E-commerce Application Backend

This is the backend for an e-commerce application, designed to handle various aspects of an online store, including user authentication, product management, and discount handling. It's built with a focus on modularity and common best practices.

Technologies Used

This project leverages the following key technologies and libraries:

Backend Framework:

• Node.js: Asynchronous event-driven JavaScript runtime environment.
• Express.js: Fast, unopinionated, minimalist web framework for Node.js.

Database:

• MongoDB: A NoSQL document database used for storing application data.
• Mongoose: An ODM (Object Data Modeling) library for MongoDB and Node.js, providing a schema-based solution to model application data.

Authentication & Security:

• bcrypt: Library to help hash passwords.
• jsonwebtoken: JSON Web Token implementation for Node.js, used for secure authentication.
• helmet: Helps secure Express apps by setting various HTTP headers.
• compression: Node.js compression middleware.
• morgan: HTTP request logger middleware for Node.js.

Utilities:

• dotenv: Loads environment variables from a .env file.
• lodash: A modern JavaScript utility library delivering modularity, performance, & extras.
• slugify: Generates URL-friendly slugs from strings.
• prettier: An opinionated code formatter used for maintaining consistent code style.

Project Structure

The project follows a modular structure to ensure maintainability and scalability:

• server.js: The entry point of the application, responsible for starting the server and connecting to the database.
• src/app.js: Configures the Express application, applies middleware (morgan, helmet, compression, express.json, express.urlencoded), initializes the database connection, and registers API routes. It also includes global error handling.
• src/configs/config.mongodb.js: Manages development and production database configurations, including port, username, password, and cluster details.
• src/dbs/init.db.js: Handles the MongoDB connection using Mongoose, including debug mode for development and a singleton pattern for the database instance.
• src/helpers/check.connect.js: Provides utility functions to check database connection status and monitor server overload.
• src/models/: Defines Mongoose schemas for various entities like Shop, Product, ApiKey, KeyToken, Discount, and Inventory.
  • product.model.js also defines sub-schemas for Clothing, Electronic, and Furniture products, demonstrating a design pattern for product variations.
• src/models/repositories/: Contains repository files (discount.repo.js, inventory.repo.js, product.repo.js) that abstract database interactions, keeping services clean from direct Mongoose calls.
• src/services/: Implements the business logic for different modules (e.g., access.service.js for authentication, product.service.js for product management, discount.service.js for discount operations, keyToken.service.js for JWT key management).
• src/routes/: Defines API routes and links them to the corresponding controller functions.
  • src/routes/index.js acts as the main router, applying API key and permission checks globally.
• src/auth/: Contains authentication-related utilities and middleware (authUtils.js for token creation and authentication, checkAuth.js for API key and permission checks).
• src/controllers/: Houses the controllers (access.controller.js, product.controller.js) that handle incoming requests, interact with services, and send responses.
• src/core/: Defines custom error and success response classes (error.response.js, success.response.js) for consistent API responses.
• src/utils/: Contains general utility functions (index.js for data manipulation, createKeyPair.js for key generation, httpStatusCode.js, reasonPhrases.js, statusCodes.js for HTTP status handling).

Features

Authentication & Authorization

• Shop Registration (/v1/api/shop/signup): Allows new shops to register with a name, email, and password. Passwords are BCRYPT hashed.
• Shop Login (/v1/api/shop/login): Authenticates existing shops and generates an access token and a refresh token for subsequent API calls. Public and private keys are used for JWT signing and verification.
• Logout (/v1/api/shop/logout): Invalidates the current session's tokens, removing the key store entry from the database.
• Refresh Token Handling (/v1/api/shop/handleRefreshToken): Allows clients to obtain a new access token and refresh token pair using an existing refresh token, with checks for token reuse.
• API Key Verification: All API routes are protected by an API key check (x-api-key header).
• Permission Control: Routes are protected by a permission middleware that checks if the x-api-key has the required permissions (e.g., '0000' for product management).
• Role-Based Access: Shops can have roles such as SHOP, WRITER, EDITOR, and ADMIN.

Product Management

• Create Product (/v1/api/product): Allows authenticated shops to create new products. Supports different product types: Electronic, Clothing, and Furniture, using a Factory and Strategy design pattern.
• Update Product (/v1/api/product/:productId): Enables shops to update product details.
• Publish/Unpublish Product (/v1/api/product/publish/:id, /v1/api/product/unpublish/:id): Shops can change the isDraft and isPublish status of their products.
• Get Draft Products (/v1/api/product/drafts/all): Retrieves a list of all products in draft status for a given shop.
• Get Published Products (/v1/api/product/published/all): Retrieves a list of all published products for a given shop.
• Search Products (/v1/api/product/search/:keySearch): Allows users to search for products by keywords in product name and description.
• Get All Products (/v1/api/product): Fetches a paginated list of all published products, with options for sorting and filtering.
• Get Single Product (/v1/api/product/:product_id): Retrieves details for a specific product by its ID.

Discount Management

• Create Discount Code: Allows shops to generate various types of discount codes (fixed amount or percentage), with configurable start/end dates, max uses, min order value, and product applicability.
• Update Discount Code: Enables modification of existing discount codes.
• Get All Discount Codes by Shop: Retrieves a list of active discount codes available for a specific shop.
• Get All Products by Discount Code: Fetches products to which a specific discount code can be applied.
• Calculate Discount Amount: Determines the actual discount value for a given set of products and discount code, considering minimum order value and usage limits.

Inventory Management

• Insert Inventory: Automatically adds product stock to the inventory collection upon product creation.

Prerequisites

Before running this application, ensure you have the following installed on your machine:

• Node.js: v18 or later.
• npm: v10 or later.
• MongoDB: Installed and running locally, or access to a MongoDB Atlas cluster.

Installation

Follow these steps to set up and run the application:

1. Clone the repository:

   git clone https://github.com/Tao242dn/ecommerce-app.git

2. Navigate to the project directory:

   cd ecommerce-app

3. Install dependencies:

   npm install

4. Configure environment variables: Rename .env-example to .env in the root directory of the project and add the necessary environment variables for your MongoDB connection (e.g., DEV_MONGODB_USERNAME, DEV_MONGODB_PASSWORD, DEV_MONGODB_CLUSTER).

5. Start the server:

   npm run dev

   The server will start running on the port configured in your .env file (defaulting to 4000 for development).

Scripts

• npm run dev: Starts the server with --watch for development, automatically restarting on file changes.
• npm run format: Formats the code using Prettier.

Code Formatting

This project uses Prettier for code formatting. The configuration is defined in .prettierrc.json. You can run npm run format to automatically format your code.

Environment Variables

The application relies on environment variables for configuration. A .env-example file is provided as a template. You should create a .env file based on this example and fill in your specific values.

Example .env content:

DEV_APP_PORT=4000
DEV_MONGODB_USERNAME=your_dev_username
DEV_MONGODB_PASSWORD=your_dev_password
DEV_MONGODB_CLUSTER=your_dev_cluster_name

PRO_APP_PORT=3000
PRO_MONGODB_USERNAME=your_pro_username
PRO_MONGODB_PASSWORD=your_pro_password
PRO_MONGODB_CLUSTER=your_pro_cluster_name

NODE_ENV=dev

Replace your_dev_username, your_dev_password, your_dev_cluster_name, etc., with your actual MongoDB credentials and cluster details.