If DIB_PYTHON_VERSION is < 3 on the !redhat path, that means we're on
an older platform that may not have python3-virtualenv packages. Skip
install.
Ensure the order of operations happens by forcing the installs
Also add a note about limited platform support (patches welcome :)
Change-Id: I18412767f0ebf946d557a0a126285369e96af159
Recent changes in project-config have shown that we leave the system
in an inconsistent state when installing from source. On fedora, we
will have installed the python2 packages, but then used $DIB_PYTHON to
install python3 pip from source!
This tries to clarify the situation. As described in the document,
with package installs, we just install the $DIB_PYTHON packaged
versions.
Source installs want to take over the global namespace. This is the
price you pay for running the latest versions outside package managers
:) The only sane thing seems to be for us to normalise python2 &
python3 versions of pip, setuptools and virtualenv and then hacking
things such that "/usr/bin/pip" and "/usr/bin/virtalenv" remain
defaulted to python2 versions.
Documentation is added
Change-Id: Ibc6572b89e256d1f48b7fe7c672b8b9524dc704f
Currently we install pip/virtualenv with "/usr/local/bin/dib-python".
This means that every time you create a virtualenv, the python
interpreter inside it is called "dib-python" which is confusing.
Add an env var DIB_PYTHON that points directly the to interpreter
available during build, for use when running scripts.
Change-Id: I88ad3c9eb958d58db4631d9b27bc2c592f970345