[question] How to integrate with setup.py?

Using requirements.txt I can do it:

from pip.req import parse_requirements
requirements = [str(r.req) for r in
                parse_requirements('requirements.txt', session=False)]
test_requirements = [str(r.req) for r in
                     parse_requirements('requirements-test.txt', session=False)]

How can I do the same using Pipfile?

[vphilippon]

First, disclaimer: My expertise is mainly with lib packages. I might miss some points. I hold the right to be wrong, and I’m ready to use it! Also, this got me to scratch my head a few time. I’d really like some review on this.

Now, let’s get to this.

I’ll start with this statement @elgertam:

[…] my usage of Pipfile leads me think that install_requires really is almost identical to what goes in the Pipfile. If I need numpy, I pipenv install numpy and a new entry goes into in my Pipfile’s [packages] group […]

You added numpy to your environment, you did not add numpy to the dependencies of your app. Those are two different things. Keep reading, you’ll see what I mean.

In other words, my usage is totally different from requirements.txt, which I used to just generate before committing using pip freeze > requirements.txt.

Surprisingly, your usage is not so different if you think about it:

• Your previous worflow: pip install stuff -> pip freeze > requirements.txt -> feed install_requires from requirements.txt
• Your new (attempted) workflow: pipenv install stuff -> Pipfile automatically updated -> trying to feed install_requires with the Pipfile.
• What’s the intended idea: Add stuff to install_requires -> pipenv install -> Environment and Pipfile.lock are updated.

And for that intended way to work, you want a Pipfile that states that you want to install your app. Something like the requests Pipfile linked by @isobit.

Or, an example:

[[source]]
url = "https://pypi.python.org/simple"
verify_ssl = true

[dev-packages]
pytest = ">=2.8.0"
tox = "*"

[packages]
"-e ." = "*"

Your Pipfile is to describe your environment, not the dependencies of a package. As you see, the Pipfile above defines what I want to install, which is the local package in editable mode.

This may look a bit “useless”, as right now its all drived by a single package, but let say you want to install your app, but with requests[security], but it’s not a strict dependency from your app, you do pipenv install requests[security], and then:

[[source]]
url = "https://pypi.python.org/simple"
verify_ssl = true

[dev-packages]
pytest = ">=2.8.0"
tox = "*"

[packages]
"-e ." = "*"
requests = { extras = ['security'] }

And voilà, here’s an example of the difference between your abstract requirements, and your concrete requirements. Same goes if you wanted to install gunicorn or anything else needed in the environment, but that’s not part of the app itself.

What am I missing here, @vphilippon? Why is Pipfile’s [packages] too constrained to use in install_requires or tests_require?

If I’ve explained this well enough, you can see that its just supposed to be the other way around. You put your dependencies in install_requires, you put you package in the Pipfile, and then you get and environment, with a Pipfile.lock for reproducibility (as it will resolve and respect your package dependencies).

For test_require, I’ll admit I’m not sure that fits in all of this. IIRC, its a setuptools specific feature. We could argue that it’s a set of abstract dependencies for testing, and expect pipenv to resolve and install those then doing pipenv install --dev, for all packages, but I have a feeling that’s not quite right. I dont have a clear idea or opinion on this and the rationale around it, sorry.

I hope this all make sense somehow.

[nateprewitt]

You should be able to accomplish this with the code below. This will load the Pipfile from your current project and return the dependencies in a pip compatible list.

from pipenv.project import Project
from pipenv.utils import convert_deps_to_pip

pfile = Project(chdir=False).parsed_pipfile
requirements = convert_deps_to_pip(pfile['packages'], r=False)
test_requirements = convert_deps_to_pip(pfile['dev-packages'], r=False)

Let us know if you have any further questions 😃