ECOMMERCE MICROSERVICES

This repository hosts a sample e-commerce platform demonstrating a microservices architecture using multiple Go services alongside a Python-based Recommender service. The project showcases:

• gRPC communication between services
• Kafka-based event streaming pipeline
• A unified GraphQL API gateway for clients
• Elasticsearch integration for product search

---

📚 Table of Contents

• Overview
• Architecture Diagram
• Services
• Getting Started
• Usage
• Contributing
• Author
• License

---

🧭 Overview

The system comprises several microservices:

• Account (Go): Manages user accounts, authentication, and authorization.
• Product (Go): CRUD for products; indexes product data in Elasticsearch.
• Order (Go): Handles order creation and persistence; publishes events to Kafka.
• Payment (Go): Handles payment operations and sends updates to order microservice
• Recommender (Python): Consumes Kafka events and builds product recommendations.
• API Gateway (Go): A GraphQL service exposing a unified API for front-end clients.

The entire ecosystem is containerized using Docker Compose. Datastores include PostgreSQL, Elasticsearch, and Kafka.

---

🏗 Architecture Diagram

Below is a high-level overview of the system architecture:

Communication Overview

• API Gateway (GraphQL) talks to:

  • Account client → Account server → Postgres
  • Product client → Product server → ElasticSearch + Kafka
  • Order client → Order server → Postgres + Kafka (also communicates with Product service via gRPC)
  • Payment client → Payment service → payment provider + Postgres + Kafka
  • Recommender client → Recommender server (Python) → Postgres (Replica) + Kafka

• Event Flow:

  • Order and Product services act as Kafka producers.
  • Payment service is a Kafka consumer, ingesting product events and saving them in payment provider (DodoPayments).
  • Recommender service is also a Kafka consumer, ingesting order/product events and updating internal state for recommendations.

---

⚙ Services

🧑‍💼 Account Service (Go)

• Responsibilities: Register, login, fetch account data, generate JWT tokens.
• Database: PostgreSQL

📦 Product Service (Go)

• Responsibilities: Product CRUD operations, indexing to Elasticsearch, event publishing to Kafka.
• Database: Elasticsearch

🛒 Order Service (Go)

• Responsibilities: Order creation, price calculation, data persistence, Kafka event publishing.
• Dependencies: Calls product service to retrieve product info.

🧠 Recommender Service (Python)

• Responsibilities: Kafka consumer that builds recommendations based on product/order events.
• Tech Stack: Python + gRPC + PostgreSQL (replica of product DB)

🚪 API Gateway (Go)

• Responsibilities: Unified GraphQL endpoint at /graphql.
• Implementation: Uses gRPC clients for all microservices and schema stitching.

---

🚀 Getting Started

✅ Prerequisites

Before running the project, ensure you have the following installed:

• Docker & Docker Compose
• Git

---

📥 Clone the Repository

  git clone https://github.com/rasadov/EcommerceAPI.git
  cd ecommercemicroservices

---

🐳 Run the Stack

To build and start all services using Docker Compose, run:

# Step 1: Build the base image
docker compose build base

# Step 2: Build and start all services
docker compose up -d --build```

This will start:

• Go microservices (account, order, product, payment, graphql)
• Python-based recommender service
• Databases: PostgreSQL, Elasticsearch
• Kafka + Zookeeper
• GraphQL gateway

---

🌐 Access the API

Once everything is running, open your browser to:

• GraphQL API endpoint:
  http://localhost:8080/graphql

• GraphQL Playground (interactive testing):
  http://localhost:8080/playground

---

📬 Usage (GraphQL)

Below are example GraphQL queries and mutations you can test in the GraphQL Playground.

---

📝 Register a New Account

mutation {
  register(account: {
    name: "Alice"
    email: "alice@example.com"
    password: "secret123"
  }) {
    token
  }
}

---

🔐 Login

mutation {
  login(account: {
    email: "alice@example.com"
    password: "secret123"
  }) {
    token
  }
}

---

➕ Create a Product

mutation {
  createProduct(product: {
    name: "Camera"
    description: "A digital camera"
    price: 99.99
  }) {
    id
    name
  }
}

---

🔍 Query Products

query {
  product(pagination: { skip: 0, take: 10 }) {
    id
    name
    price
  }
}

---

🛒 Create an Order

mutation {
  createOrder(order: {
    products: [
      { id: "PRODUCT_ID", quantity: 2 }
    ]
  }) {
    id
    totalPrice
    products {
      name
      quantity
    }
  }
}

🤝 Contributing

We welcome contributions! To contribute:

Fork the repository

Create a new branch

Commit and push your changes

Open a Pull Request

👤 Author

Rauf Asadov
GitHub: @rasadov
LinkedIn: Rauf Asadov
Email: raufasadov23@gmail.com

🪪 License

This project is licensed under the Apache License 2.0.