We use our own python package index at my office, and we're trying to add a new one. When I try to specify both indices at the same time, I get prompted to log in, but if I use only one at a time I don't.

For example:

$ pip install --user --upgrade \
    --extra-index-url https://<api token>:@packagecloud.io/2rs2ts/oldrepo/pypi/simple \
    --extra-index-url https://<other api token>:@packagecloud.io/2rs2ts/newrepo/pypi/simple \
    mypackage
Collecting mypackage
User for packagecloud.io:

But if I specify just one of either of those --extra-index-url arguments then I download my package just fine.

I'm 99% certain that I am passing the arguments correctly, since it's specified with an append action in the source. So I think the problem is that both of these index URLs are from packagecloud.io... but I could be wrong. Either way, how can I use both of my repos?

Apparently this is a bug in pip. The HTTP basic auth information is not stored correctly when specifying multiple --extra-index-urls that point to the same domain. I filed an issue, but in the meantime, there is a workaround. By specifying one of the --extra-index-urls as the --index instead, and adding PyPI as an --extra-index-url, I was able to download my package successfully:

$ pip install --user --upgrade \
    --index https://<api token>:@packagecloud.io/2rs2ts/oldrepo/pypi/simple \
    --extra-index-url https://<other api token>:@packagecloud.io/2rs2ts/newrepo/pypi/simple \
    --extra-index-url https://pypi.python.org/simple \
    mypackage
Collecting mypackage
  Downloading https://packagecloud.io/2rs2ts/newrepo/pypi/packages/mypackage-1.0.0-py2-none-any.whl (52kB)
etc. etc.