nova-manage cell_v2 map_cell0 always returns a non-0 exit code

[Matt Riedemann]

See the discussion in this review:

https://review.openstack.org/#/c/409890/1/nova/cmd/manage.py@1289

The map_cell0 CLI is really treated like a function and it's used by the simple_cell_setup command. If map_cell0 is used as a standalone command it always returns a non-0 exit code because it's returning a CellMapping object (or failing with a duplicate entry error if the cell0 mapping already exists).

We should split the main part of the map_cell0 function out into a private method and then treat map_cell0 as a normal CLI with integer exit codes (0 on success, >0 on failure) and print out whatever information is needed when mapping cell0, like the uuid for example.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/420132

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/420132
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=aa7b6ebbb254f00fcb548832941ca9dbd3996d9f
Submitter: Jenkins
Branch: master

commit aa7b6ebbb254f00fcb548832941ca9dbd3996d9f
Author: Dan Peschman <email address hidden>
Date: Fri Jan 13 11:51:51 2017 -0700

    nova-manage cell_v2 map_cell0 exit 0

    This command used to always return 1 because it was returning a data
    structure used by another CLI function. Now it exits 0 if the cell0
    mapping was created succesfully or was already there.

    Closes-Bug: #1656017
    Change-Id: Ie66de8425bb8f65dc9eab9d0da809e94f6d72b1b

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/nova 15.0.0.0b3 development milestone.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/newton
Review: https://review.openstack.org/484801

[OpenStack Infra (hudson-openstack)]

Change abandoned by Thomas Bechtold (<email address hidden>) on branch: stable/newton
Review: https://review.openstack.org/484801
Reason: To late after Pike was released I guess. Sorry..