Ian Wienand 9e92459592 Document output variables
Several roles are setting facts that are expected to be consumed by
roles following them; generally things like the path to installed
tools, etc.

Add a section to policy about this behaviour in general, noting it
should use the cachable flags to persist the values.

Add specific documentation notes in an "Output Variable" section for
roles currently implementing this behaviour.

Change-Id: I05657fec198176c7d7345e84293f4902c81fa30c
2020-04-17 10:45:15 +02:00
..
2020-04-14 10:20:33 +10:00
2020-04-17 14:50:51 +10:00
2020-04-17 10:45:15 +02:00

Ensure pip is available

This role is intended install the requirements for the pip module on hosts.

Jobs that also wish to call pip via shell commands directly can also use this to ensure pip is available. However, it should be noted that calling pip is ambiguous when supporting many platforms. On some platforms it may install the package under the Python 2 interpreter and in others Python 3. You should use a qualified name (pip2 or pip3) to avoid confusion.

Role Variables

Output Variables

This variable will be set to a command appropriate for general usage with the pip module virtualenv_command argument on the host. On Python 3 hosts this will be the inbuilt venv module, on Python 2 hosts the virtualenv package will be installed (this is avoided on Python 3 hosts as an unnecessary dependency).