Synnefo » snf-ganeti

class LUSetGroupParams(LogicalUnit):

  """Modifies the parameters of a node group.

  """

  HPATH = None

  HTYPE = None

  _OP_PARAMS = [

    _PGroupName,

    ("ndparams", None, ht.TOr(ht.TDict, ht.TNone)),

    ]

  REQ_BGL = False

  def CheckArguments(self):

    all_changes = [

      self.op.ndparams,

      ]

    if all_changes.count(None) == len(all_changes):

      raise errors.OpPrereqError("Please pass at least one modification",

                                 errors.ECODE_INVAL)

  def ExpandNames(self):

    # This raises errors.OpPrereqError on its own:

    self.group_uuid = self.cfg.LookupNodeGroup(self.op.group_name)

    self.needed_locks = {

      locking.LEVEL_NODEGROUP: [self.group_uuid],

      }

  def CheckPrereq(self):

    """Check prerequisites.

    """

    self.group = self.cfg.GetNodeGroup(self.group_uuid)

    if self.group is None:

      raise errors.OpExecError("Could not retrieve group '%s' (UUID: %s)" %

                               (self.op.group_name, self.group_uuid))

    if self.op.ndparams:

      utils.ForceDictType(self.op.ndparams, constants.NDS_PARAMETER_TYPES)

      self.new_ndparams = self.group.SimpleFillND(self.op.ndparams)

  def Exec(self, feedback_fn):

    """Modifies the node group.

    """

    result = []

    if self.op.ndparams:

      self.group.ndparams = self.new_ndparams

      result.append(("ndparams", str(self.group.ndparams)))

    self.cfg.Update(self.group, feedback_fn)

    return result