Mini CRM Backend

A production-ready REST API backend for a mini Customer Relationship Management (CRM) system built with NestJS, PostgreSQL, and Prisma. This project demonstrates scalable architecture, role-based access control, and efficient database management.

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🚀 Features

🔐 Authentication & Security

• JWT Authentication: Secure stateless authentication using JSON Web Tokens.
• Role-Based Access Control (RBAC): Distinct permissions for ADMIN and EMPLOYEE roles.
• Password Hashing: Industry-standard bcrypt hashing for user passwords.
• Guards: JwtAuthGuard and RolesGuard to protect endpoints.

👤 User Management (Admin)

• Admin-only routes to view system users.
• Capability to upgrade/downgrade user roles.

🏢 Customer Management

• CRUD Operations: Complete Create, Read, Update, Delete functionality.
• Pagination: Optimized list retrieval with page and limit parameters.
• Search: Fuzzy search capability across name, email, and company fields.
• Duplicate Prevention: Validation to prevent duplicate emails/phones.

📋 Task Management

• Workflow: Task lifecycle management (PENDING -> IN_PROGRESS -> DONE).
• Assignment: Tasks assigned to specific Employees for specific Customers.
• Visibility Rules: Employees can only view and update their own assigned tasks.

🛠️ Technical Highlights

• Swagger Documentation: Automated, interactive API documentation.
• Input Validation: Robust DTO validation using class-validator.
• Global Error Handling: Standardized error responses via strict Exception Filters.
• Logging: Request duration tracking via Interceptors.
• Docker Support: Containerized setup for easy deployment.

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🛠️ Tech Stack

• Framework: NestJS (Node.js/TypeScript)
• Database: PostgreSQL
• ORM: Prisma
• Documentation: Swagger / OpenAPI
• Containerization: Docker & Docker Compose

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📋 Prerequisites

• Node.js (v18+)
• PostgreSQL (v12+)
• Git

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🔧 Installation & Setup

1. Clone the repository

   git clone https://github.com/Shubh-Raj/CRM.git
   cd CRM
   cd mini-crm-backend

2. Install dependencies

   npm install

3. Configure Environment Create a .env file in the root directory:

   DATABASE_URL="postgresql://postgres:YOUR_PASSWORD@localhost:5432/mini_crm?schema=public"
   JWT_SECRET="your-secure-secret-key"

4. Setup Database

   # Create database (if not exists)
   # Run migrations
   npx prisma migrate dev

5. Start the Server

   npm run start:dev

   The server will start at http://localhost:3000.

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🧪 Testing the Application

Option 1: Automated Test Script (Recommended)

We have included a PowerShell script that automatically tests the entire flow (Register -> Login -> Create Customer -> List Customers).

Run in terminal:

.\test_api.ps1

Option 2: Interactive Swagger UI

Visit http://localhost:3000/api to see the interactive documentation.

1. Register: POST /auth/register (Role: ADMIN)
2. Login: POST /auth/login -> Copy accessToken
3. Authorize: Click green "Authorize" button -> Paste Token
4. Test Endpoints: Try GET /customers or POST /tasks

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🐳 Docker Deployment

To run the entire stack (App + Postgres) using Docker:

docker-compose up --build

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📂 Project Structure

src/
├── auth/          # Authentication logic (Guards, Strategies)
├── common/        # Shared resources (Filters, Interceptors, Constants)
├── customers/     # Customer management domain
├── tasks/         # Task management domain
├── users/         # User management domain
├── prisma/        # Database connection service
└── main.ts        # Entry point

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👤 Author

Shubh Raj