🍃 Mongo ERD Generator

Instantly visualize your MongoDB schema relations with zero configuration.

Mongo ERD Generator is a CLI tool that reverse-engineers your MongoDB database to create beautiful, interactive Entity Relationship Diagrams (ERDs). It uses advanced schema analysis to deduce relationships between collections without requiring any manual schema definition.

✨ Features

• 🔮 Automatic Relationship Detection: Intelligent analysis of ObjectId references to infer relations.
• 🖼️ Interactive Visualization: Powered by Mermaid.js and ELK layout engine for clean diagrams.
• 🚀 Zero Config: Just connect and go. No schema files needed.
• 🔍 Deep Inspection: Detects field types, embedded documents, and junction tables.
• 🌐 Web-Based Viewer: Zooms, pans, and exports to PNG directly from your browser.
• 🖥️ Cross-Platform: Works seamlessly on macOS, Windows, and Linux.

📦 Installation

Install globally via npm:

npm install -g mongo-erd-generator

🚀 Usage

Simply run the command in your terminal:

mongo-erd

Interactive Mode (Recommended)

1. Enter your MongoDB connection string (default: mongodb://localhost:27017)
2. Select the database you want to visualize from the list.
3. The tool will generate the ERD and open it in your default browser.

Non-Interactive Options

You can also pass arguments directly for CI/CD or quick access:

mongo-erd --url "mongodb://localhost:27017" --db "my_database" --port 8080

🛠️ How it Works

1. Connects to your MongoDB instance using the provided credentials.
2. Samples documents from each collection to infer schema structure and types.
3. Indexes all ObjectId fields to cross-reference collections.
4. Deduces relationships (1:1, 1:Many, Many:Many) based on reference matching.
5. Generates a Mermaid.js diagram and serves it locally.

🤝 Contributing

We love contributions! This is a passion project aimed at making MongoDB visualization accessible to everyone.

See CONTRIBUTING.md for how to get started.

📝 License

This project is licensed under the ISC License.