AddVolumeToServerWaitHandler will wait for a volume to be attached to a server.

CreateServerWaitHandler will wait for server creation.

CreateVolumeWaitHandler will wait for volume creation.

DeleteServerWaitHandler will wait for volume deletion.

DeleteVolumeWaitHandler will wait for volume deletion.

ProjectRequestWaitHandler will wait for a request to succeed.

RemoveVolumeFromServerWaitHandler will wait for a volume to be attached to a server.

ResizeServerWaitHandler will wait for server resize It checks for an intermediate resizing status and only then waits for the server to become active.

Interfaces needed for tests.