"No matching distribution found for dotnetcore2" in pip 20.0.2

Environment

• pip version: 20.0.2
• Python version: 3.6.9
• OS: Ubuntu 18.04 (on docker OS is: Alpine:3.11.3)

Description Pip can seemingly no longer install any version of dotnetcore2. I’m trying to install artifacts-keyring, and has a dependency on dotnetcore2, which I can’t install it.

Expected behavior It should be able to install dotnetcore2.

How to Reproduce pip install dotnetcore2==2.1.11

Output

/app # pip install dotnetcore2==2.1.11
ERROR: Could not find a version that satisfies the requirement dotnetcore2==2.1.11 (from versions: none)
ERROR: No matching distribution found for dotnetcore2==2.1.11

I’ve already downgraded my pip to 19.3.1, and I still got the same error.

[pfmoore]

I don’t know whether it’s relevant here, but the dotnetcore2 PyPI page says “This wheel is not intended for general use. This wheel is published to support Azure Machine Learning SDK.” So it may be worth checking that you are using a supported setup for the Azure ML SDK before spending too much time on this particular issue.

[pradyunsg]

Looks like the output you’ve pasted got truncated somehow.

From taking a look at https://pypi.org/simple/dotnetcore2/, the wheel tags that were generated for you and the fact that you’re on Alpine Linux:

Given that dotnetcore2 does not ship source distributions (there’s no .tag.gz file in the page linked above), pip can only try installing from the wheels available. Alpine Linux uses musl, which makes it incompatible with the manylinux tag (a standard that Python wheels use) which depends on glibc. Your Ubuntu host OS would be compatible with manylinux1, which might have contributed to the confusion. One “easy” fix might be to switch to a glibc-based docker image, to be able to use manylinux1 wheels provided by dotnetcore2.

More details on manylinux1 compatibility can be found in the document describing it: https://www.python.org/dev/peps/pep-0513/#platform-detection-for-installers.