envvalidator 1.0.2

EnvValidator is a lightweight Python library that helps validate environment variables against a predefined schema.

EnvValidator

EnvValidator is a lightweight Python library that helps validate environment variables against a predefined schema. It ensures that required variables exist, follow the correct type or format, and falls back to system environment variables when an .env file is missing.

---

Features

• Schema-Based Validation - Define expected environment variables and their types (string, int, bool, regex).
• Automatic Fallback - If no .env file is found, it retrieves values from system environment variables.
• Regex Support - Enforce custom formats (e.g., API keys, UUIDs).
• Error Handling - Provides clear error messages when validation fails.
• Lightweight & Fast - Minimal overhead with a simple API.

---

Requirements

• Python 3.x (recommended: 3.7 or higher)

---

Installation

Install the package using pip:

pip install envvalidator

Usage

Here is an example of how to use EnvValidator:

# Define the expected schema
schema = {
    "DATABASE_URL": "string",
    "DEBUG": "bool",
    "PORT": "int",
    "API_KEY": {"regex": r"^[A-Za-z0-9]{32}$"}  # Ensure 32-character API key format
}

try:
    ENV = envvalidator.validate_env(".env", schema)
    print(ENV)
except ValueError as e:
    print("Configuration error:", e)

Output Example

If .env contains:

DATABASE_URL=postgres://user:pass@localhost:5432/db
DEBUG=true
PORT=8080
API_KEY=1234567890abcdef1234567890abcdef

The output would be:

{
    "DATABASE_URL": "postgres://user:pass@localhost:5432/db",
    "DEBUG": "true",
    "PORT": "8080",
    "API_KEY": "1234567890abcdef1234567890abcdef"
}

If a required variable is missing or does not match the expected type, an error is raised.

How It Works

1. Reads the .env file (if available).
2. Parses key-value pairs and trims whitespace.
3. Checks each variable against the schema:
   • If defined in .env, it is validated.
   • If missing, it looks in system environment variables.
   • If validation fails, an error is raised.
4. Returns a dictionary of validated environment variables.

Limitations

• Does not support deeply nested configurations (e.g., JSON-like structures).
• Assumes all values are stored as strings in environment variables.

Contributing

Contributions are welcome! Feel free to open an issue or submit a pull request if you have suggestions or improvements.

Local Development

To set up a local development environment, follow these steps:

1. Create and activate a virtual environment:

   python -m venv venv
   source venv/bin/activate  # macOS/Linux
   venv\Scripts\activate     # Windows
   pip install -r requirements.txt
   

2. Build & install the project

   python setup.py build
   python setup.py install
   

3. Run an example script to test:

   python examples/example.py
   

The module is now installed in the virtual environment. You can test it by running the example script:

python examples/example.py

License

This project is licensed under the Apache-2.0 License. See the LICENSE file for details.

Author

Developed by Qiyaya

Acknowledgements

Thanks to the Python (and ...) development communities for providing tools and resources to make this project possible.

This styling ensures clarity, proper sectioning, and good readability. Let me know if you`d like any further adjustments!