Managing Python application dependencies

OpenShift gives the Python developer two options to specify their application dependencies. You can specify application dependencies either in the install_requires element in setup.py, in requirements.txt, or both. When dependencies are specified in both the setup.py and requirements.txt files, OpenShift will install all the libraries mentioned in both the files. The setup.py file is required when you want to distribute your library as a package that others can use. All the packages listed on PyPi need to have the setup.py script in their root directory. As you do not want to distribute your web applications as a package, there is no need to use the setup.py file. I recommend that you use requirements.txt for your OpenShift applications. The reason why setup.py exists is that OpenShift initially only supported setup.py and later added support for the requirements.txt file. So to make sure that the existing application continues to work on OpenShift...