CloudFormation to Terraform Converter

Table of Contents

1. Introduction
2. Features
3. Prerequisites
4. Installation
5. Usage
   • Web Application
   • Command-Line Interface
6. Project Structure
7. How It Works
8. Customization
9. Limitations
10. Troubleshooting
11. Contributing

Introduction

The CloudFormation to Terraform Converter is a tool that simplifies the process of migrating AWS CloudFormation templates to Terraform configuration files. This tool is designed for cloud engineers and DevOps professionals who are transitioning from AWS-specific infrastructure-as-code to a more cloud-agnostic approach using Terraform.

Features

• Web-based interface for easy file uploads
• Command-line interface for local file conversion
• Supports single file, multiple files, and ZIP file uploads
• Converts CloudFormation (YAML/JSON) to Terraform (.tf) format
• Provides immediate download of converted files
• Allows multiple conversions without page refresh in web interface
• Responsive design for various device sizes

Prerequisites

• Python 3.7+
• Flask
• Werkzeug
• PyYAML
• A modern web browser (Chrome, Firefox, Safari, or Edge) for web interface

Installation

1. Clone the repository:

   git clone https://github.com/aperswal/CloudFormation_To_Terraform.git
   cd CloudFormation_To_Terraform

2. Create a virtual environment (optional but recommended):

   python -m venv venv
   source venv/bin/activate  # On Windows, use `venv\Scripts\activate`

3. Install the required packages:

   pip install -r requirements.txt

Usage

Web Application

1. Start the Flask server:

   python app.py

2. Open a web browser and navigate to http://localhost:5000

3. Click on the "Pick Your Files" button and select your CloudFormation template(s) or a ZIP file containing multiple templates.

4. The conversion will start automatically, and you'll receive a ZIP file with the converted Terraform files.

Command-Line Interface

1. Run the CLI converter:

   python cli_converter.py <input_path> [-o <output_directory>]

   Examples:

   python cli_converter.py my_template.yaml
   python cli_converter.py my_templates_folder
   python cli_converter.py my_templates.zip -o converted_terraform

2. The converted files will be placed in the specified output directory (or converted_files by default).

Project Structure

CloudFormation_To_Terraform/
│
├── app.py                 # Main Flask application
├── cli_converter.py       # Command-line interface for conversion
├── cf_to_tf_converter.py  # Core conversion logic
├── templates/
│   └── index.html         # Main page template
├── static/
│   └── css/
│       └── styles.css     # (Optional) Additional styles
├── requirements.txt       # Python dependencies
└── README.md              # This file

How It Works

1. The user selects CloudFormation files through the web interface or specifies them via command line.
2. Files are processed (either uploaded to the server or read locally).
3. The cf_to_tf_converter.py script processes each file, converting CloudFormation syntax to Terraform.
4. Converted files are either zipped and sent back to the user's browser (web interface) or saved to a local directory (CLI).
5. Temporary files are cleaned up after processing.

Customization

• Modify index.html to change the user interface.
• Adjust styles in static/css/styles.css (if you decide to separate CSS from HTML).
• Extend cf_to_tf_converter.py to support additional CloudFormation resource types or improve conversion accuracy.

Limitations

• Not all CloudFormation resources may have direct Terraform equivalents.
• Complex CloudFormation templates with custom resources or intrinsic functions may require manual adjustment after conversion.
• The tool does not currently support AWS-specific features that don't have Terraform counterparts.

Troubleshooting

• If conversions fail, check the server logs or command-line output for detailed error messages.
• Ensure your CloudFormation templates are valid before attempting conversion.
• For large files or many concurrent users, you may need to adjust Flask's configuration for better performance.

Contributing

Please see contributing.md