Installation from path or url cannot be constrained to a version

[danpawlik]

Environment

• pip version: 19.0.3
• Python version: 3.6
• OS: Ubuntu 18.04

Hi,
Im working for company that is doing own software.
One software require to install keystonemiddleware package. We don't want to install it from pip repository, but using a git.

How to reproduce:

virtualenv -p python3 --no-wheel /opt/openstack/test
/opt/openstack/test/bin/pip install -c "https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt?h=stable/queens" "https://github.com/openstack/keystonemiddleware.git@stable/queens#egg=keystonemiddleware"

It raises an error:

< SOME NOT IMPORTANT/REQUIRED PACKAGES >
Ignoring scandir: markers 'python_version == "2.7"' don't match your environment
Ignoring futures: markers 'python_version == "2.7"' don't match your environment
Ignoring happybase: markers 'python_version == "2.7"' don't match your environment
Ignoring sortedcontainers: markers 'python_version == "3.4"' don't match your environment
Ignoring sortedcontainers: markers 'python_version == "3.5"' don't match your environment
', err: 'Could not satisfy constraints for 'keystonemiddleware': installation from path or url cannot be constrained to a version

Where packages like: scandir, futures, happybase, sortedcontainers are not required for keystonemiddleware.

[pfmoore]

This is expected behaviour. A URL or file requirement references a specific set of source code, and so it makes no sense to supply a version specification as well.

[sdatko]

This bothers me as well. In my case I would like to keep constrains for the remaining dependencies. Wound't it be more appropriate to just skip version checking for that single package specified via URL (but not it's dependencies), possibly with warning instead? Or at least provide an option for ignoring that error.

Moreover, for projects kept in git we often have the possibility to determine version string, when it is set in setup.cfg or determined from versioning git tags (pbr), so it would be technically possible to check them against constraints.

[uranusjr]

Related: #5898. Also see the discussion on distutils-sig (linked mid-thread in the issue).

[pradyunsg]

Also, relevant comment: #5898 (comment)

[danpawlik]

Workaround for that problem:

• git clone my-project
• pip install -c upper-constraints.txt ./my-project

Pip doesn't check the version of local git project. Awesome

[Natim]

Ok you should remove it from the constraint file. But I guess a -e in the constraint file that is the exact same value as the requirements.txt should not complain about it being constrained.