Comment 3 for bug 1962771

Reviewed: https://review.opendev.org/c/openstack/nova/+/832164
Committed: https://opendev.org/openstack/nova/commit/56055ede03fff633020e0f34fa4da5c8457a89c6
Submitter: "Zuul (22348)"
Branch: master

commit 56055ede03fff633020e0f34fa4da5c8457a89c6
Author: Fabian Wiesel <email address hidden>
Date: Sat Mar 5 13:53:18 2022 +0000

    VMware: StableMoRefProxy for moref recovery

    The vmwareapi driver uses Managed-Object references throughout the code
    with the assumption that they are stable. It is however a database id,
    which may change during the runtime of the compute node. e.g. If an
    instance is unregistered and re-registerd in the vcenter, the moref will
    change. By wrapping a moref in a proxy object, with an additional method
    to resolve the openstack object to a moref, we can hide those changes
    from a caller.

    MoRef implementation with closure - should ease the transition to stable
    mo-refs One simply has to pass the search function as a closure to the
    MoRef instance, and the very same method will be called when an
    exception is raised for the stored reference.

    Stable Volume refs - The connection_info['data'] contains the
    managed-object reference (moref) as well as the uuid of the volume.
    When the moref become invalid for some reason, we can recover it by
    searching for the volume-uuid as the `config.instanceUuid` attribute
    of the shadow-vm.

    Stable VM Ref - By encapsulating all the parameters for searching for
    the vm-ref again, we can move the retry logic to the session object,
    where we can try to recover the vm-ref should it result in a
    ManagedObjectNotFound exception.

    Use refs as index for fakedb - It was previously using the object-id
    to lookup an object, meaning that you couldn't pass a newly created
    Managed-object-reference like you could over the vmware-api. Now the
    lookup happens over the ref-id string, and in turn some functions
    were refactored to take that into account.

    Partial-Bug: #1962771

    Change-Id: I2a3ddf95b7fe07630855b06e732f8764efb13e91