# Course Content Service

The **Course Content Service** is a microservice responsible for managing courses, modules, and lessons in the EdTech platform.  
It provides **REST** and **gRPC APIs** to create, update, retrieve, and manage study materials.  
This service uses **MongoDB** as its primary data store due to the flexible and schema-less nature of course content.

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## 🚀 Features
- Manage Courses, Modules, and Lessons
- Store metadata for study materials (title, description, tags, difficulty, etc.)
- RESTful APIs (Swagger/OpenAPI support)
- gRPC endpoints for inter-service communication
- Structured logging and middleware support
- Unit tests, integration tests, and load tests
- Dockerized & ready for Kubernetes deployment

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## 🛠️ Tech Stack
- **Language:** Go (Golang)
- **Framework:** Gin / Fiber (REST APIs)
- **Database:** MongoDB
- **gRPC:** Protobuf for inter-service contracts
- **Logging:** Structured logging (Zap/Logrus)
- **Testing:** Go test, mocks, load tests
- **Containerization:** Docker, Helm charts (for deployment)

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## 📂 Project Structure
```bash
course-content-service/
├── apis/                       # Swagger/OpenAPI specs
├── cmd/
│   └── server/                 # Entry point (main.go)
├── config/
│   ├── config.yaml             # Default configs
│   └── loader.go               # Loads env/config
├── env/                        # Env files (.env, dev.env, prod.env)
├── handler/                    # API layer (controllers)
│   ├── http/                   # REST controllers
│   └── grpc/                   # gRPC handlers
├── model/                      # Domain models (Course, Module, Lesson)
├── repository/                 # Database layer
│   ├── mongo/                  # MongoDB implementation
│   └── mock/                   # Mocks for testing
├── service/                    # Business logic layer
│   ├── course/                 # Course service
│   ├── lesson/                 # Lesson service
│   └── test/                   # Unit tests
├── server/                     # Server bootstrap
│   ├── api/                    # API setup (Gin/Fiber routes)
│   └── props/                  # Server props (ports, timeouts)
├── middleware/                 # Logging, tracing, auth, rate limiting
├── pkg/                        # Shared package (db conn, cache conn)
│   ├── db/
│   │   └── mongo.go            # Mongo connection
│   └── logger/                 # Structured logging setup
├── scripts/                    # Local scripts (migrations, seeding)
├── test/                       # Integration & load tests
│   ├── api/
│   └── load/
├── swagger/                    # Swagger spec + docs
├── Dockerfile
├── Makefile
└── go.mod

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⚡ Getting Started

Prerequisites

• Go 1.21+
• MongoDB
• Docker
• Make

1️⃣ Clone Repository

git clone https://github.com/your-org/course-content-service.git
cd course-content-service

2️⃣ Setup Environment

Create a .env file or use existing env/dev.env:

MONGO_URI=mongodb://localhost:27017
DB_NAME=course_service
PORT=8080

3️⃣ Run Locally

go mod tidy
go run cmd/server/main.go

4️⃣ Run with Docker

docker build -t course-content-service:latest .
docker run -p 8080:8080 --env-file=env/dev.env course-content-service:latest

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📜 API Documentation

• REST APIs documented with Swagger → http://localhost:8080/swagger/index.html
• gRPC APIs defined in /apis/proto/course.proto

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🧪 Testing

make test

• Unit Tests → service/test/
• Integration Tests → test/api/
• Load Tests → test/load/

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📦 Deployment

• Containerized using Docker
• Kubernetes-ready via Helm charts (/helm/course-content/)
• Supports CI/CD with GitHub Actions / Jenkins pipelines

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📌 Future Enhancements

• Add content versioning (track updates to lessons/modules)
• Integrate with Elasticsearch for fast course search
• Add GraphQL API layer
• Caching with Redis for frequently accessed course data

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👨‍💻 Maintainers

• Arjun Singh
• Team/ArjunDev17

Kafka Learning Roadmap

This repository is being enhanced step by step into a production-ready Event-Driven microservice.

Phase 1 - Kafka Producer ✅

• Create Course API
• Store Course in MongoDB
• Publish course.created event to Kafka
• Understand Producers, Topics, and Event Contracts

Phase 2

• Notification Service (Kafka Consumer)

Phase 3

• Subscriber Management

Phase 4

• Notification Worker Pool

Phase 5

• Retry Topics

Phase 6

• Dead Letter Topic (DLT)

Phase 7

• Consumer Groups

Phase 8

• Partitions

Phase 9

• Ordering Guarantees

Phase 10

• Production Deployment