ERROR: Could not find a version that satisfies the requirement pywin32==304 (from versions: none)

[dilipvaleti]

When we use this build pack in one of our Heroku instance, we got the below error and build rejected.

I was happened when we add new package called requests-negotiate-sspi
Let me know if this package support need to be added under buildpack.

[zyv]

Hi @dilipvaleti,

This is not a bug in our buildpack. All we do is to export the requirements from Poetry and then run pip on the exported file. The error you are showing comes from pip after our buildpack has already run during the installation step.

Just try this on Ubuntu:

$ poetry export -f requirements.txt -o requirements.txt
$ pip install -r requirements.txt

This will fail in the same way. The README of requests-negotiate-sspi, which you are depending upon says the following:

This package allows for Single-Sign On HTTP Negotiate authentication using the requests library on Windows.

So, this package only works on Windows, and Heroku runs on Ubuntu. You've got no dice...