Make the number of replicas modifiable when the cluster is running

neoctl gets a new command to change the number of replicas.

The number of replicas becomes a new partition table attribute and
like the PT id, it is stored in the config table. On the other side,
the configuration value for the number of partitions is dropped,
since it can be computed from the partition table, which is
always stored in full.

The -p/-r master options now only apply at database creation.

Some implementation notes:

- The protocol is slightly optimized in that the master now sends
  automatically the whole partition tables to the admin & client
  nodes upon connection, like for storage nodes.
  This makes the protocol more consistent, and the master is the
  only remaining node requesting partition tables, during recovery.

- Some parts become tricky because app.pt can be None in more cases.
  For example, the extra condition in NodeManager.update
  (before app.pt.dropNode) was added for this is the reason.
  Or the 'loadPartitionTable' method (storage) that is not inlined
  because of unit tests.
  Overall, this commit simplifies more than it complicates.

- In the master handlers, we stop hijacking the 'connectionCompleted'
  method for tasks to be performed (often send the full partition
  table) on handler switches.

- The admin's 'bootstrapped' flag could have been removed earlier:
  race conditions can't happen since the AskNodeInformation packet
  was removed (commit d048a52d).

neo/admin/app.py

@@ -21,7 +21,6 @@ from neo.lib.exception import PrimaryFailure
 from .handler import AdminEventHandler, MasterEventHandler, \
     MasterRequestEventHandler
 from neo.lib.bootstrap import BootstrapManager
-from neo.lib.pt import PartitionTable
 from neo.lib.protocol import ClusterStates, Errors, NodeTypes, Packets
 from neo.lib.debug import register as registerLiveDebugger
 
@@ -66,7 +65,6 @@ class Application(BaseApplication):
         super(Application, self).close()
 
     def reset(self):
-        self.bootstrapped = False
         self.master_conn = None
         self.master_node = None
 
@@ -117,39 +115,17 @@ class Application(BaseApplication):
         self.cluster_state = None
         # search, find, connect and identify to the primary master
         bootstrap = BootstrapManager(self, NodeTypes.ADMIN, self.server)
-        self.master_node, self.master_conn, num_partitions, num_replicas = \
-            bootstrap.getPrimaryConnection()
-
-        if self.pt is None:
-            self.pt = PartitionTable(num_partitions, num_replicas)
-        elif self.pt.getPartitions() != num_partitions:
-            # XXX: shouldn't we recover instead of raising ?
-            raise RuntimeError('the number of partitions is inconsistent')
-        elif self.pt.getReplicas() != num_replicas:
-            # XXX: shouldn't we recover instead of raising ?
-            raise RuntimeError('the number of replicas is inconsistent')
+        self.master_node, self.master_conn = bootstrap.getPrimaryConnection()
 
         # passive handler
         self.master_conn.setHandler(self.master_event_handler)
         self.master_conn.ask(Packets.AskClusterState())
-        self.master_conn.ask(Packets.AskPartitionTable())
 
     def sendPartitionTable(self, conn, min_offset, max_offset, uuid):
-        # we have a pt
-        self.pt.log()
-        row_list = []
         if max_offset == 0:
             max_offset = self.pt.getPartitions()
         try:
-            for offset in xrange(min_offset, max_offset):
-                row = []
-                try:
-                    for cell in self.pt.getCellList(offset):
-                        if uuid is None or cell.getUUID() == uuid:
-                            row.append((cell.getUUID(), cell.getState()))
-                except TypeError:
-                    pass
-                row_list.append((offset, row))
+            row_list = map(self.pt.getRow, xrange(min_offset, max_offset))
         except IndexError:
             conn.send(Errors.ProtocolError('invalid partition table offset'))
         else:

neo/admin/handler.py

@@ -17,11 +17,12 @@
 from neo.lib import logging, protocol
 from neo.lib.handler import EventHandler
 from neo.lib.protocol import uuid_str, Packets
+from neo.lib.pt import PartitionTable
 from neo.lib.exception import PrimaryFailure
 
 def check_primary_master(func):
     def wrapper(self, *args, **kw):
-        if self.app.bootstrapped:
+        if self.app.master_conn is not None:
             return func(self, *args, **kw)
         raise protocol.NotReadyError('Not connected to a primary master.')
     return wrapper
@@ -74,6 +75,7 @@ class AdminEventHandler(EventHandler):
     tweakPartitionTable = forward_ask(Packets.TweakPartitionTable)
     setClusterState = forward_ask(Packets.SetClusterState)
     setNodeState = forward_ask(Packets.SetNodeState)
+    setNumReplicas = forward_ask(Packets.SetNumReplicas)
     checkReplicas = forward_ask(Packets.CheckReplicas)
     truncate = forward_ask(Packets.Truncate)
     repair = forward_ask(Packets.Repair)
@@ -112,16 +114,12 @@ class MasterEventHandler(EventHandler):
     def answerClusterState(self, conn, state):
         self.app.cluster_state = state
 
-    def notifyPartitionChanges(self, conn, ptid, cell_list):
-        self.app.pt.update(ptid, cell_list, self.app.nm)
+    def sendPartitionTable(self, conn, ptid, num_replicas, row_list):
+        pt = self.app.pt = object.__new__(PartitionTable)
+        pt.load(ptid, num_replicas, row_list, self.app.nm)
 
-    def answerPartitionTable(self, conn, ptid, row_list):
-        self.app.pt.load(ptid, row_list, self.app.nm)
-        self.app.bootstrapped = True
-
-    def sendPartitionTable(self, conn, ptid, row_list):
-        if self.app.bootstrapped:
-            self.app.pt.load(ptid, row_list, self.app.nm)
+    def notifyPartitionChanges(self, conn, ptid, num_replicas, cell_list):
+        self.app.pt.update(ptid, num_replicas, cell_list, self.app.nm)
 
     def notifyClusterInformation(self, conn, cluster_state):
         self.app.cluster_state = cluster_state

neo/client/app.py

@@ -244,7 +244,6 @@ class Application(ThreadedApplication):
                 # operational. Might raise ConnectionClosed so that the new
                 # primary can be looked-up again.
                 logging.info('Initializing from master')
-                ask(conn, Packets.AskPartitionTable(), handler=handler)
                 ask(conn, Packets.AskLastTransaction(), handler=handler)
                 if self.pt.operational():
                     break

neo/client/handlers/master.py

@@ -26,10 +26,6 @@ from ..exception import NEOStorageError
 class PrimaryBootstrapHandler(AnswerBaseHandler):
     """ Bootstrap handler used when looking for the primary master """
 
-    def answerPartitionTable(self, conn, ptid, row_list):
-        assert row_list
-        self.app.pt.load(ptid, row_list, self.app.nm)
-
     def answerLastTransaction(*args):
         pass
 
@@ -42,9 +38,6 @@ class PrimaryNotificationsHandler(MTEventHandler):
         except PrimaryElected, e:
             self.app.primary_master_node, = e.args
 
-    def _acceptIdentification(self, node, num_partitions, num_replicas):
-        self.app.pt = PartitionTable(num_partitions, num_replicas)
-
     def answerLastTransaction(self, conn, ltid):
         app = self.app
         app_last_tid = app.__dict__.get('last_tid', '')
@@ -134,9 +127,12 @@ class PrimaryNotificationsHandler(MTEventHandler):
         finally:
             app._cache_lock_release()
 
-    def notifyPartitionChanges(self, conn, ptid, cell_list):
-        if self.app.pt.filled():
-            self.app.pt.update(ptid, cell_list, self.app.nm)
+    def sendPartitionTable(self, conn, ptid, num_replicas, row_list):
+        pt = self.app.pt = object.__new__(PartitionTable)
+        pt.load(ptid, num_replicas, row_list, self.app.nm)
+
+    def notifyPartitionChanges(self, conn, ptid, num_replicas, cell_list):
+        self.app.pt.update(ptid, num_replicas, cell_list, self.app.nm)
 
     def notifyNodeInformation(self, conn, timestamp, node_list):
         super(PrimaryNotificationsHandler, self).notifyNodeInformation(

neo/lib/bootstrap.py

@@ -36,8 +36,6 @@ class BootstrapManager(EventHandler):
         self.devpath = devpath
         self.new_nid = new_nid
         self.node_type = node_type
-        self.num_replicas = None
-        self.num_partitions = None
         app.nm.reset()
 
     uuid = property(lambda self: self.app.uuid)
@@ -54,10 +52,8 @@ class BootstrapManager(EventHandler):
     def connectionLost(self, conn, new_state):
         self.current = None
 
-    def _acceptIdentification(self, node, num_partitions, num_replicas):
+    def _acceptIdentification(self, node):
         assert self.current is node, (self.current, node)
-        self.num_partitions = num_partitions
-        self.num_replicas = num_replicas
 
     def getPrimaryConnection(self):
         """
@@ -74,8 +70,7 @@ class BootstrapManager(EventHandler):
             try:
                 while self.current:
                     if self.current.isIdentified():
-                        return (self.current, self.current.getConnection(),
-                            self.num_partitions, self.num_replicas)
+                        return self.current, self.current.getConnection()
                     poll(1)
             except PrimaryElected, e:
                 if self.current:

neo/lib/handler.py

@@ -160,8 +160,7 @@ class EventHandler(object):
     def _acceptIdentification(*args):
         pass
 
-    def acceptIdentification(self, conn, node_type, uuid,
-                             num_partitions, num_replicas, your_uuid):
+    def acceptIdentification(self, conn, node_type, uuid, your_uuid):
         app = self.app
         node = app.nm.getByAddress(conn.getAddress())
         assert node.getConnection() is conn, (node.getConnection(), conn)
@@ -180,7 +179,7 @@ class EventHandler(object):
             elif node.getUUID() != uuid or app.uuid != your_uuid != None:
                 raise ProtocolError('invalid uuids')
             node.setIdentified()
-            self._acceptIdentification(node, num_partitions, num_replicas)
+            self._acceptIdentification(node)
             return
         conn.close()
 

neo/lib/node.py

@@ -486,7 +486,7 @@ class NodeManager(EventQueue):
             # For the first notification, we receive a full list of nodes from
             # the master. Remove all unknown nodes from a previous connection.
             for node in self._node_set.difference(added_list):
-                if app.pt.dropNode(node):
+                if not node.isStorage() or app.pt.dropNode(node):
                     self.remove(node)
         self.log()
         self.executeQueuedEvents()

neo/lib/protocol.py

@@ -616,10 +616,7 @@ PFCellList = PList('cell_list',
 )
 
 PFRowList = PList('row_list',
-    PStruct('row',
-        PNumber('offset'),
-        PFCellList,
-    ),
+    PFCellList,
 )
 
 PFHistoryList = PList('history_list',
@@ -694,8 +691,6 @@ class RequestIdentification(Packet):
     _answer = PStruct('accept_identification',
         PFNodeType,
         PUUID('my_uuid'),
-        PNumber('num_partitions'),
-        PNumber('num_replicas'),
         PUUID('your_uuid'),
     )
 
@@ -751,23 +746,24 @@ class LastIDs(Packet):
 class PartitionTable(Packet):
     """
     Ask storage node the remaining data needed by master to recover.
-    This is also how the clients get the full partition table on connection.
 
-    :nodes: M -> S; C -> M
+    :nodes: M -> S
     """
     _answer = PStruct('answer_partition_table',
         PPTID('ptid'),
+        PNumber('num_replicas'),
         PFRowList,
     )
 
 class NotifyPartitionTable(Packet):
     """
-    Send the full partition table to admin/storage nodes on connection.
+    Send the full partition table to admin/client/storage nodes on connection.
 
-    :nodes: M -> A, S
+    :nodes: M -> A, C, S
     """
     _fmt = PStruct('send_partition_table',
         PPTID('ptid'),
+        PNumber('num_replicas'),
         PFRowList,
     )
 
@@ -779,6 +775,7 @@ class PartitionChanges(Packet):
     """
     _fmt = PStruct('notify_partition_changes',
         PPTID('ptid'),
+        PNumber('num_replicas'),
         PList('cell_list',
             PStruct('cell',
                 PNumber('offset'),
@@ -1271,6 +1268,18 @@ class NotifyNodeInformation(Packet):
         PFNodeList,
     )
 
+class SetNumReplicas(Packet):
+    """
+    Set the number of replicas.
+
+    :nodes: ctl -> A -> M
+    """
+    _fmt = PStruct('set_num_replicas',
+        PNumber('num_replicas'),
+    )
+
+    _answer = Error
+
 class SetClusterState(Packet):
     """
     Set the cluster state.
@@ -1766,6 +1775,8 @@ class Packets(dict):
                     AddPendingNodes, ignore_when_closed=False)
     TweakPartitionTable = register(
                     TweakPartitionTable, ignore_when_closed=False)
+    SetNumReplicas = register(
+                    SetNumReplicas, ignore_when_closed=False)
     SetClusterState = register(
                     SetClusterState, ignore_when_closed=False)
     Repair = register(

neo/lib/pt.py

@@ -86,15 +86,9 @@ class PartitionTable(object):
         'a cell became non-readable whereas all cells were readable'
 
     def __init__(self, num_partitions, num_replicas):
-        self._id = None
         self.np = num_partitions
         self.nr = num_replicas
-        self.num_filled_rows = 0
-        # Note: don't use [[]] * num_partition construct, as it duplicates
-        # instance *references*, so the outer list contains really just one
-        # inner list instance.
-        self.partition_list = [[] for _ in xrange(num_partitions)]
-        self.count_dict = {}
+        self.clear()
 
     def getID(self):
         return self._id
@@ -113,7 +107,7 @@ class PartitionTable(object):
         # instance *references*, so the outer list contains really just one
         # inner list instance.
         self.partition_list = [[] for _ in xrange(self.np)]
-        self.count_dict.clear()
+        self.count_dict = {}
 
     def getAssignedPartitionList(self, uuid):
         """ Return the partition assigned to the specified UUID """
@@ -203,31 +197,31 @@ class PartitionTable(object):
             del self.count_dict[node]
         return not count
 
-    def load(self, ptid, row_list, nm):
+    def _load(self, ptid, num_replicas, row_list, getByUUID):
+        self.__init__(len(row_list), num_replicas)
+        self._id = ptid
+        for offset, row in enumerate(row_list):
+            for uuid, state in row:
+                node = getByUUID(uuid)
+                self._setCell(offset, node, state)
+
+    def load(self, ptid, num_replicas, row_list, nm):
         """
         Load the partition table with the specified PTID, discard all previous
         content.
         """
-        self.clear()
-        self._id = ptid
-        for offset, row in row_list:
-            if offset >= self.getPartitions():
-                raise IndexError
-            for uuid, state in row:
-                node = nm.getByUUID(uuid)
-                # the node must be known by the node manager
-                assert node is not None
-                self._setCell(offset, node, state)
+        self._load(ptid, num_replicas, row_list, nm.getByUUID)
         logging.debug('partition table loaded (ptid=%s)', ptid)
         self.log()
 
-    def update(self, ptid, cell_list, nm):
+    def update(self, ptid, num_replicas, cell_list, nm):
         """
         Update the partition with the cell list supplied. If a node
         is not known, it is created in the node manager and set as unavailable
         """
         assert self._id < ptid, (self._id, ptid)
         self._id = ptid
+        self.nr = num_replicas
         readable_list = []
         for row in self.partition_list:
             if not all(cell.isReadable() for cell in row):
@@ -310,14 +304,11 @@ class PartitionTable(object):
         return True
 
     def getRow(self, offset):
-        row = self.partition_list[offset]
-        if row is None:
-            return []
-        return [(cell.getUUID(), cell.getState()) for cell in row]
+        return [(cell.getUUID(), cell.getState())
+                for cell in self.partition_list[offset]]
 
     def getRowList(self):
-        getRow = self.getRow
-        return [(x, getRow(x)) for x in xrange(self.np)]
+        return map(self.getRow, xrange(self.np))
 
 class MTPartitionTable(PartitionTable):
     """ Thread-safe aware version of the partition table, override only methods

neo/master/app.py

@@ -16,6 +16,7 @@
 
 import sys
 from collections import defaultdict
+from functools import partial
 from time import time
 
 from neo.lib import logging, util
@@ -76,13 +77,11 @@ class Application(BaseApplication):
 
     @classmethod
     def _buildOptionParser(cls):
-        _ = cls.option_parser
-        _.description = "NEO Master node"
+        parser = cls.option_parser
+        parser.description = "NEO Master node"
         cls.addCommonServerOptions('master', '127.0.0.1:10000', '')
 
-        _ = _.group('master')
-        _.int('r', 'replicas', default=0, help="replicas number")
-        _.int('p', 'partitions', default=100, help="partitions number")
+        _ = parser.group('master')
         _.int('A', 'autostart',
             help="minimum number of pending storage nodes to automatically"
                  " start new cluster (to avoid unwanted recreation of the"
@@ -94,6 +93,10 @@ class Application(BaseApplication):
         _.int('i', 'nid',
             help="specify an NID to use for this process (testing purpose)")
 
+        _ = parser.group('database creation')
+        _.int('r', 'replicas', default=0, help="replicas number")
+        _.int('p', 'partitions', default=100, help="partitions number")
+
     def __init__(self, config):
         super(Application, self).__init__(
             config.get('ssl'), config.get('dynamic_master_list'))
@@ -117,14 +120,14 @@ class Application(BaseApplication):
         replicas = config['replicas']
         partitions = config['partitions']
         if replicas < 0:
-            raise RuntimeError, 'replicas must be a positive integer'
+            sys.exit('replicas must be a positive integer')
         if partitions <= 0:
-            raise RuntimeError, 'partitions must be more than zero'
-        self.pt = PartitionTable(partitions, replicas)
+            sys.exit('partitions must be more than zero')
         logging.info('Configuration:')
         logging.info('Partitions: %d', partitions)
         logging.info('Replicas  : %d', replicas)
         logging.info('Name      : %s', self.name)
+        self.newPartitionTable = partial(PartitionTable, partitions, replicas)
 
         self.listening_conn = None
         self.cluster_state = None
@@ -212,17 +215,23 @@ class Application(BaseApplication):
             if node_list:
                 node.send(Packets.NotifyNodeInformation(now, node_list))
 
-    def broadcastPartitionChanges(self, cell_list):
+    def broadcastPartitionChanges(self, cell_list, num_replicas=None):
         """Broadcast a Notify Partition Changes packet."""
-        if cell_list:
-            ptid = self.pt.setNextID()
-            self.pt.logUpdated()
-            packet = Packets.NotifyPartitionChanges(ptid, cell_list)
-            for node in self.nm.getIdentifiedList():
-                # As for broadcastNodesInformation, we don't send the full PT
-                # when pending storage nodes are added, so keep them notified.
-                if not node.isMaster():
-                    node.send(packet)
+        pt = self.pt
+        if num_replicas is not None:
+            pt.setReplicas(num_replicas)
+        elif cell_list:
+            num_replicas = pt.getReplicas()
+        else:
+            return
+        packet = Packets.NotifyPartitionChanges(
+            pt.setNextID(), num_replicas, cell_list)
+        pt.logUpdated()
+        for node in self.nm.getIdentifiedList():
+            # As for broadcastNodesInformation, we don't send the full PT
+            # when pending storage nodes are added, so keep them notified.
+            if not node.isMaster():
+                node.send(packet)
 
     def provideService(self):
         """
@@ -437,16 +446,7 @@ class Application(BaseApplication):
                 conn.send(notification_packet)
             elif conn.isServer():
                 continue
-            if node.isClient():
-                if state == ClusterStates.RUNNING:
-                    handler = self.client_service_handler
-                elif state == ClusterStates.BACKINGUP:
-                    handler = self.client_ro_service_handler
-                else:
-                    if state != ClusterStates.STOPPING:
-                        conn.abort()
-                    continue
-            elif node.isMaster():
+            if node.isMaster():
                 if state == ClusterStates.RECOVERING:
                     handler = self.election_handler
                 else:
@@ -454,10 +454,16 @@ class Application(BaseApplication):
             elif node.isStorage() and storage_handler:
                 handler = storage_handler
             else:
+                # There's a single handler type for admins.
+                # Client can't change handler without being first disconnected.
+                assert state in (
+                    ClusterStates.STOPPING,
+                    ClusterStates.STOPPING_BACKUP,
+                    ) or not node.isClient(), (state, node)
                 continue # keep handler
             if type(handler) is not type(conn.getLastHandler()):
                 conn.setHandler(handler)
-                handler.connectionCompleted(conn, new=False)
+                handler.handlerSwitched(conn, new=False)
         self.cluster_state = state
 
     def getNewUUID(self, uuid, address, node_type):

neo/master/backup_app.py

@@ -111,17 +111,12 @@ class BackupApplication(object):
                     else:
                         break
                     poll(1)
-                node, conn, num_partitions, num_replicas = \
-                    bootstrap.getPrimaryConnection()
+                node, conn = bootstrap.getPrimaryConnection()
                 try:
                     app.changeClusterState(ClusterStates.BACKINGUP)
                     del bootstrap, node
-                    if num_partitions != pt.getPartitions():
-                        raise RuntimeError("inconsistent number of partitions")
                     self.ignore_invalidations = True
-                    self.pt = PartitionTable(num_partitions, num_replicas)
                     conn.setHandler(BackupHandler(self))
-                    conn.ask(Packets.AskPartitionTable())
                     conn.ask(Packets.AskLastTransaction())
                     # debug variable to log how big 'tid_list' can be.
                     self.debug_tid_count = 0

neo/master/handlers/__init__.py

@@ -23,10 +23,6 @@ from neo.lib.protocol import Packets
 class MasterHandler(EventHandler):
     """This class implements a generic part of the event handlers."""
 
-    def connectionCompleted(self, conn, new=None):
-        if new is None:
-            super(MasterHandler, self).connectionCompleted(conn)
-
     def connectionLost(self, conn, new_state=None):
         if self.app.listening_conn: # if running
             self._connectionLost(conn)
@@ -59,17 +55,20 @@ class MasterHandler(EventHandler):
             + app.getNodeInformationDict(node_list)[node.getType()])
         conn.send(Packets.NotifyNodeInformation(monotonic_time(), node_list))
 
-    def askPartitionTable(self, conn):
+    def handlerSwitched(self, conn, new):
         pt = self.app.pt
-        conn.answer(Packets.AnswerPartitionTable(pt.getID(), pt.getRowList()))
+        # Except storages during recovery and secondary masters, all nodes
+        # receives the full partition table as soon as they're identified.
+        # It is also sent in 2 other cases:
+        # - to admins during recovery, whenever a newer PT is loaded;
+        # - to storage when switching from recovery to verification.
+        # After that, non-master nodes only receive incremental updates.
+        conn.send(Packets.SendPartitionTable(
+            pt.getID(), pt.getReplicas(), pt.getRowList()))
 
 
 class BaseServiceHandler(MasterHandler):
-    """This class deals with events for a service phase."""
-
-    def connectionCompleted(self, conn, new):
-        pt = self.app.pt
-        conn.send(Packets.SendPartitionTable(pt.getID(), pt.getRowList()))
+    """Common handler class for storage nodes."""
 
     def connectionLost(self, conn, new_state):
         app = self.app

neo/master/handlers/administration.py

@@ -15,6 +15,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import random
+from functools import wraps
 
 from . import MasterHandler
 from ..app import monotonic_time, StateChangedException
@@ -38,9 +39,25 @@ NODE_STATE_WORKFLOW = {
     NodeTypes.STORAGE: (NodeStates.DOWN, NodeStates.UNKNOWN),
 }
 
+def check_state(*states):
+    def decorator(wrapped):
+        def wrapper(self, *args):
+            state = self.app.getClusterState()
+            if state not in states:
+                raise ProtocolError('%s RPC can not be used in %s state'
+                                    % (wrapped.__name__, state))
+            wrapped(self, *args)
+        return wraps(wrapped)(wrapper)
+    return decorator
+
+
 class AdministrationHandler(MasterHandler):
     """This class deals with messages from the admin node only"""
 
+    def handlerSwitched(self, conn, new):
+        assert new
+        super(AdministrationHandler, self).handlerSwitched(conn, new)
+
     def connectionLost(self, conn, new_state):
         node = self.app.nm.getByUUID(conn.getUUID())
         if node is not None:
@@ -134,16 +151,17 @@ class AdministrationHandler(MasterHandler):
                     monotonic_time(), [node.asTuple()]))
             app.broadcastNodesInformation([node])
 
+    # XXX: Would it be safe to allow more states ?
+    __change_pt_rpc = check_state(
+        ClusterStates.RUNNING,
+        ClusterStates.STARTING_BACKUP,
+        ClusterStates.BACKINGUP)
+
+    @__change_pt_rpc
     def addPendingNodes(self, conn, uuid_list):
         uuids = ', '.join(map(uuid_str, uuid_list))
         logging.debug('Add nodes %s', uuids)
         app = self.app
-        state = app.getClusterState()
-        # XXX: Would it be safe to allow more states ?
-        if state not in (ClusterStates.RUNNING,
-                         ClusterStates.STARTING_BACKUP,
-                         ClusterStates.BACKINGUP):
-            raise ProtocolError('Can not add nodes in %s state' % state)
         # take all pending nodes
         node_list = list(app.pt.addNodeList(node
             for node in app.nm.getStorageList()
@@ -172,24 +190,21 @@ class AdministrationHandler(MasterHandler):
             node.send(repair)
         conn.answer(Errors.Ack(''))
 
+    @__change_pt_rpc
+    def setNumReplicas(self, conn, num_replicas):
+        self.app.broadcastPartitionChanges((), num_replicas)
+        conn.answer(Errors.Ack(''))
+
+    @__change_pt_rpc
     def tweakPartitionTable(self, conn, uuid_list):
         app = self.app
-        state = app.getClusterState()
-        # XXX: Would it be safe to allow more states ?
-        if state not in (ClusterStates.RUNNING,
-                         ClusterStates.STARTING_BACKUP,
-                         ClusterStates.BACKINGUP):
-            raise ProtocolError('Can not tweak partition table in %s state'
-                                % state)
         app.broadcastPartitionChanges(app.pt.tweak([node
             for node in app.nm.getStorageList()
             if node.getUUID() in uuid_list or not node.isRunning()]))
         conn.answer(Errors.Ack(''))
 
+    @check_state(ClusterStates.RUNNING)
     def truncate(self, conn, tid):
-        app = self.app
-        if app.cluster_state != ClusterStates.RUNNING:
-            raise ProtocolError('Can not truncate in this state')
         conn.answer(Errors.Ack(''))
         raise StoppedOperation(tid)
 
@@ -237,3 +252,5 @@ class AdministrationHandler(MasterHandler):
                 node.send(Packets.CheckPartition(
                     offset, source, min_tid, max_tid))
         conn.answer(Errors.Ack(''))
+
+    del __change_pt_rpc

neo/master/handlers/backup.py

@@ -17,6 +17,7 @@
 from neo.lib.exception import PrimaryFailure
 from neo.lib.handler import EventHandler
 from neo.lib.protocol import ZERO_TID
+from neo.lib.pt import PartitionTable
 
 class BackupHandler(EventHandler):
     """Handler dedicated to upstream master during BACKINGUP state"""
@@ -25,12 +26,15 @@ class BackupHandler(EventHandler):
         if self.app.app.listening_conn: # if running
             raise PrimaryFailure('connection lost')
 
-    def answerPartitionTable(self, conn, ptid, row_list):
-        self.app.pt.load(ptid, row_list, self.app.nm)
+    def sendPartitionTable(self, conn, ptid, num_replicas, row_list):
+        app = self.app
+        pt = app.pt = object.__new__(PartitionTable)
+        pt.load(ptid, num_replicas, row_list, self.app.nm)
+        if pt.getPartitions() != app.app.pt.getPartitions():
+            raise RuntimeError("inconsistent number of partitions")
 
-    def notifyPartitionChanges(self, conn, ptid, cell_list):
-        if self.app.pt.filled():
-            self.app.pt.update(ptid, cell_list, self.app.nm)
+    def notifyPartitionChanges(self, conn, ptid, num_replicas, cell_list):
+        self.app.pt.update(ptid, num_replicas, cell_list, self.app.nm)
 
     def answerLastTransaction(self, conn, tid):
         app = self.app

neo/master/handlers/client.py

@@ -22,6 +22,10 @@ from . import MasterHandler
 class ClientServiceHandler(MasterHandler):
     """ Handler dedicated to client during service state """
 
+    def handlerSwitched(self, conn, new):
+        assert new
+        super(ClientServiceHandler, self).handlerSwitched(conn, new)
+
     def _connectionLost(self, conn):
         # cancel its transactions and forgot the node
         app = self.app

neo/master/handlers/identification.py

@@ -128,11 +128,9 @@ class IdentificationHandler(EventHandler):
         conn.answer(Packets.AcceptIdentification(
             NodeTypes.MASTER,
             app.uuid,
-            app.pt.getPartitions(),
-            app.pt.getReplicas(),
             uuid))
         handler._notifyNodeInformation(conn)
-        handler.connectionCompleted(conn, True)
+        handler.handlerSwitched(conn, True)
 
 class SecondaryIdentificationHandler(EventHandler):
 

neo/master/handlers/master.py

@@ -23,6 +23,9 @@ from neo.lib.protocol import ClusterStates, NodeStates, NodeTypes, Packets
 class SecondaryHandler(MasterHandler):
     """Handler used by primary to handle secondary masters"""