`pip install` to automatically create virtualenv and install from requirements.txt

Don’t know if this was asked somewhere already, but wouldn’t it be nice if doing a simple

pip install

would automatically install from ./requirements.txt and in case the command was refused due to missing sudo privileges (i.e. attempting to install into the system Python site-packages) automatically creates a venv in the current directory (now that we have python -m venv in Python 3) and installs the packages in there. For beginners, this would literally allow installing just the Python 3 interpreter, getting the source code of an application and then installing the dependencies in one command, without having to know any virtualenv stuff in their first encounter with Python.

Having been involved in several beginner Python workshop events as a coach, I think something like this would be a pretty neat feature.

Similar behaviour that is available as npm install for Node apps seems pretty handy to me, when I just fetch some app source and have it ready for launching after issuing a single command.

What do you think?

[msabramo]

It sounds a bit too magical to me and trying to guess what the user intended. Maybe the user didn’t want a virtualenv – or if they did, for what version of Python and what would it be called?

pip install --user and pip install --require-virtualenv might be interesting for this use case.

And it was just discussed that we want to allow sudo pip install – see https://github.com/pypa/pip/pull/2403

[pradyunsg]

This is something that the pipfile format is intended to bring: https://github.com/pypa/pipfile.