Env2File - Environment Variable Extractor

env2file is a command-line tool that extracts environment variable keys from .env files and stores them in a separate file. This helps developers easily identify which environment variables an application depends on.

The tool also provides an option to automatically commit the extracted keys to a Git repository.

Features

• Extracts environment variable keys from .env files.
• Stores the keys in a separate file (e.g., .env.example).
• Supports automatic Git integration to commit the extracted keys.
• Built as a native executable using GraalVM for better performance.
• Command-line interface powered by PicoCLI.

Installation

Prerequisites

• Java 17 or later (for running the JAR file).
• GraalVM (if using the compiled binary version).
• Git (if using the Git integration feature).

Download and Install

Option 1: Run with Java

java -jar env2file.jar <path_to_env_file> [output_file]

Option 2: Use the Compiled Binary (GraalVM Native Image)

Make the binary executable and move it to /usr/local/bin for global access:

chmod +x env2file
sudo mv env2file /usr/local/bin/

Now you can run:

env2file <path_to_env_file> [output_file]

Usage

Extract Environment Keys to a File

env2file /path/to/.env .env.example

This will extract all environment variable keys from the .env file and store them in .env.example.

Automatically Commit Extracted Keys to Git

env2file /path/to/repo --git

This will:

1. Extract environment keys from .env files.
2. Store them in .env.example.
3. Commit the changes to the Git repository with the message:

   chore: add environment keys to sample file
   

Automatically Run on git push (Pre-Push Hook)

To automate the execution of env2file every time you run git push, create a Git pre-push hook:

1. Navigate to your Git repository:

   cd /path/to/your/repo

2. Create a new pre-push hook:

   nano .git/hooks/pre-push

3. Add the following script to execute env2file before pushing:

   #!/bin/bash
   env2file --git /path/to/repoo

4. Save the file and give it executable permissions:

   chmod +x .git/hooks/pre-push

Now, every time you run git push, the tool will extract the environment keys, update .env.example, and commit the changes automatically.

Display Help

env2file --help

Example

$ env2file .env .env.example
Wrote 10 environment keys to .env.example

Contributing

Feel free to open issues or submit pull requests if you have improvements or suggestions.