Comment 5 for bug 1060884

Reviewed: https://review.openstack.org/17565
Committed: http://github.com/openstack/nova/commit/1dc6c806b32044420bf17d3076dd712185b7ac07
Submitter: Jenkins
Branch: master

commit 1dc6c806b32044420bf17d3076dd712185b7ac07
Author: Mark McLoughlin <email address hidden>
Date: Wed Dec 5 23:13:37 2012 +0000

    Fix handling of unimplemented host actions

    Fixes bug #1060884

    Host actions like enable/disable, maintenance mode and power management
    are not implemented in most virt drivers.

    In the case of set_host_enabled() in the libvirt driver, we have a no-op
    implementation. In other cases we have an implementation which raises
    NotImplementedError. Since the default implementation is to do this, we
    should just remove the redundant methods from the drivers which don't
    actually implement these actions. This ensures NotImplementedError is
    consistently raised.

    On the API side, rather than looking at the return value of these
    methods to determine whether they're implemented, we should just catch
    NotImplementedError and return a sensible error message.

    In order to do this, we need to ensure the NotImplementedError is
    properly deserialized from the RemoteError which will encapsualte
    it. The fix for bug #1086798 ensures this happens.

    Finally, add some tests to make sure we properly respond with 501
    when the virt driver doesn't implement these actions.

    Change-Id: I2d4fc51a4b16d5230e61bde75915142ea450557d