Best Practices for Managing Python Application Dependencies

  • Last updated Apr 25, 2024

Python's versatility and rich library ecosystem make it a powerful language for software development. However, effectively managing the dependencies of a Python application is crucial to maintain stability and ensure a hassle-free development process. In this guide, we'll explore best practices for managing Python application dependencies to keep your projects organized, efficient, and up to date.

Application Dependencies Management is the process of managing dependencies of a project which are available in the form of reusable functions in libraries.

To maintain dependencies of a Python project, you must have the following tools installed on your computer:

  • Pip: Pip is a package management utility tool that simplifies installation and management of software packages from Python Package Index (PyPI) and other package indexes. If Pip is not available on your computer then use this guide to install it first.
  • Virtual Environment: Virtual environment is a tool that helps to create an isolated environment for installing dependencies in a Python project. If virtual environment is not available on your computer then use this guide to install it.

To demonstrate managing dependencies in a Python project using pip and virtual environment, I will walk you through the process step by step. Let's assume you have a Python project named "my_project" and want to manage its dependencies:

  1. Open your command prompt or terminal.
  2. Navigate to your project directory:
  3. cd /path/to/my_project
  4. Create a virtual environment:
  5. py -m venv env
    python3 -m venv env

    This will create a virtual environment named "env" in your project directory.

  6. Activate the virtual environment:
  7. .\env\Scripts\activate
    source env/bin/activate

    After activation, your command prompt or terminal should indicate that the virtual environment is active.

  8. Now when your virtual environment is active, you can install and manage dependencies for your project using pip.
  9. To install a dependency, use pip install package-name. For example:
  10. pip install requests

    This will install the "requests" package within your virtual environment.

  11. To view the installed packages in your virtual environment, you can use pip list:
  12. pip list
  13. To freeze the current list of installed dependencies into a requirements.txt file, use pip freeze and save the output to a file:
  14. pip freeze > requirements.txt

    This creates a requirements.txt file containing the project's dependencies and their versions.

  15. When you need to install dependencies listed in a requirements.txt file, you can install them with the following command:
  16. pip install -r requirements.txt
  17. When you're finished working on your project, deactivate the virtual environment using the deactivate command:
  18. deactivate

By following these steps, you've demonstrated how to create a virtual environment, install and manage project dependencies using pip, and maintain a requirements.txt file for easy dependency replication. This approach ensures that your project's dependencies are isolated and can be easily replicated across different environments.