• Node.js (v16 or higher)
• PostgreSQL (v12 or higher)
• npm or yarn

1. Navigate to backend directory:

   cd backend

2. Install dependencies:

   npm install

3. Configure environment:

   cp .env.example .env
   # Edit .env with your database credentials and secrets

4. Create PostgreSQL database:

   CREATE DATABASE client_management;

5. Run migrations:

   npm run migrate

6. Seed database (optional):

   npm run seed

   Default users created:

   • Admin: [email protected] / admin123
   • User 1: [email protected] / user123 (Full access to products & orders)
   • User 2: [email protected] / user123 (Read-mostly, can create orders)

7. Start development server:

   npm run dev

   Server runs on http://localhost:5000

1. Navigate to frontend directory:

   cd frontend

2. Install dependencies:

   npm install

3. Configure environment (optional):

   # Create .env file if you need custom API URL
   REACT_APP_API_URL=http://localhost:5000/api/v1

4. Start development server:

   npm start

   Application runs on http://localhost:3000

backend/
├── src/
│   ├── config/          # Database and app configuration
│   ├── controllers/     # Request handlers
│   ├── middleware/      # Auth, permissions, error handling
│   ├── models/          # Sequelize models
│   ├── routes/          # API routes
│   ├── utils/           # Utility functions
│   ├── validators/      # Input validation schemas
│   └── server.js        # Express app entry point
├── .env.example
└── package.json

frontend/
├── src/
│   ├── api/            # API client and services
│   ├── components/     # Reusable components
│   ├── hooks/          # Custom React hooks
│   ├── layouts/        # Layout components
│   ├── pages/          # Page components
│   ├── store/          # Redux store and slices
│   ├── utils/          # Utility functions
│   ├── App.jsx         # Main app component
│   └── index.jsx       # Entry point
├── public/
└── package.json

• POST /api/v1/auth/register - Register new user
• POST /api/v1/auth/login - Login
• POST /api/v1/auth/logout - Logout
• POST /api/v1/auth/refresh-token - Refresh access token
• GET /api/v1/auth/profile - Get current user profile
• PUT /api/v1/auth/profile - Update profile
• PUT /api/v1/auth/change-password - Change password

• GET /api/v1/users - Get all users
• GET /api/v1/users/:id - Get user by ID
• POST /api/v1/users - Create user
• PUT /api/v1/users/:id - Update user
• DELETE /api/v1/users/:id - Delete user
• GET /api/v1/users/:id/permissions - Get user permissions
• PUT /api/v1/users/:id/permissions - Update user permissions

• GET /api/v1/clients - Get all clients
• GET /api/v1/clients/:id - Get client by ID
• POST /api/v1/clients - Create client
• PUT /api/v1/clients/:id - Update client
• DELETE /api/v1/clients/:id - Delete client

• GET /api/v1/products - Get all products
• GET /api/v1/products/:id - Get product by ID
• POST /api/v1/products - Create product
• PUT /api/v1/products/:id - Update product
• DELETE /api/v1/products/:id - Delete product

• GET /api/v1/orders - Get all orders
• GET /api/v1/orders/:id - Get order by ID
• POST /api/v1/orders - Create order
• PUT /api/v1/orders/:id - Update order
• DELETE /api/v1/orders/:id - Delete order

• GET /api/v1/comments - Get all comments
• GET /api/v1/comments/:id - Get comment by ID
• POST /api/v1/comments - Create comment
• PUT /api/v1/comments/:id - Update comment
• DELETE /api/v1/comments/:id - Delete comment

users

• id, email, password, firstName, lastName, role, isActive, lastLogin, refreshToken

permissions

• id, userId, resource, canCreate, canRead, canUpdate, canDelete
• Unique constraint on (userId, resource)

clients

• id, firstName, lastName, email, phone, address, city, country, postalCode, notes, isActive

products

• id, name, description, sku, price, stockQuantity, category, isActive

orders

• id, orderNumber, clientId, totalAmount, status, notes, createdBy

order_items

• id, orderId, productId, quantity, unitPrice, subtotal

payments

• id, orderId, paymentMethod, amount, status, transactionId, paymentDate, notes

comments

• id, userId, content, entityType, entityId, isEdited

The application implements a sophisticated permission system:

1. Admin Role: Has full access to all resources automatically
2. User Role: Has customizable permissions per resource

1. Login as admin ([email protected] / admin123)
2. Create a new user with limited permissions
3. Logout and login as the new user
4. Verify you can only access permitted resources

1. Login as a user with order creation permissions
2. Navigate to Orders > Create Order
3. Select a client
4. Add products to the order
5. Add one or multiple payment methods
6. Submit the order
7. Verify stock is decremented

Create an order with total $100:

• Payment 1: Cash - $60
• Payment 2: Credit Card - $40
• System validates total equals order amount

NODE_ENV=development
PORT=5000
API_VERSION=v1

DB_HOST=localhost
DB_PORT=5432
DB_NAME=client_management
DB_USER=postgres
DB_PASSWORD=your_password

JWT_SECRET=your_jwt_secret
JWT_EXPIRES_IN=7d
JWT_REFRESH_SECRET=your_refresh_secret
JWT_REFRESH_EXPIRES_IN=30d

CORS_ORIGIN=http://localhost:3000

REACT_APP_API_URL=http://localhost:5000/api/v1