Food Ordering System — Microservices

Distributed backend for a simplified food ordering platform built with Java, Spring Boot, Docker, and Kubernetes.

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Team Assignments

Student	Responsibility
1	User Service + Spring Security (JWT)
2	Menu Service
3	Order Service
4	API Gateway + Docker Compose + Kubernetes

Student 4 owns docker-compose.yml and all files under k8s/. The other three must provide a working Dockerfile in their service folder.

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Repository Structure

FoodOrdering/
├── pom.xml                   ← parent POM (do not edit unless agreed)
├── .gitignore
├── docker-compose.yml        ← owned by Student 4
├── README.md
│
├── user-service/             ← Student 1
├── menu-service/             ← Student 2
├── order-service/            ← Student 3
└── api-gateway/              ← Student 4
    k8s/
    ├── user-service/         ← deployment.yml + service.yml (Student 4)
    ├── menu-service/
    ├── order-service/
    └── api-gateway/

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Service Ports

Service	Local Port	Swagger UI
api-gateway	8080	http://localhost:8080/swagger-ui/index.html
user-service	8081	http://localhost:8081/swagger-ui/index.html
menu-service	8082	http://localhost:8082/swagger-ui/index.html
order-service	8083	http://localhost:8083/swagger-ui/index.html

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Databases (PostgreSQL)

Each service uses its own isolated PostgreSQL database. Student 4 decides the host ports in docker-compose.yml.

Service	Database name	Default local port (suggestion)
user-service	userdb	5433
menu-service	menudb	5434
order-service	orderdb	5435
api-gateway	—	no database

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Environment Variables

Each service reads configuration from environment variables. Defaults are set in application.yml for local dev.

user-service, menu-service, order-service

Variable	Default (dev)	Description
DB_HOST	localhost	PostgreSQL hostname
DB_USERNAME	postgres	DB user
DB_PASSWORD	postgres	DB password
JWT_SECRET	(set in application.yml)	Must be ≥32 chars

order-service (additional)

Variable	Default (dev)	Description
MENU_SERVICE_HOST	localhost	Hostname used to call Menu Service
MENU_SERVICE_PORT	8082	Port of Menu Service

api-gateway (additional)

Variable	Default (dev)	Description
USER_SERVICE_HOST	localhost
MENU_SERVICE_HOST	localhost
ORDER_SERVICE_HOST	localhost

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Inter-Service Communication

Client → API Gateway (8080)
              ├─► /users/**    → user-service  (8081)
              ├─► /menu/**     → menu-service  (8082)
              └─► /orders/**   → order-service (8083)

order-service ──REST──► menu-service  (validate + fetch menu items)

Communication uses plain REST/JSON. Order Service calls Menu Service to validate items before creating an order.

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Security

• JWT tokens are issued by user-service on login.
• menu-service and order-service validate the token on every request.
• The JWT_SECRET value must be identical across all three services.
• Roles: CUSTOMER, ADMIN.

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Getting Started

Prerequisites

• Java 17+
• Maven 3.9+
• PostgreSQL (or Docker for containerised databases)

1. Clone the repository

git clone <repo-url>
cd FoodOrdering

2. Validate the Maven multi-module build

mvn validate

All 4 modules (user-service, menu-service, order-service, api-gateway) should resolve without errors.

3. Run your service locally

Create a local PostgreSQL database matching your service's DB name, then run:

# example for user-service
cd user-service
mvn spring-boot:run

Or set env vars explicitly:

DB_HOST=localhost DB_USERNAME=postgres DB_PASSWORD=postgres mvn spring-boot:run

4. Build the project

mvn clean package -DskipTests

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Docker & Kubernetes

docker-compose.yml and all files under k8s/ are owned by Student 4 and are currently empty.
Each other student must provide a working Dockerfile in their service root before Student 4 can wire everything together.

Dockerfile expectations (Students 1–3)

• Multi-stage build: Maven build → JRE runtime.
• Final image exposes the correct port (see table above).
• Reads configuration from environment variables (no hardcoded secrets).

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Git Workflow

Branch	Purpose
main	Stable, deployable code
develop	Integration branch — merge feature branches here
feature/<name>	One branch per feature/task

Workflow:

1. Branch off develop: git checkout -b feature/my-feature develop
2. Open a Pull Request targeting develop.
3. At least one teammate must review before merging.
4. main is updated only at the end of each week with a stable snapshot.

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Order Status Flow

CREATED → CONFIRMED → COMPLETED
               ↓
           CANCELLED

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Tech Stack

Layer	Technology
Language	Java 17
Framework	Spring Boot 3.2
Security	Spring Security + JWT (jjwt 0.12)
Persistence	Spring Data JPA + PostgreSQL
Gateway	Spring Cloud Gateway (reactive)
API Docs	SpringDoc OpenAPI (Swagger UI)
Testing	JUnit 5 + Mockito
Containerisation	Docker
Orchestration	Kubernetes
Build	Maven (multi-module)