Configuring the App Dockerization

Creating the requirements.txt file

To run without issues, our project depends on other Python packages. These are known as dependencies. Without properly installing these dependencies, our project will not run smoothly or even run at all. So, when moving our project into a Docker container, dependency management is necessary to avoid dependency conflicts and other issues.

Furthermore, each dependency can have various versions. In that case, compatibility issues can arise. A newer version may not be compatible with the older version, resulting in no backward compatibility. Each project needs a specific version of the Python package to run smoothly. Therefore, to handle these dependencies and the particular versions of them required for our application to run smoothly inside the Docker container, we need to create a requirements.txt file and use pip install –r requirements.txt to install it on the RUN command in our Dockerfile.

Conversely, we can install these dependencies directly in the Dockerfile by running multiple RUN commands. However, this is not advisable because running many RUN commands increases the size of the Docker image. This will cause the image to take a longer time to build.

The requirements.txt file is just a list of all the project dependencies and their specific version. Here is the file for our Config app: