confd/client: make it possible to update peer list
[ganeti-local] / lib / opcodes.py
index a5e41de..9fea1a1 100644 (file)
 This module implements the data structures which define the cluster
 operations - the so-called opcodes.
 
-
-This module implements the logic for doing operations in the cluster. There
-are two kinds of classes defined:
-  - opcodes, which are small classes only holding data for the task at hand
-  - logical units, which know how to deal with their specific opcode only
+Every operation which modifies the cluster state is expressed via
+opcodes.
 
 """
 
@@ -37,16 +34,24 @@ are two kinds of classes defined:
 # pylint: disable-msg=R0903
 
 
-class BaseJO(object):
+class BaseOpCode(object):
   """A simple serializable object.
 
-  This object serves as a parent class for both OpCode and Job since
-  they are serialized in the same way.
+  This object serves as a parent class for OpCode without any custom
+  field handling.
 
   """
   __slots__ = []
 
   def __init__(self, **kwargs):
+    """Constructor for BaseOpCode.
+
+    The constructor takes only keyword arguments and will set
+    attributes on this object based on the passed arguments. As such,
+    it means that you should not pass arguments which are not in the
+    __slots__ attribute for this class.
+
+    """
     for key in kwargs:
       if key not in self.__slots__:
         raise TypeError("Object %s doesn't support the parameter '%s'" %
@@ -54,6 +59,15 @@ class BaseJO(object):
       setattr(self, key, kwargs[key])
 
   def __getstate__(self):
+    """Generic serializer.
+
+    This method just returns the contents of the instance as a
+    dictionary.
+
+    @rtype:  C{dict}
+    @return: the instance attributes and their values
+
+    """
     state = {}
     for name in self.__slots__:
       if hasattr(self, name):
@@ -61,6 +75,15 @@ class BaseJO(object):
     return state
 
   def __setstate__(self, state):
+    """Generic unserializer.
+
+    This method just restores from the serialized state the attributes
+    of the current instance.
+
+    @param state: the serialized opcode data
+    @type state:  C{dict}
+
+    """
     if not isinstance(state, dict):
       raise ValueError("Invalid data to __setstate__: expected dict, got %s" %
                        type(state))
@@ -73,45 +96,33 @@ class BaseJO(object):
       setattr(self, name, state[name])
 
 
-class Job(BaseJO):
-  """Job definition structure"""
-  STATUS_PENDING = 1
-  STATUS_RUNNING = 2
-  STATUS_FINISHED = 3
-  RESULT_OK = 1
-  RESULT_FAIL = 2
-  RESULT_ABORT = 3
-
-  __slots__ = ["job_id", "op_list", "status", "result"]
-
-  def __getstate__(self):
-    """Specialized getstate for jobs
-
-    """
-    data = BaseJO.__getstate__(self)
-    if "op_list" in data:
-      data["op_list"] = [op.__getstate__() for op in data["op_list"]]
-    return data
-
-  def __setstate__(self, state):
-    """Specialized setstate for jobs
+class OpCode(BaseOpCode):
+  """Abstract OpCode.
 
-    """
-    BaseJO.__setstate__(self, state)
-    if "op_list" in state:
-      self.op_list = [OpCode.LoadOpCode(op) for op in state["op_list"]]
+  This is the root of the actual OpCode hierarchy. All clases derived
+  from this class should override OP_ID.
 
+  @cvar OP_ID: The ID of this opcode. This should be unique amongst all
+               children of this class.
+  @ivar dry_run: Whether the LU should be run in dry-run mode, i.e. just
+                 the check steps
 
-class OpCode(BaseJO):
-  """Abstract OpCode"""
+  """
   OP_ID = "OP_ABSTRACT"
-  __slots__ = []
+  __slots__ = BaseOpCode.__slots__ + ["dry_run"]
 
   def __getstate__(self):
     """Specialized getstate for opcodes.
 
+    This method adds to the state dictionary the OP_ID of the class,
+    so that on unload we can identify the correct class for
+    instantiating the opcode.
+
+    @rtype:   C{dict}
+    @return:  the state as a dictionary
+
     """
-    data = BaseJO.__getstate__(self)
+    data = BaseOpCode.__getstate__(self)
     data["OP_ID"] = self.OP_ID
     return data
 
@@ -119,6 +130,13 @@ class OpCode(BaseJO):
   def LoadOpCode(cls, data):
     """Generic load opcode method.
 
+    The method identifies the correct opcode class from the dict-form
+    by looking for a OP_ID key, if this is not found, or its value is
+    not available in this module as a child of this class, we fail.
+
+    @type data:  C{dict}
+    @param data: the serialized opcode
+
     """
     if not isinstance(data, dict):
       raise ValueError("Invalid data to LoadOpCode (%s)" % type(data))
@@ -126,14 +144,9 @@ class OpCode(BaseJO):
       raise ValueError("Invalid data to LoadOpcode, missing OP_ID")
     op_id = data["OP_ID"]
     op_class = None
-    for item in globals().values():
-      if (isinstance(item, type) and
-          issubclass(item, cls) and
-          hasattr(item, "OP_ID") and
-          getattr(item, "OP_ID") == op_id):
-        op_class = item
-        break
-    if op_class is None:
+    if op_id in OP_MAPPING:
+      op_class = OP_MAPPING[op_id]
+    else:
       raise ValueError("Invalid data to LoadOpCode: OP_ID %s unsupported" %
                        op_id)
     op = op_class()
@@ -142,43 +155,62 @@ class OpCode(BaseJO):
     op.__setstate__(new_data)
     return op
 
+  def Summary(self):
+    """Generates a summary description of this opcode.
+
+    """
+    # all OP_ID start with OP_, we remove that
+    txt = self.OP_ID[3:]
+    field_name = getattr(self, "OP_DSC_FIELD", None)
+    if field_name:
+      field_value = getattr(self, field_name, None)
+      txt = "%s(%s)" % (txt, field_value)
+    return txt
+
+
+# cluster opcodes
+
+class OpPostInitCluster(OpCode):
+  """Post cluster initialization.
 
-class OpInitCluster(OpCode):
-  """Initialise the cluster."""
-  OP_ID = "OP_CLUSTER_INIT"
-  __slots__ = ["cluster_name", "secondary_ip", "hypervisor_type",
-               "vg_name", "mac_prefix", "def_bridge", "master_netdev",
-               "file_storage_dir"]
+  This opcode does not touch the cluster at all. Its purpose is to run hooks
+  after the cluster has been initialized.
+
+  """
+  OP_ID = "OP_CLUSTER_POST_INIT"
+  __slots__ = OpCode.__slots__ + []
 
 
 class OpDestroyCluster(OpCode):
-  """Destroy the cluster."""
+  """Destroy the cluster.
+
+  This opcode has no other parameters. All the state is irreversibly
+  lost after the execution of this opcode.
+
+  """
   OP_ID = "OP_CLUSTER_DESTROY"
-  __slots__ = []
+  __slots__ = OpCode.__slots__ + []
 
 
 class OpQueryClusterInfo(OpCode):
   """Query cluster information."""
   OP_ID = "OP_CLUSTER_QUERY"
-  __slots__ = []
-
+  __slots__ = OpCode.__slots__ + []
 
-class OpClusterCopyFile(OpCode):
-  """Copy a file to multiple nodes."""
-  OP_ID = "OP_CLUSTER_COPYFILE"
-  __slots__ = ["nodes", "filename"]
 
+class OpVerifyCluster(OpCode):
+  """Verify the cluster state.
 
-class OpRunClusterCommand(OpCode):
-  """Run a command on multiple nodes."""
-  OP_ID = "OP_CLUSTER_RUNCOMMAND"
-  __slots__ = ["nodes", "command"]
-
+  @type skip_checks: C{list}
+  @ivar skip_checks: steps to be skipped from the verify process; this
+                     needs to be a subset of
+                     L{constants.VERIFY_OPTIONAL_CHECKS}; currently
+                     only L{constants.VERIFY_NPLUSONE_MEM} can be passed
 
-class OpVerifyCluster(OpCode):
-  """Verify the cluster state."""
+  """
   OP_ID = "OP_CLUSTER_VERIFY"
-  __slots__ = []
+  __slots__ = OpCode.__slots__ + ["skip_checks", "verbose", "error_codes",
+                                  "debug_simulate_errors"]
 
 
 class OpVerifyDisks(OpCode):
@@ -186,9 +218,9 @@ class OpVerifyDisks(OpCode):
 
   Parameters: none
 
-  Result: two lists:
+  Result: a tuple of four elements:
     - list of node names with bad data returned (unreachable, etc.)
-    - dist of node names with broken volume groups (values: error msg)
+    - dict of node names with broken volume groups (values: error msg)
     - list of instances with degraded disks (that should be activated)
     - dict of instances with missing logical volumes (values: (node, vol)
       pairs with details about the missing volumes)
@@ -203,57 +235,204 @@ class OpVerifyDisks(OpCode):
 
   """
   OP_ID = "OP_CLUSTER_VERIFY_DISKS"
-  __slots__ = []
+  __slots__ = OpCode.__slots__ + []
 
 
-class OpMasterFailover(OpCode):
-  """Do a master failover."""
-  OP_ID = "OP_CLUSTER_MASTERFAILOVER"
-  __slots__ = []
+class OpRepairDiskSizes(OpCode):
+  """Verify the disk sizes of the instances and fixes configuration
+  mimatches.
 
+  Parameters: optional instances list, in case we want to restrict the
+  checks to only a subset of the instances.
 
-class OpDumpClusterConfig(OpCode):
-  """Dump the cluster configuration."""
-  OP_ID = "OP_CLUSTER_DUMPCONFIG"
-  __slots__ = []
+  Result: a list of tuples, (instance, disk, new-size) for changed
+  configurations.
+
+  In normal operation, the list should be empty.
+
+  @type instances: list
+  @ivar instances: the list of instances to check, or empty for all instances
+
+  """
+  OP_ID = "OP_CLUSTER_REPAIR_DISK_SIZES"
+  __slots__ = ["instances"]
+
+
+class OpQueryConfigValues(OpCode):
+  """Query cluster configuration values."""
+  OP_ID = "OP_CLUSTER_CONFIG_QUERY"
+  __slots__ = OpCode.__slots__ + ["output_fields"]
 
 
 class OpRenameCluster(OpCode):
-  """Rename the cluster."""
+  """Rename the cluster.
+
+  @type name: C{str}
+  @ivar name: The new name of the cluster. The name and/or the master IP
+              address will be changed to match the new name and its IP
+              address.
+
+  """
   OP_ID = "OP_CLUSTER_RENAME"
-  __slots__ = ["name"]
+  OP_DSC_FIELD = "name"
+  __slots__ = OpCode.__slots__ + ["name"]
 
 
 class OpSetClusterParams(OpCode):
-  """Change the parameters of the cluster."""
+  """Change the parameters of the cluster.
+
+  @type vg_name: C{str} or C{None}
+  @ivar vg_name: The new volume group name or None to disable LVM usage.
+
+  """
   OP_ID = "OP_CLUSTER_SET_PARAMS"
-  __slots__ = ["vg_name"]
+  __slots__ = OpCode.__slots__ + [
+    "vg_name",
+    "enabled_hypervisors",
+    "hvparams",
+    "beparams",
+    "nicparams",
+    "candidate_pool_size",
+    ]
 
 
+class OpRedistributeConfig(OpCode):
+  """Force a full push of the cluster configuration.
+
+  """
+  OP_ID = "OP_CLUSTER_REDIST_CONF"
+  __slots__ = OpCode.__slots__ + [
+    ]
+
 # node opcodes
 
 class OpRemoveNode(OpCode):
-  """Remove a node."""
+  """Remove a node.
+
+  @type node_name: C{str}
+  @ivar node_name: The name of the node to remove. If the node still has
+                   instances on it, the operation will fail.
+
+  """
   OP_ID = "OP_NODE_REMOVE"
-  __slots__ = ["node_name"]
+  OP_DSC_FIELD = "node_name"
+  __slots__ = OpCode.__slots__ + ["node_name"]
 
 
 class OpAddNode(OpCode):
-  """Add a node."""
+  """Add a node to the cluster.
+
+  @type node_name: C{str}
+  @ivar node_name: The name of the node to add. This can be a short name,
+                   but it will be expanded to the FQDN.
+  @type primary_ip: IP address
+  @ivar primary_ip: The primary IP of the node. This will be ignored when the
+                    opcode is submitted, but will be filled during the node
+                    add (so it will be visible in the job query).
+  @type secondary_ip: IP address
+  @ivar secondary_ip: The secondary IP of the node. This needs to be passed
+                      if the cluster has been initialized in 'dual-network'
+                      mode, otherwise it must not be given.
+  @type readd: C{bool}
+  @ivar readd: Whether to re-add an existing node to the cluster. If
+               this is not passed, then the operation will abort if the node
+               name is already in the cluster; use this parameter to 'repair'
+               a node that had its configuration broken, or was reinstalled
+               without removal from the cluster.
+
+  """
   OP_ID = "OP_NODE_ADD"
-  __slots__ = ["node_name", "primary_ip", "secondary_ip"]
+  OP_DSC_FIELD = "node_name"
+  __slots__ = OpCode.__slots__ + [
+    "node_name", "primary_ip", "secondary_ip", "readd",
+    ]
 
 
 class OpQueryNodes(OpCode):
   """Compute the list of nodes."""
   OP_ID = "OP_NODE_QUERY"
-  __slots__ = ["output_fields", "names"]
+  __slots__ = OpCode.__slots__ + ["output_fields", "names", "use_locking"]
 
 
 class OpQueryNodeVolumes(OpCode):
   """Get list of volumes on node."""
   OP_ID = "OP_NODE_QUERYVOLS"
-  __slots__ = ["nodes", "output_fields"]
+  __slots__ = OpCode.__slots__ + ["nodes", "output_fields"]
+
+
+class OpQueryNodeStorage(OpCode):
+  """Get information on storage for node(s)."""
+  OP_ID = "OP_NODE_QUERY_STORAGE"
+  __slots__ = OpCode.__slots__ + [
+    "nodes",
+    "storage_type",
+    "name",
+    "output_fields",
+    ]
+
+
+class OpModifyNodeStorage(OpCode):
+  """"""
+  OP_ID = "OP_NODE_MODIFY_STORAGE"
+  __slots__ = OpCode.__slots__ + [
+    "node_name",
+    "storage_type",
+    "name",
+    "changes",
+    ]
+
+
+class OpRepairNodeStorage(OpCode):
+  """Repairs the volume group on a node."""
+  OP_ID = "OP_REPAIR_NODE_STORAGE"
+  OP_DSC_FIELD = "node_name"
+  __slots__ = OpCode.__slots__ + [
+    "node_name",
+    "storage_type",
+    "name",
+    ]
+
+
+class OpSetNodeParams(OpCode):
+  """Change the parameters of a node."""
+  OP_ID = "OP_NODE_SET_PARAMS"
+  OP_DSC_FIELD = "node_name"
+  __slots__ = OpCode.__slots__ + [
+    "node_name",
+    "force",
+    "master_candidate",
+    "offline",
+    "drained",
+    ]
+
+
+class OpPowercycleNode(OpCode):
+  """Tries to powercycle a node."""
+  OP_ID = "OP_NODE_POWERCYCLE"
+  OP_DSC_FIELD = "node_name"
+  __slots__ = OpCode.__slots__ + [
+    "node_name",
+    "force",
+    ]
+
+
+class OpEvacuateNode(OpCode):
+  """Relocate secondary instances from a node."""
+  OP_ID = "OP_NODE_EVACUATE"
+  OP_DSC_FIELD = "node_name"
+  __slots__ = OpCode.__slots__ + [
+    "node_name", "remote_node", "iallocator",
+    ]
+
+
+class OpMigrateNode(OpCode):
+  """Migrate all instances from a node."""
+  OP_ID = "OP_NODE_MIGRATE"
+  OP_DSC_FIELD = "node_name"
+  __slots__ = OpCode.__slots__ + [
+    "node_name",
+    "live",
+    ]
 
 
 # instance opcodes
@@ -261,101 +440,169 @@ class OpQueryNodeVolumes(OpCode):
 class OpCreateInstance(OpCode):
   """Create an instance."""
   OP_ID = "OP_INSTANCE_CREATE"
-  __slots__ = [
-    "instance_name", "mem_size", "disk_size", "os_type", "pnode",
-    "disk_template", "snode", "swap_size", "mode",
-    "vcpus", "ip", "bridge", "src_node", "src_path", "start",
-    "wait_for_sync", "ip_check", "mac",
-    "kernel_path", "initrd_path", "hvm_boot_order",
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + [
+    "instance_name", "os_type", "pnode",
+    "disk_template", "snode", "mode",
+    "disks", "nics",
+    "src_node", "src_path", "start",
+    "wait_for_sync", "ip_check",
     "file_storage_dir", "file_driver",
+    "iallocator",
+    "hypervisor", "hvparams", "beparams",
+    "dry_run",
     ]
 
 
 class OpReinstallInstance(OpCode):
   """Reinstall an instance's OS."""
   OP_ID = "OP_INSTANCE_REINSTALL"
-  __slots__ = ["instance_name", "os_type"]
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + ["instance_name", "os_type"]
 
 
 class OpRemoveInstance(OpCode):
   """Remove an instance."""
   OP_ID = "OP_INSTANCE_REMOVE"
-  __slots__ = ["instance_name", "ignore_failures"]
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + ["instance_name", "ignore_failures"]
 
 
 class OpRenameInstance(OpCode):
   """Rename an instance."""
   OP_ID = "OP_INSTANCE_RENAME"
-  __slots__ = ["instance_name", "ignore_ip", "new_name"]
+  __slots__ = OpCode.__slots__ + [
+    "instance_name", "ignore_ip", "new_name",
+    ]
 
 
 class OpStartupInstance(OpCode):
   """Startup an instance."""
   OP_ID = "OP_INSTANCE_STARTUP"
-  __slots__ = ["instance_name", "force", "extra_args"]
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + [
+    "instance_name", "force", "hvparams", "beparams",
+    ]
 
 
 class OpShutdownInstance(OpCode):
   """Shutdown an instance."""
   OP_ID = "OP_INSTANCE_SHUTDOWN"
-  __slots__ = ["instance_name"]
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + ["instance_name"]
 
 
 class OpRebootInstance(OpCode):
   """Reboot an instance."""
   OP_ID = "OP_INSTANCE_REBOOT"
-  __slots__ = ["instance_name", "reboot_type", "extra_args",
-               "ignore_secondaries" ]
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + [
+    "instance_name", "reboot_type", "ignore_secondaries",
+    ]
 
 
 class OpReplaceDisks(OpCode):
   """Replace the disks of an instance."""
   OP_ID = "OP_INSTANCE_REPLACE_DISKS"
-  __slots__ = ["instance_name", "remote_node", "mode", "disks"]
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + [
+    "instance_name", "remote_node", "mode", "disks", "iallocator",
+    ]
 
 
 class OpFailoverInstance(OpCode):
   """Failover an instance."""
   OP_ID = "OP_INSTANCE_FAILOVER"
-  __slots__ = ["instance_name", "ignore_consistency"]
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + ["instance_name", "ignore_consistency"]
+
+
+class OpMigrateInstance(OpCode):
+  """Migrate an instance.
+
+  This migrates (without shutting down an instance) to its secondary
+  node.
+
+  @ivar instance_name: the name of the instance
+
+  """
+  OP_ID = "OP_INSTANCE_MIGRATE"
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + ["instance_name", "live", "cleanup"]
+
+
+class OpMoveInstance(OpCode):
+  """Move an instance.
+
+  This move (with shutting down an instance and data copying) to an
+  arbitrary node.
+
+  @ivar instance_name: the name of the instance
+  @ivar target_node: the destination node
+
+  """
+  OP_ID = "OP_INSTANCE_MOVE"
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + ["instance_name", "target_node"]
 
 
 class OpConnectConsole(OpCode):
   """Connect to an instance's console."""
   OP_ID = "OP_INSTANCE_CONSOLE"
-  __slots__ = ["instance_name"]
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + ["instance_name"]
 
 
 class OpActivateInstanceDisks(OpCode):
   """Activate an instance's disks."""
   OP_ID = "OP_INSTANCE_ACTIVATE_DISKS"
-  __slots__ = ["instance_name"]
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + ["instance_name", "ignore_size"]
 
 
 class OpDeactivateInstanceDisks(OpCode):
   """Deactivate an instance's disks."""
   OP_ID = "OP_INSTANCE_DEACTIVATE_DISKS"
-  __slots__ = ["instance_name"]
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + ["instance_name"]
+
+
+class OpRecreateInstanceDisks(OpCode):
+  """Deactivate an instance's disks."""
+  OP_ID = "OP_INSTANCE_RECREATE_DISKS"
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + ["instance_name", "disks"]
 
 
 class OpQueryInstances(OpCode):
   """Compute the list of instances."""
   OP_ID = "OP_INSTANCE_QUERY"
-  __slots__ = ["output_fields", "names"]
+  __slots__ = OpCode.__slots__ + ["output_fields", "names", "use_locking"]
 
 
 class OpQueryInstanceData(OpCode):
   """Compute the run-time status of instances."""
   OP_ID = "OP_INSTANCE_QUERY_DATA"
-  __slots__ = ["instances"]
+  __slots__ = OpCode.__slots__ + ["instances", "static"]
 
 
 class OpSetInstanceParams(OpCode):
   """Change the parameters of an instance."""
   OP_ID = "OP_INSTANCE_SET_PARAMS"
-  __slots__ = [
-    "instance_name", "mem", "vcpus", "ip", "bridge", "mac",
-    "kernel_path", "initrd_path", "hvm_boot_order",
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + [
+    "instance_name",
+    "hvparams", "beparams", "force",
+    "nics", "disks",
+    ]
+
+
+class OpGrowDisk(OpCode):
+  """Grow a disk of an instance."""
+  OP_ID = "OP_INSTANCE_GROW_DISK"
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + [
+    "instance_name", "disk", "amount", "wait_for_sync",
     ]
 
 
@@ -363,45 +610,55 @@ class OpSetInstanceParams(OpCode):
 class OpDiagnoseOS(OpCode):
   """Compute the list of guest operating systems."""
   OP_ID = "OP_OS_DIAGNOSE"
-  __slots__ = []
+  __slots__ = OpCode.__slots__ + ["output_fields", "names"]
 
 
 # Exports opcodes
 class OpQueryExports(OpCode):
   """Compute the list of exported images."""
   OP_ID = "OP_BACKUP_QUERY"
-  __slots__ = ["nodes"]
+  __slots__ = OpCode.__slots__ + ["nodes", "use_locking"]
 
 
 class OpExportInstance(OpCode):
   """Export an instance."""
   OP_ID = "OP_BACKUP_EXPORT"
-  __slots__ = ["instance_name", "target_node", "shutdown"]
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + ["instance_name", "target_node", "shutdown"]
+
+
+class OpRemoveExport(OpCode):
+  """Remove an instance's export."""
+  OP_ID = "OP_BACKUP_REMOVE"
+  OP_DSC_FIELD = "instance_name"
+  __slots__ = OpCode.__slots__ + ["instance_name"]
 
 
 # Tags opcodes
 class OpGetTags(OpCode):
   """Returns the tags of the given object."""
   OP_ID = "OP_TAGS_GET"
-  __slots__ = ["kind", "name"]
+  OP_DSC_FIELD = "name"
+  __slots__ = OpCode.__slots__ + ["kind", "name"]
 
 
 class OpSearchTags(OpCode):
   """Searches the tags in the cluster for a given pattern."""
   OP_ID = "OP_TAGS_SEARCH"
-  __slots__ = ["pattern"]
+  OP_DSC_FIELD = "pattern"
+  __slots__ = OpCode.__slots__ + ["pattern"]
 
 
 class OpAddTags(OpCode):
   """Add a list of tags on a given object."""
   OP_ID = "OP_TAGS_SET"
-  __slots__ = ["kind", "name", "tags"]
+  __slots__ = OpCode.__slots__ + ["kind", "name", "tags"]
 
 
 class OpDelTags(OpCode):
   """Remove a list of tags from a given object."""
   OP_ID = "OP_TAGS_DEL"
-  __slots__ = ["kind", "name", "tags"]
+  __slots__ = OpCode.__slots__ + ["kind", "name", "tags"]
 
 
 # Test opcodes
@@ -427,4 +684,30 @@ class OpTestDelay(OpCode):
 
   """
   OP_ID = "OP_TEST_DELAY"
-  __slots__ = ["duration", "on_master", "on_nodes"]
+  OP_DSC_FIELD = "duration"
+  __slots__ = OpCode.__slots__ + ["duration", "on_master", "on_nodes"]
+
+
+class OpTestAllocator(OpCode):
+  """Allocator framework testing.
+
+  This opcode has two modes:
+    - gather and return allocator input for a given mode (allocate new
+      or replace secondary) and a given instance definition (direction
+      'in')
+    - run a selected allocator for a given operation (as above) and
+      return the allocator output (direction 'out')
+
+  """
+  OP_ID = "OP_TEST_ALLOCATOR"
+  OP_DSC_FIELD = "allocator"
+  __slots__ = OpCode.__slots__ + [
+    "direction", "mode", "allocator", "name",
+    "mem_size", "disks", "disk_template",
+    "os", "tags", "nics", "vcpus", "hypervisor",
+    ]
+
+
+OP_MAPPING = dict([(v.OP_ID, v) for v in globals().values()
+                   if (isinstance(v, type) and issubclass(v, OpCode) and
+                       hasattr(v, "OP_ID"))])