🍽️ Meal Tracker API

A RESTful backend application that allows users to search foods, register consumed meals, and calculate daily nutrient intake.

This project was built to practice and demonstrate:

• Spring Boot
• Spring Data JPA
• JWT Authentication
• External API Consumption using WebFlux
• Pagination
• Custom JPQL queries
• Date filtering with LocalDateTime
• Data aggregation (daily nutrients)
• Docker usage
• Integration testing

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🚀 Features

🔎 Search for a Specific Food

Search foods using the USDA FoodData Central API.

Endpoint

GET /foods/search?name=chicken

Example Response

[
  {
    "name": "Chicken Breast",
    "calories": 165,
    "protein": 31,
    "fat": 3.6,
    "carbohydrates": 0
  }
]

Register Consumed Food

Allows a user to register a consumed meal, including quantity and timestamp.

Endpoint: POST /entries

Request Body

{
  "foodName": "Apple",
  "quantity": 2
}

The system:

• Searches the food via USDA API

• Persists a FoodEntry

• Associates nutrients

• Links it to the authenticated user

Get All Food Entries for a Specific Day

Retrieve all meals consumed by a user on a specific date.

Endpoint: GET /entries?date=2026-02-17

Internal Logic

Converts LocalDate into:

2026-02-17T00:00:00

2026-02-18T00:00:00

Filters using a time range query

Supports pagination

Example Response

{
  "content": [
    {
      "foodName": "Apple",
      "quantity": 2,
      "consumedAt": "2026-02-17T14:30:00"
    }
  ],
  "page": 0,
  "size": 10,
  "totalElements": 1
}

Get Total Nutrients for a Day

Calculates total nutrients consumed on a given date.

Endpoint: GET /entries/nutrients?date=2026-02-17

Logic

Fetch all entries for the day

Iterate over nutrients of each food

Group nutrients by name

Sum total values

Example Response

[
  {
    "name": "Protein",
    "unitName": "g",
    "totalValue": 120.5
  },
  {
    "name": "Carbohydrates",
    "unitName": "g",
    "totalValue": 85.0
  }
]

Architecture

Layered architecture: Controller → Service → Repository → Database

• Controller: Handles HTTP requests

• Service: Business logic

• Repository: JPA data access

• Entities: Domain model

Security

• JWT-based authentication

• Stateless session management

• Role-based authorization

• Protected endpoints

🛠 Technologies

• Java 21

• Spring Boot

• Spring Data JPA

• PostgreSQL

• Spring Security

• Redis (optional caching)

• Docker

• USDA FoodData Central API

⚙️ Environment Variables

The application requires the following environment variables:

Variable	Description
USDA_API_KEY	API key for USDA FoodData Central
DB_URL	PostgreSQL connection URL
DB_USERNAME	Database username
DB_PASSWORD	Database password
JWT_SECRET	Secret used to sign JWT tokens

🐳 Running with Docker

If using Docker Compose:

docker compose up --build

Make sure environment variables are defined in .env file or Docker Compose environment section

🧪 Testing

• Unit tests with JUnit and Mockito