E-Commerce Order Management System

This is a simple e-commerce application built with Flask and SQLAlchemy for managing customers, products, and orders. The system includes customer registration, product and order management, order history viewing, and order status updating.

Table of Contents

• Setup
• Database Configuration
• Features
• API Endpoints
• Using the Application

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Setup

1. Clone the repository:

   git clone https://github.com/your-repo/ecommerce-app.git
   cd ecommerce-app

2. Install the required packages: Ensure you have Python 3 and pip installed, then run:

   pip install -r requirements.txt

3. Configure Environment Variables: Create a .env file in the project root with your database credentials:

   username=your_mysql_username
   password=your_mysql_password
   

Database Configuration

1. Set up the MySQL Database:

   • Ensure you have a MySQL database named ecommerce.
   • Configure your .env file with the correct credentials.

2. Initialize the Database: In the project directory, run:

   flask db init
   flask db migrate -m "Initial migration"
   flask db upgrade

Features

• Customer Management: Register new customers with basic information.
• Product Management: Products with stock, price, and other details.
• Order Management: Place new orders for customers, with items and quantities.
• Order History: View the order history of each customer.
• Order Status Update: Change the status of an order (e.g., pending, shipped, delivered, canceled).

API Endpoints

1. Homepage
   Endpoint: GET /
   Description: Displays the application homepage with forms to interact with the API.

2. Register Customer
   Endpoint: POST /register_customer
   Description: Registers a new customer.
   Request JSON:

   {
     "name": "Customer Name",
     "email": "email@example.com",
     "phone_number": "1234567890"
   }

3. Place Order
   Endpoint: POST /place_order
   Description: Places an order for a customer with multiple items.
   Request JSON:

   {
     "customer_id": 1,
     "items": [
       {
         "product_id": 101,
         "quantity": 2
       },
       {
         "product_id": 102,
         "quantity": 5
       }
     ]
   }

4. Order History
   Endpoint: GET /order_history/<customer_id>
   Description: Streams the order history for a customer.

5. Update Order Status
   Endpoint: PATCH /update_order_status
   Description: Updates the status of a specific order.
   Request JSON:

   {
     "order_id": 1,
     "status": "shipped"
   }

Using the Application

1. Start the Flask Application:

   python app.py

   The application will run on http://localhost:5000.

2. Access the Homepage: Open a web browser and navigate to http://localhost:5000 to view the main page with forms for registration, order placement, and status updating.

3. Register a Customer:

   • Fill in the name, email, and phone number in the "Register Customer" form.
   • Submit to register a new customer.

4. Place an Order:

   • Enter the customer ID, then specify multiple product IDs and quantities.
   • Submit to place the order.

5. View Order History:

   • Visit /order_history/<customer_id> in the browser (replace <customer_id> with an actual ID) to view past orders.

6. Update Order Status:

   • Enter an order ID and select the new status in the "Update Order Status" form.
   • Submit to update the order's status.

Additional Notes

• Decorator for Stock Validation: validate_stock decorator verifies if there’s sufficient stock before placing an order.
• Lambda for Discounts: Orders with more than 10 items receive a 10% discount using a lambda function.
• Generator for Order History: Streams order history with a generator function to efficiently handle large datasets.