Expense Tracker API

A REST-ful API designed to manage personal financial expenses and categories. This project is built using Spring Boot and Spring Data JPA, focusing on core CRUD operations and a professional database design.

Features

• Category Management (CRUD): Add, view, update, and delete spending categories
• Record expenses with details like description, amount and date, linking each to a specific category
• Uses Decimal(10, 2) for amount to ensure accurate financial calculations.
• Auditing: Automatic timestamping for creation and last update (createdAt, updateAt).
• Unit tests (services).
• Intgration tests (controllers).
• API Documentation with Swagger UI.
• Exception handling with meaningful error responses.
• Input validation to ensure data integrity using Data Transfer Objects(DTOs).
• CI pipeline with GitHub Actions for automated testing and building.

Tech Stack

• Language: Java 17
• Framework: Spring Boot 3.2.0
• Data Access: Spring Data JPA
• Database: PostgresSQL
• Testing: JUnit 5, Mockito
• API Documentation: Springdoc OpenAPI (Swagger UI)

Database Schema

The application uses a normalized database structure consisting of two tables with a One-to-Many relationship (one Category to many Expenses).

Getting Started

Prerequisites

• JDK 17 or later
• Maven 3.6+
• PostgresSQL instance running

1. Clone the repository

git clone https://github.com/SymonMuchemi/expense_tracker_api
cd expense_tracker_api

2. Configure the database

spring.datasource.url=jdbc:postgresql://localhost:5432/expense_tracker_db
spring.datasource.username=your_username
spring.datasource.password=your_password
spring.jpa.hibernate.ddl-auto=update

3. Build and Run

Run the application using the Spring Boot Maven plugin:

./mvnw clean install
./mvnw spring-boot:run

Swagger Documentation:

http://localhost:8080/swagger-ui/index.html#