defaults.json:

{
  "profile": "default",
  "region": "us-east-1",
  "configuration": "Release",
  "framework": "net8.0",
  "function-runtime": "dotnet8",
  "function-memory-size": 1024,
  "function-timeout": 60,
  "function-handler": "ArithmeticCalculatorUserApi.Presentation::ArithmeticCalculatorUserApi.Presentation.Function::FunctionHandler",
  "function-name": "ArithmeticCalculatorUserApi",
  "function-description": "Lambda function for Arithmetic Calculator User API",
  "package-type": "Zip"
}

Contributing

1. Fork the repository
2. Create your feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add some amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgements

• AWS Lambda
• .NET Core
• AWS Serverless Application Model