The dependency cache is timing out

[ciarancourtney]

From #11

Installing a package which has an alias, like pyvbox/virtualbox, fails with:

Problem getting dependency data: DependencyError { details: "Network error" }

[ciarancourtney]

Twisted is another example, I remember having issues installing it with pip years ago around v18 maybe

[David-OConnor]

I can reproduce this one.

[David-OConnor]

You actually identified the problem as well: The bug is in the pydeps repo. This repo downloads packages to find their dependencies, then caches them. If a wheel's avail, it downloads directly. If not, it installs using Pip-9, from the Heroku buildpack.

This bug occurs due to a combination of those packages having no Python3 wheels, and using a different package name from the folder it installs to. I need to figure out how to either update Pip on Heroku, parse the source dists' deps directly, or switch to a different host.

[ciarancourtney]

Does that explain why it seems to work the 2nd time round? https://pastebin.com/raw/j851VMCH

[David-OConnor]

I think I misdiagnosed. I think this is due to a bug in the caching process rather than with Pip or aliases; ie it's failing before giving it a chance to parse the deps when looking at a package for the first time.

[David-OConnor]

Updated the error message to be more clear. I think the solution may be to move hosts for pydeps; Heroku's timing out the request before it finishes downloading/parsing.