I've come to doubt the wisdom of omitting the metadata or using a
default install location that differs from pip's default location.
Once we download the pip wheel file, we should be able to unpack it to
a secure temporary directory and use it to install itself. That means
we should be able to do a full install of pip by default, rather than
anything that hides the metadata. Updating it later then becomes the
same as updating any other pip installed distribution.

The Linux distros can deal with it by either preinstalling pip as part
of the python packages, or just leave the bootstrap script out of the
Python packages and provide a distinct python-pip package as they do
now. "sudo yum install python-pip" and "sudo apt-get install
python-pip" are already pretty easy ways to bootstrap pip - it's
Windows that really needs the help, and a "it's just like any other
pip maintained package" approach is highly desirable there.

The only trick would be ensuring the pip wheel console script doesn't
collide with the bootstrap script, but worst case, we just special
case that directly in pip.

Cheers,
Nick.

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Nick Coghlan   |   ncoghlan@gmail.com   |   Brisbane, Australia