NestJS Dependency Analyzer

A command-line tool for analyzing and visualizing dependencies in NestJS applications. This tool parses your NestJS modules and creates visual representations of their relationships, helping you understand the architecture of your application.

Features

🔍 Analyzes NestJS module dependencies
📊 Generates dependency graphs in DOT format
🎨 Visualizes module relationships using Graphviz
📝 Outputs detailed module information in JSON format
🔄 Supports circular dependency detection
📦 Tracks imports, providers, and controllers

Prerequisites

Node.js (v14 or higher)
npm or yarn
Graphviz (optional, for visualization)

Installing Graphviz

For generating visual graphs, you'll need to install Graphviz:

Windows (using Chocolatey):

choco install graphviz

macOS (using Homebrew):

brew install graphviz

Ubuntu/Debian:

sudo apt-get install graphviz

Installation

# Clone the repository
git clone https://github.com/ChuloWay/nestjs-dependency-analyzer.git

# Install dependencies
cd nestjs-dependency-analyzer
npm install

# Build the project
npm run build

# Link globally (optional)
npm link

Usage

Basic Command

npm run analyze -- [options]

Options

Options:
  -p, --path <path>      Project path (default: current directory)
  -f, --format <format>  Output format (json|dot) (default: "json")
  -d, --depth <depth>    Dependency resolution depth (default: "2")
  -o, --output <output>  Output file path
  -h, --help            Display help information

Examples

Analyze current directory and output JSON:

npm run analyze

Analyze specific project and generate DOT visualization:

npm run analyze -- -p ../my-nestjs-project -f dot -o dependencies.dot

Generate visualization PNG:

npm run analyze -- -p ../my-nestjs-project -f dot -o ./output/dependencies.dot

The tool will automatically attempt to generate a PNG file if Graphviz is installed.

Output Formats

DOT Format

Generates a DOT file that can be visualized using Graphviz. The output includes:

Module nodes with details (controllers, providers, imports)
Import relationships between modules
Provider dependency relationships

Example:

digraph {
  rankdir=LR;
  node [shape=box, style=filled, fillcolor=lightgray];

  "AppModule" [label="AppModule\nControllers: 1\nProviders: 1\nImports: 16"];
  "AuthModule" [label="AuthModule\nControllers: 1\nProviders: 8\nImports: 3"];
  // ...
}

JSON Format

Provides detailed information about each module including:

Module name and file path
List of imports with their metadata
Providers with dependency information
Controllers count
Export information

Visual Using Graphviz

Example:

Module Analysis

The analyzer examines:

@Module() decorators
Import declarations
Provider dependencies
Controller registrations
Circular dependencies
Injectable services
Module exports

Development

Project Structure

nestjs-dependency-analyzer/
├── src/
│   ├── analyzers/
│   │   └── dependency.analyzer.ts
│   ├── parsers/
│   │   └── ast.parser.ts
│   ├── visualizers/
│   │   └── dot.visualizer.ts
│   ├── types/
│   │   └── modules.types.ts
│   |── cli/commands/
│   |    └── analyze.command.ts
|   |── main.ts
├── tests/
└── package.json

Building

npm run build

Contributing

Fork the repository
Create your feature branch (git checkout -b feature/amazing-feature)
Commit your changes (git commit -m 'Add some amazing feature')
Push to the branch (git push origin feature/amazing-feature)
Open a Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments

NestJS team for their amazing framework
Graphviz team for the visualization engine
TypeScript team for the compiler API

Support

For support, please create an issue in the GitHub repository or contact the maintainers.