'Removes the encrypted server password from the metadata server
Note that this does not actually change the instance server
password.'

@extensions.expected_errors(404)
@wsgi.response(204)
def clear(self, req, server_id):

    context = req.environ['nova.context']
    context.can(sp_policies.BASE_POLICY_NAME)
    instance = common.get_instance(self.compute_api, context, server_id)
    meta = password.convert_password(context, None)
    instance.system_metadata.update(meta)
    instance.save()
