managing_dependencies.md

Managing dependencies

Managing the dependencies and their versions is crucial for maintaining a stable and reliable application. This guide explains how to update the requirements files using the provided Makefile.

Prerequisites

Before installing/updating the requirements files, make sure you have the following:

• Create A virtual environment

  python -m venv venv
  

• Activate the virtual environment

  source venv/bin/activate
  

• pip-tools installed

  pip install pip-tools
  

pip-tools

pip-tools is a command-line toolset for managing Python package dependencies. It simplifies the management of requirements files, ensuring consistent installations across environments. With pip-tools, you can easily define and synchronize your project's dependencies, maintain reproducibility, and manage isolated virtual environments.

For detailed instructions, refer to the pip-tools documentation.

File Structure

The three requirements files and their corresponding "in" files are located in the app/requirements directory:

• requirements.in: The main requirements
• requirements_dev.in: Requirements specific to development
• requirements_test.in: Requirements specific to testing

Updating the Requirements Files

To update the requirements files, follow these steps:

1. Open a terminal or command prompt and navigate to the root directory
2. Activate your virtual environment

   source venv/bin/activate
   

3. Run the following command to update the requirements files:

   make --directory app requirements
   

   This command uses pip-tools to compile the *.in files into *.txt files with pinned versions and resolves the dependencies
4. After running the command, the updated requirements files will be generated:
   • requirements.txt: Contains the main requirements with pinned versions
   • requirements_dev.txt: Contains development-specific requirements with pinned versions
   • requirements_test.txt: Contains requirements for testing with pinned versions
5. You can now review and modify the generated *.txt files if necessary

Installing the Updated Requirements

To install the updated requirements in your virtual environment, follow these steps:

• Ensure that your virtual environment is still activated. If not run:

  source venv/bin/activate
  

• Run the following command to install the project requirements:

  make --directory app install

  This command will use pip-tools to install the dependencies
• After running the command, the required packages will be installed within your virtual environment.

Conclusion

Updating the requirements files is essential for managing the dependencies effectively. By following the steps outlined in this guide, you can easily update and install the necessary requirements while maintaining a clean and isolated development environment.

Remember to run make requirements whenever you modify the *.in files to ensure that your *.txt files stay up to date with the correct versions of the packages.