Comment 23 for bug 1242942

Reviewed: https://review.openstack.org/67097
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=4228c0ebc237d821a8784a1dcf165f238cddc56e
Submitter: Jenkins
Branch: stable/havana

commit 4228c0ebc237d821a8784a1dcf165f238cddc56e
Author: Flavio Percoco <email address hidden>
Date: Tue Dec 10 12:31:50 2013 +0100

    Move driver initialization check into the method

    Volumes and backups managers' methods are decorated with
    `require_initialized_driver` which checks whether the driver has been
    initialized or not. The decorator fails with a `DriverNotInitialized`
    exception if the driver hasn't been initialized.

    This early failure leaves volumes and backups in a wrong status which is
    not just confusing for the user but it also makes it difficult to do
    anything with the resources after they've been left in a 'bogus' status.

    For example, when a volume creation is requested, the volume is first
    created in the database and its status is set to 'creating'. Then the
    scheduler will pick an available volume node and send the task to it. If
    the driver has not been initialized, the volume status will be left as
    'creating' instead of 'error'.

    This patch fixes that issue by moving the driver initialization check
    into the various manager's methods. In some cases this check is done at
    the very beginning of the method, in some others - either to avoid code
    duplication or because the lines above the check made sense to be
    executed first - this check is done later in the method.

    NOTE: Regardless the conflicts noted below, this patch should be
    backported. The issue it fixes is a source of several bug reports, user
    frustration and confusion. The conflicts were related to some additions
    in the master branch. Resolving the conflicts was pretty
    straightforward.

    Conflicts:
     cinder/tests/test_volume.py
     cinder/utils.py
     cinder/volume/flows/create_volume/__init__.py
     cinder/volume/manager.py

    Closes-bug: #1242942
    (cherry picked from commit 5be4620ae5bb50c8436de0e11269c85a095ed40b)
    Change-Id: I2610be6ba1aa7df417f1a1f7bb27af30273e4814