cDOT driver deletes a preexisting vserver

[Clinton Knight]

https://github.com/openstack/manila/blob/master/manila/share/drivers/netapp/cluster_mode.py#L441

In the vserver (i.e. share server) creation method, a vserver is created if it doesn't exist, otherwise the vserver setup logic continues in the same method. But if any LIF creation fails, the vserver is deleted *even if it already existed*. This is clearly a bug as coded.

In reality, the driver should not be asked to create a vserver that already exists, that is an error condition. Ben asked for a change in behavior to raise an exception if a vserver already exists when the driver is asked to create it. That was done during the cDOT driver refactoring project and resolved this bug.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/153622

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/153622
Committed: https://git.openstack.org/cgit/openstack/manila/commit/?id=12eeedb6392462c8aa2a0afa5763e0a4612cc475
Submitter: Jenkins
Branch: master

commit 12eeedb6392462c8aa2a0afa5763e0a4612cc475
Author: Clinton Knight <email address hidden>
Date: Thu Jan 8 18:01:08 2015 -0500

    Manila NetApp cDOT driver refactoring

    The Manila cDOT driver is a single file exceeding 1200 lines. It contains
    multiple things (driver code, protocol helpers, ZAPI invocation code,
    options) that should be split apart to allow for easier maintenance and
    readability and add the potential for code sharing when we reintroduce
    a 7-mode driver, add a single-SVM cDOT driver, etc.

    We recently refactored NetApp's DOT Cinder drivers into a 4-layer
    structure (interface, library, client, API) that separates concerns and
    achieves the goals set forth above. This commit satisfies a plan to
    do the same thing in Manila. The implementation steps are:

    1. Update directory structure to match that of the Cinder NetApp drivers
    2. Create driver interface shim
    3. Move driver code to library (with base & C-mode classes, to allow for
       7-mode code sharing later)
    4. Move protocol helpers to separate files (already organized by base &
       C-mode classes)
    5. Split out ZAPI code to client layer (with base & C-mode classes, to
       allow for 7-mode code sharing later)
    6. Implement NetApp driver factory as in Cinder
    7. Implement common NetApp options file as in Cinder
    8. Implement cDOT API call optimizations
    9. Update all unit tests as needed

    Note that this patch appears to treble the total number of code lines.
    This is due to the addition of many more unit tests plus a large amount
    of fake controller API data to feed the API client tests.

    Implements: blueprint netapp-manila-cdot-driver-refactoring
    Closes-Bug: #1410317
    Partial-Bug: #1396953
    Closes-Bug: #1370965
    Closes-Bug: #1418690
    Closes-Bug: #1418696

    Change-Id: I3fc0d09adf84a3708f110a89a7c8c760f4ce3588