Express Modular CLI

A powerful CLI tool for generating modular Express.js projects and components with TypeScript support.

📦 Installation

Install globally via npm to use the CLI from anywhere:

npm install -g express-modular-cli

🚀 Quick Start

1. Create a New Project

exm-cli new my-express-app
cd my-express-app

This command will:

• ✅ Create a complete Express.js project structure
• ✅ Install all required dependencies
• ✅ Initialize git repository with initial commit
• ✅ Set up TypeScript configuration with path aliases
• ✅ Configure development and production scripts

2. Generate Components

Once inside a project, generate individual components:

# Generate a complete user module
exm-cli g module user

# Or generate individual components
exm-cli g controller user
exm-cli g service user
exm-cli g route user

📚 Commands

new <project-name>

Creates a new Express.js project with modern architecture.

exm-cli new my-api

What it does:

• Downloads the latest Express.js boilerplate
• Sets up modular project structure
• Installs dependencies automatically
• Configures TypeScript with path aliases
• Initializes git repository

generate <type> <name> (alias: g)

Generates individual components within an existing project.

# Generate a controller
exm-cli generate controller product
exm-cli g controller product  # Short alias

# Generate a service
exm-cli g service product

# Generate a complete module (all files)
exm-cli g module product

🧩 Component Types

controller

Generates Express.js route controllers with CRUD operations.

exm-cli g controller user

Generated file: src/app/modules/user/user.controller.ts

Features:

• ✅ Complete CRUD operations (create, read, update, delete)
• ✅ Proper error handling with catchAsync
• ✅ Response formatting with sendResponse
• ✅ TypeScript types and interfaces
• ✅ Path aliases for clean imports

service

Creates business logic services with data access layer.

exm-cli g service user

Generated file: src/app/modules/user/user.service.ts

Features:

• ✅ Service layer pattern implementation
• ✅ Interface-based data operations
• ✅ Ready for database integration
• ✅ TypeScript support with proper typing

model

Generates data models with schema definitions.

exm-cli g model user

Generated file: src/app/modules/user/user.model.ts

Features:

• ✅ Mongoose schema definition
• ✅ Model methods and statics
• ✅ TypeScript interface integration
• ✅ Validation rules and middleware

route

Creates Express.js route definitions with middleware.

exm-cli g route user

Generated file: src/app/modules/user/user.route.ts

Features:

• ✅ RESTful route structure
• ✅ Controller method binding
• ✅ Middleware integration points
• ✅ Automatic route registration

validation

Generates input validation schemas.

exm-cli g validation user

Generated file: src/app/modules/user/user.validation.ts

Features:

• ✅ Zod validation schemas
• ✅ Request body validation
• ✅ Parameter validation
• ✅ Type-safe validation rules

interface

Creates TypeScript interfaces and types.

exm-cli g interface user

Generated file: src/app/modules/user/user.interface.ts

Features:

• ✅ TypeScript interface definitions
• ✅ Data transfer objects (DTOs)
• ✅ Type exports for reusability
• ✅ Model integration types

module

Generates all component files for a complete module.

exm-cli g module user

Generated files:

• user.controller.ts - Route controllers
• user.service.ts - Business logic
• user.model.ts - Data models
• user.route.ts - Route definitions
• user.validation.ts - Input validation
• user.interface.ts - TypeScript types

Additional features:

• ✅ Automatic route registration in main router
• ✅ All files properly interconnected
• ✅ Ready-to-use module structure

🏗️ Project Structure

The CLI generates projects with a clean, modular architecture:

my-express-app/
├── src/
│   ├── app/
│   │   ├── modules/
│   │   │   └── user/
│   │   │       ├── user.controller.ts
│   │   │       ├── user.service.ts
│   │   │       ├── user.model.ts
│   │   │       ├── user.route.ts
│   │   │       ├── user.validation.ts
│   │   │       └── user.interface.ts
│   │   ├── routes/
│   │   │   └── index.ts          # Route aggregation
│   │   ├── utils/
│   │   │   ├── catchAsync.ts     # Error handling
│   │   │   ├── sendResponse.ts   # Response formatting
│   │   │   └── ...               # Other utilities
│   │   └── app.ts                # Express app configuration
│   └── server.ts                 # Server startup
├── package.json
├── tsconfig.json                 # TypeScript config with path aliases
├── .env.example
├── .gitignore
└── README.md

⚙️ Smart Features

Context-Aware Generation

The CLI automatically detects your project environment:

Inside Project:

• Uses existing project utilities (catchAsync, sendResponse)
• Imports with path aliases (@/app/utils/...)
• Integrates with existing route structure

Outside Project:

• Includes inline utility functions
• Works as standalone files
• No external dependencies required

Path Alias Support

Generated code uses modern TypeScript path aliases:

// Clean imports with path aliases
import catchAsync from '@/app/utils/catchAsync';
import { sendResponse } from '@/app/utils/sendResponse';

// Module-level relative imports
import { UserService } from './user.service';

Automatic Route Registration

When generating modules or routes, the CLI automatically updates the main router:

// Automatically added to src/app/routes/index.ts
import { UserRoutes } from "../modules/user/user.route";

const moduleRoutes = [
  { path: "/user", route: UserRoutes },
  // Your new routes are automatically registered here
];

🛠️ Prerequisites

• Node.js: Version 16.0.0 or higher
• npm: Comes with Node.js
• Git: Required for project creation (downloads boilerplate)

🔍 Validation & Error Handling

The CLI includes robust validation:

Project Structure Validation

❌ Error: Not in a valid Express project directory

Missing required structure:
  - src/app
  - src/app/modules
  - src/app/routes

Suggestions:
  • Create a new project first using: exm-cli new <project-name>
  • Or run this command from within an existing Express project directory

Component Existence Check

❌ Error: controller user already exists

Input Validation

• Project names must be valid npm package names
• Component names must be valid identifiers
• Component types must be supported

🚨 Troubleshooting

Command Not Found

# Check if installed globally
npm list -g express-modular-cli

# If not found, reinstall
npm install -g express-modular-cli

Permission Issues

# On macOS/Linux, you might need sudo
sudo npm install -g express-modular-cli

# Or configure npm to use a different directory
npm config set prefix ~/.local

Git Issues

# Ensure git is installed and configured
git --version
git config --global user.name "Your Name"
git config --global user.email "[email protected]"

Network Issues

If project creation fails:

• Check internet connection
• Verify access to GitHub
• Try again (temporary network issues)

💡 Tips & Best Practices

1. Always Create Project First

# ✅ Correct workflow
exm-cli new my-api
cd my-api
exm-cli g controller user

# ❌ Wrong - will generate standalone files
exm-cli g controller user  # Outside project

2. Use Module Generation for Complete Features

# ✅ Generates all related files at once
exm-cli g module user

# ⚠️ Manual approach (more work)
exm-cli g controller user
exm-cli g service user
exm-cli g model user
exm-cli g route user
exm-cli g validation user
exm-cli g interface user

3. Follow RESTful Naming

# ✅ Good naming
exm-cli g module user
exm-cli g module product
exm-cli g module order

# ❌ Avoid plurals in component names
exm-cli g module users  # Will create usersController, etc.

📋 Examples

Creating a Blog API

# 1. Create the project
exm-cli new blog-api
cd blog-api

# 2. Generate core modules
exm-cli g module user
exm-cli g module post
exm-cli g module comment

# 3. Generate additional components
exm-cli g controller auth
exm-cli g service email

Creating an E-commerce API

# 1. Create the project
exm-cli new ecommerce-api
cd ecommerce-api

# 2. Generate main modules
exm-cli g module product
exm-cli g module category
exm-cli g module order
exm-cli g module user
exm-cli g module cart

📄 License

MIT License - see LICENSE file for details.

🐛 Issues & Support

Found a bug or need help? Create an issue on GitHub.

Happy coding! 🚀 Build amazing Express.js APIs with the power of modular architecture.