protocol: switch to msgpack for packet serialization

Not only for performance reasons (at least 3% faster) but also because of
several ugly things in the way packets were defined:
- packet field names, which are only documentary; for roots fields,
  they even just duplicate the packet names
- a lot of repetitions for packet names, and even confusion between the name
  of the packet definition and the name of the actual notify/request packet
- the need to implement field types for anything, like PByte to support new
  compression formats, since PBoolean is not enough

neo/lib/protocol.py is now much smaller.

neo/client/__init__.py

@@ -13,6 +13,13 @@
 ##############################################################################
 
 def patch():
+    # For msgpack & Py2/ZODB5.
+    try:
+        from zodbpickle import binary
+        binary._pack = bytes.__str__
+    except ImportError:
+        pass
+
     from hashlib import md5
     from ZODB.Connection import Connection
 

neo/client/app.py

@@ -181,7 +181,7 @@ class Application(ThreadedApplication):
             with self._connecting_to_master_node:
                 result = self.master_conn
                 if result is None:
-                    self.new_oid_list = ()
+                    self.new_oids = ()
                     result = self.master_conn = self._connectToPrimaryNode()
         return result
 
@@ -305,15 +305,19 @@ class Application(ThreadedApplication):
         """Get a new OID."""
         self._oid_lock_acquire()
         try:
-            if not self.new_oid_list:
+            for oid in self.new_oids:
+                break
+            else:
                 # Get new oid list from master node
                 # we manage a list of oid here to prevent
                 # from asking too many time new oid one by one
                 # from master node
                 self._askPrimary(Packets.AskNewOIDs(100))
-                if not self.new_oid_list:
+                for oid in self.new_oids:
+                    break
+                else:
                     raise NEOStorageError('new_oid failed')
-            self.last_oid = oid = self.new_oid_list.pop()
+            self.last_oid = oid
             return oid
         finally:
             self._oid_lock_release()
@@ -612,7 +616,7 @@ class Application(ThreadedApplication):
         # user and description are cast to str in case they're unicode.
         # BBB: This is not required anymore with recent ZODB.
         packet = Packets.AskStoreTransaction(ttid, str(transaction.user),
-            str(transaction.description), ext, txn_context.cache_dict)
+            str(transaction.description), ext, list(txn_context.cache_dict))
         queue = txn_context.queue
         conn_dict = txn_context.conn_dict
         # Ask in parallel all involved storage nodes to commit object metadata.
@@ -697,7 +701,7 @@ class Application(ThreadedApplication):
         else:
             try:
                 notify(Packets.AbortTransaction(txn_context.ttid,
-                                                txn_context.conn_dict))
+                    list(txn_context.conn_dict)))
             except ConnectionClosed:
                 pass
         # No need to flush queue, as it will be destroyed on return,
@@ -731,7 +735,8 @@ class Application(ThreadedApplication):
         for oid in checked_list:
             del cache_dict[oid]
         ttid = txn_context.ttid
-        p = Packets.AskFinishTransaction(ttid, cache_dict, checked_list)
+        p = Packets.AskFinishTransaction(ttid, list(cache_dict),
+                                         checked_list)
         try:
             tid = self._askPrimary(p, cache_dict=cache_dict, callback=f)
             assert tid

neo/client/handlers/master.py

@@ -163,8 +163,7 @@ class PrimaryAnswersHandler(AnswerBaseHandler):
         self.app.setHandlerData(ttid)
 
     def answerNewOIDs(self, conn, oid_list):
-        oid_list.reverse()
-        self.app.new_oid_list = oid_list
+        self.app.new_oids = iter(oid_list)
 
     def incompleteTransaction(self, conn, message):
         raise NEOStorageError("storage nodes for which vote failed can not be"

neo/client/transactions.py

@@ -26,7 +26,7 @@ from .exception import NEOStorageError
 class _WakeupPacket(object):
 
     handler_method_name = 'pong'
-    decode = tuple
+    _args = ()
     getId = int
 
 class Transaction(object):

neo/lib/connection.py

@@ -16,12 +16,19 @@
 
 from functools import wraps
 from time import time
+import msgpack
+from msgpack.exceptions import UnpackValueError
 
 from . import attributeTracker, logging
 from .connector import ConnectorException, ConnectorDelayedConnection
 from .locking import RLock
-from .protocol import uuid_str, Errors, PacketMalformedError, Packets
-from .util import dummy_read_buffer, ReadBuffer
+from .protocol import uuid_str, Errors, PacketMalformedError, Packets, \
+    Unpacker
+
+@apply
+class dummy_read_buffer(msgpack.Unpacker):
+    def feed(self, _):
+        pass
 
 class ConnectionClosed(Exception):
     pass
@@ -292,7 +299,7 @@ class ListeningConnection(BaseConnection):
             # message.
         else:
             conn._connected()
-            self.em.addWriter(conn) # for ENCODED_VERSION
+            self.em.addWriter(conn) # for HANDSHAKE_PACKET
 
     def getAddress(self):
         return self.connector.getAddress()
@@ -311,12 +318,12 @@ class Connection(BaseConnection):
     client = False
     server = False
     peer_id = None
-    _parser_state = None
+    _total_unpacked = 0
     _timeout = None
 
     def __init__(self, event_manager, *args, **kw):
         BaseConnection.__init__(self, event_manager, *args, **kw)
-        self.read_buf = ReadBuffer()
+        self.read_buf = Unpacker()
         # NOTE cur_id will be set in Server|Client to maintain `cur_id % 2 == const` invariant
         #self.cur_id = 0
         self.aborted = False
@@ -429,42 +436,39 @@ class Connection(BaseConnection):
             self._closure()
 
     def _parse(self):
-        read = self.read_buf.read
-        version = read(4)
-        if version is None:
-            return
-        from .protocol import (ENCODED_VERSION, MAX_PACKET_SIZE,
-                               PACKET_HEADER_FORMAT, Packets)
-        if version != ENCODED_VERSION:
-            logging.warning('Protocol version mismatch with %r', self)
+        from .protocol import HANDSHAKE_PACKET, MAGIC_SIZE, Packets
+        read_buf = self.read_buf
+        handshake = read_buf.read_bytes(len(HANDSHAKE_PACKET))
+        if handshake != HANDSHAKE_PACKET:
+            if HANDSHAKE_PACKET.startswith(handshake): # unlikely so tested last
+                # Not enough data and there's no API to know it in advance.
+                # Put it back.
+                read_buf.feed(handshake)
+                return
+            if HANDSHAKE_PACKET.startswith(handshake[:MAGIC_SIZE]):
+                logging.warning('Protocol version mismatch with %r', self)
+            else:
+                logging.debug('Rejecting non-NEO %r', self)
             raise ConnectorException
-        header_size = PACKET_HEADER_FORMAT.size
-        unpack = PACKET_HEADER_FORMAT.unpack
+        read_next = read_buf.next
+        read_pos = read_buf.tell
         def parse():
-            state = self._parser_state
-            if state is None:
-                header = read(header_size)
-                if header is None:
-                    return
-                msg_id, msg_type, msg_len = unpack(header)
-                try:
-                    packet_klass = Packets[msg_type]
-                except KeyError:
-                    raise PacketMalformedError('Unknown packet type')
-                if msg_len > MAX_PACKET_SIZE:
-                    raise PacketMalformedError('message too big (%d)' % msg_len)
-            else:
-                msg_id, packet_klass, msg_len = state
-            data = read(msg_len)
-            if data is None:
-                # Not enough.
-                if state is None:
-                    self._parser_state = msg_id, packet_klass, msg_len
-            else:
-                self._parser_state = None
-                packet = packet_klass()
-                packet.setContent(msg_id, data)
-                return packet
+            try:
+                msg_id, msg_type, args = read_next()
+            except StopIteration:
+                return
+            except UnpackValueError as e:
+                raise PacketMalformedError(str(e))
+            try:
+                packet_klass = Packets[msg_type]
+            except KeyError:
+                raise PacketMalformedError('Unknown packet type')
+            pos = read_pos()
+            packet = packet_klass(*args)
+            packet.setId(msg_id)
+            packet.size = pos - self._total_unpacked
+            self._total_unpacked = pos
+            return packet
         self._parse = parse
         return parse()
 
@@ -517,7 +521,7 @@ class Connection(BaseConnection):
     def close(self):
         if self.connector is None:
             assert self._on_close is None
-            assert not self.read_buf
+            assert not self.read_buf.read_bytes(1)
             assert not self.isPending()
             return
         # process the network events with the last registered handler to
@@ -528,7 +532,7 @@ class Connection(BaseConnection):
         if self._on_close is not None:
             self._on_close()
             self._on_close = None
-        self.read_buf.clear()
+        self.read_buf = dummy_read_buffer
         try:
             if self.connecting:
                 handler.connectionFailed(self)

neo/lib/connector.py

@@ -19,7 +19,7 @@ import ssl
 import errno
 from time import time
 from . import logging
-from .protocol import ENCODED_VERSION
+from .protocol import HANDSHAKE_PACKET
 
 # Global connector registry.
 # Fill by calling registerConnectorHandler.
@@ -74,15 +74,14 @@ class SocketConnector(object):
         s.setsockopt(socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1)
         # disable Nagle algorithm to reduce latency
         s.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
-        self.queued = [ENCODED_VERSION]
-        self.queue_size = len(ENCODED_VERSION)
+        self.queued = [HANDSHAKE_PACKET]
+        self.queue_size = len(HANDSHAKE_PACKET)
         return self
 
     def queue(self, data):
         was_empty = not self.queued
-        self.queued += data
-        for data in data:
-            self.queue_size += len(data)
+        self.queued.append(data)
+        self.queue_size += len(data)
         return was_empty
 
     def _error(self, op, exc=None):
@@ -172,7 +171,7 @@ class SocketConnector(object):
         except socket.error, e:
             self._error('recv', e)
         if data:
-            read_buf.append(data)
+            read_buf.feed(data)
             return
         self._error('recv')
 
@@ -283,7 +282,7 @@ class _SSL:
                     # non-ragged EOF (peer properly closed its side of connection)
                     self._error('recv', None)
                     return
-                read_buf.append(data)
+                read_buf.feed(data)
         except ssl.SSLWantReadError:
             pass
         except socket.error, e:

neo/lib/dispatcher.py

@@ -23,7 +23,7 @@ NOBODY = []
 class _ConnectionClosed(object):
 
     handler_method_name = 'connectionClosed'
-    decode = tuple
+    _args = ()
 
     class getId(object):
         def __eq__(self, other):

neo/lib/handler.py

@@ -71,7 +71,7 @@ class EventHandler(object):
                 method = getattr(self, packet.handler_method_name)
             except AttributeError:
                 raise UnexpectedPacketError('no handler found')
-            args = packet.decode() or ()
+            args = packet._args
             method(conn, *args, **kw)
         except DelayEvent, e:
             assert not kw, kw
@@ -79,9 +79,6 @@ class EventHandler(object):
         except UnexpectedPacketError, e:
             if not conn.isClosed():
                 self.__unexpectedPacket(conn, packet, *e.args)
-        except PacketMalformedError, e:
-            logging.error('malformed packet from %r: %s', conn, e)
-            conn.close()
         except NotReadyError, message:
             if not conn.isClosed():
                 if not message.args:

neo/lib/logger.py

@@ -154,7 +154,8 @@ class NEOLogger(Logger):
 
     def _setup(self, filename=None, reset=False):
         from . import protocol as p
-        global uuid_str
+        global packb, uuid_str
+        packb =  p.packb
         uuid_str = p.uuid_str
         if self._db is not None:
             self._db.close()
@@ -257,7 +258,7 @@ class NEOLogger(Logger):
                     pktcls.__name__, peer, r.pkt.decode())
             """
             if msg is not None:
-                msg = buffer(msg)
+                msg = buffer(msg if type(msg) is bytes else packb(msg))
             q = "INSERT INTO packet VALUES (?,?,?,?,?,?)"
             x = [r.created, nid, r.msg_id, r.code, peer, msg]
         else:
@@ -307,9 +308,14 @@ class NEOLogger(Logger):
     def packet(self, connection, packet, outgoing):
         #if True or self._db is not None:
         if self._db is not None:
-            body = packet._body
-            if self._max_packet and self._max_packet < len(body):
-                body = None
+            if self._max_packet and self._max_packet < packet.size:
+                args = None
+            else:
+                args = packet._args
+                try:
+                    hash(args)
+                except TypeError:
+                    args = packb(args)
             self._queue(PacketRecord(
                 pkt=packet,
                 created=time(),
@@ -318,7 +324,7 @@ class NEOLogger(Logger):
                 outgoing=outgoing,
                 uuid=connection.getUUID(),
                 addr=connection.getAddress(),
-                msg=body))
+                msg=args))
 
     def node(self, *cluster_nid):
         name = self.name and str(self.name)

neo/lib/protocol.py

@@ -14,27 +14,63 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-import sys
-import traceback
-from cStringIO import StringIO
-from struct import Struct
+import threading
+from functools import partial
+from msgpack import packb
 
 # The protocol version must be increased whenever upgrading a node may require
-# to upgrade other nodes. It is encoded as a 4-bytes big-endian integer and
-# the high order byte 0 is different from TLS Handshake (0x16).
-PROTOCOL_VERSION = 6
-ENCODED_VERSION = Struct('!L').pack(PROTOCOL_VERSION)
+# to upgrade other nodes.
+PROTOCOL_VERSION = 0
+# By encoding the handshake packet with msgpack, the whole NEO stream can be
+# decoded with msgpack. The first byte is 0x92, which is different from TLS
+# Handshake (0x16).
+HANDSHAKE_PACKET = packb(('NEO', PROTOCOL_VERSION))
+# Used to distinguish non-NEO stream from version mismatch.
+MAGIC_SIZE = len(HANDSHAKE_PACKET) - len(packb(PROTOCOL_VERSION))
 
-# Avoid memory errors on corrupted data.
-MAX_PACKET_SIZE = 0x4000000
-
-PACKET_HEADER_FORMAT = Struct('!LHL')
 RESPONSE_MASK = 0x8000
 
+# Avoid some memory errors on corrupted data.
+# Before we use msgpack, we limited the size of a whole packet. That's not
+# possible anymore because the size is not known in advance. Packets bigger
+# than the buffer size are possible (e.g. a huge list of small items) and for
+# that we could compare the stream position (Unpacker.tell); it's not worth it.
+UNPACK_BUFFER_SIZE = 0x4000000
+
+@apply
+def Unpacker():
+    global registerExtType, packb
+    from msgpack import ExtType, unpackb, Packer, Unpacker
+    ext_type_dict = []
+    kw = dict(use_bin_type=True)
+    pack_ext = Packer(**kw).pack
+
+    def registerExtType(getstate, make):
+        code = len(ext_type_dict)
+        ext_type_dict.append(lambda data: make(unpackb(data, use_list=False)))
+        return lambda obj: ExtType(code, pack_ext(getstate(obj)))
+
+    iterable_types = set, tuple
+    def default(obj):
+        try:
+            pack = obj._pack
+        except AttributeError:
+            assert type(obj) in iterable_types, type(obj)
+            return list(obj)
+        return pack()
+    lock = threading.Lock()
+    pack = Packer(default, strict_types=True, **kw).pack
+    def packb(obj):
+        with lock: # in case that 'default' is called
+            return pack(obj)
+
+    return partial(Unpacker, use_list=False, max_buffer_size=UNPACK_BUFFER_SIZE,
+        ext_hook=lambda code, data: ext_type_dict[code](data))
+
 class Enum(tuple):
 
     class Item(int):
-        __slots__ = '_name', '_enum'
+        __slots__ = '_name', '_enum', '_pack'
         def __str__(self):
             return self._name
         def __repr__(self):
@@ -49,31 +85,38 @@ class Enum(tuple):
         names = func.func_code.co_names
         self = tuple.__new__(cls, map(cls.Item, xrange(len(names))))
         self._name = func.__name__
+        pack = registerExtType(int, self.__getitem__)
         for item, name in zip(self, names):
             setattr(self, name, item)
             item._name = name
             item._enum = self
+            item._pack = (lambda x: lambda: x)(pack(item))
         return self
 
     def __repr__(self):
         return "<Enum %s>" % self._name
 
+# The order of extension type is important.
+# Enum types first, sorted alphabetically.
 
 @Enum
-def ErrorCodes():
-    ACK
-    DENIED
-    NOT_READY
-    OID_NOT_FOUND
-    TID_NOT_FOUND
-    OID_DOES_NOT_EXIST
-    PROTOCOL_ERROR
-    REPLICATION_ERROR
-    CHECKING_ERROR
-    BACKEND_NOT_IMPLEMENTED
-    NON_READABLE_CELL
-    READ_ONLY_ACCESS
-    INCOMPLETE_TRANSACTION
+def CellStates():
+    # Write-only cell. Last transactions are missing because storage is/was down
+    # for a while, or because it is new for the partition. It usually becomes
+    # UP_TO_DATE when replication is done.
+    OUT_OF_DATE
+    # Normal state: cell is writable/readable, and it isn't planned to drop it.
+    UP_TO_DATE
+    # Same as UP_TO_DATE, except that it will be discarded as soon as another
+    # node finishes to replicate it. It means a partition is moved from 1 node
+    # to another. It is also discarded immediately if out-of-date.
+    FEEDING
+    # A check revealed that data differs from other replicas. Cell is neither
+    # readable nor writable.
+    CORRUPTED
+    # Not really a state: only used in network packets to tell storages to drop
+    # partitions.
+    DISCARDED
 
 @Enum
 def ClusterStates():
@@ -108,11 +151,20 @@ def ClusterStates():
     STOPPING_BACKUP
 
 @Enum
-def NodeTypes():
-    MASTER
-    STORAGE
-    CLIENT
-    ADMIN
+def ErrorCodes():
+    ACK
+    DENIED
+    NOT_READY
+    OID_NOT_FOUND
+    TID_NOT_FOUND
+    OID_DOES_NOT_EXIST
+    PROTOCOL_ERROR
+    REPLICATION_ERROR
+    CHECKING_ERROR
+    BACKEND_NOT_IMPLEMENTED
+    NON_READABLE_CELL
+    READ_ONLY_ACCESS
+    INCOMPLETE_TRANSACTION
 
 @Enum
 def NodeStates():
@@ -122,23 +174,11 @@ def NodeStates():
     PENDING
 
 @Enum
-def CellStates():
-    # Write-only cell. Last transactions are missing because storage is/was down
-    # for a while, or because it is new for the partition. It usually becomes
-    # UP_TO_DATE when replication is done.
-    OUT_OF_DATE
-    # Normal state: cell is writable/readable, and it isn't planned to drop it.
-    UP_TO_DATE
-    # Same as UP_TO_DATE, except that it will be discarded as soon as another
-    # node finishes to replicate it. It means a partition is moved from 1 node
-    # to another. It is also discarded immediately if out-of-date.
-    FEEDING
-    # A check revealed that data differs from other replicas. Cell is neither
-    # readable nor writable.
-    CORRUPTED
-    # Not really a state: only used in network packets to tell storages to drop
-    # partitions.
-    DISCARDED
+def NodeTypes():
+    MASTER
+    STORAGE
+    CLIENT
+    ADMIN
 
 # used for logging
 node_state_prefix_dict = {
@@ -214,45 +254,24 @@ class NonReadableCell(Exception):
     On such event, the client must retry, preferably another cell.
     """
 
+
 class Packet(object):
     """
-        Base class for any packet definition. The _fmt class attribute must be
-        defined for any non-empty packet.
+        Base class for any packet definition.
     """
     _ignore_when_closed = False
     _request = None
     _answer = None
-    _body = None
     _code = None
-    _fmt = None
     _id = None
+    allow_dict = False
     nodelay = True
     poll_thread = False
 
     def __init__(self, *args):
         assert self._code is not None, "Packet class not registered"
-        if args:
-            buf = StringIO()
-            self._fmt.encode(buf.write, args)
-            self._body = buf.getvalue()
-        else:
-            self._body = ''
-
-    def decode(self):
-        assert self._body is not None
-        if self._fmt is None:
-            return ()
-        buf = StringIO(self._body)
-        try:
-            return self._fmt.decode(buf.read)
-        except ParseError, msg:
-            name = self.__class__.__name__
-            raise PacketMalformedError("%s fail (%s)" % (name, msg))
-
-    def setContent(self, msg_id, body):
-        """ Register the packet content for future decoding """
-        self._id = msg_id
-        self._body = body
+        assert self.allow_dict or dict not in map(type, args), args
+        self._args = args
 
     def setId(self, value):
         self._id = value
@@ -261,14 +280,11 @@ class Packet(object):
         assert self._id is not None, "No identifier applied on the packet"
         return self._id
 
-    def encode(self):
+    def encode(self, packb=packb):
         """ Encode a packet as a string to send it over the network """
-        content = self._body
-        return (PACKET_HEADER_FORMAT.pack(self._id, self._code, len(content)),
-                content)
-
-    def __len__(self):
-        return PACKET_HEADER_FORMAT.size + len(self._body)
+        r = packb((self._id, self._code, self._args))
+        self.size = len(r)
+        return r
 
     def __repr__(self):
         return '%s[%r]' % (self.__class__.__name__, self._id)
@@ -281,10 +297,10 @@ class Packet(object):
         return self._code == other._code
 
     def isError(self):
-        return isinstance(self, Error)
+        return self._code == RESPONSE_MASK
 
     def isResponse(self):
-        return self._code & RESPONSE_MASK == RESPONSE_MASK
+        return self._code & RESPONSE_MASK
 
     def getAnswerClass(self):
         return self._answer
@@ -296,1548 +312,530 @@ class Packet(object):
         """
         return self._ignore_when_closed
 
-class ParseError(Exception):
-    """
-        An exception that encapsulate another and build the 'path' of the
-        packet item that generate the error.
-    """
-    def __init__(self, item, trace):
-        Exception.__init__(self)
-        self._trace = trace
-        self._items = [item]
-
-    def append(self, item):
-        self._items.append(item)
-
-    def __repr__(self):
-        chain = '/'.join([item.getName() for item in reversed(self._items)])
-        return 'at %s:\n%s' % (chain, self._trace)
-
-    __str__ = __repr__
-
-# packet parsers
-
-class PItem(object):
-    """
-        Base class for any packet item, _encode and _decode must be overridden
-        by subclasses.
-    """
-    def __init__(self, name):
-        self._name = name
-
-    def __repr__(self):
-        return self.__class__.__name__
-
-    def getName(self):
-        return self._name
-
-    def _trace(self, method, *args):
-        try:
-            return method(*args)
-        except ParseError, e:
-            # trace and forward exception
-            e.append(self)
-            raise
-        except Exception:
-            # original exception, encapsulate it
-            trace = ''.join(traceback.format_exception(*sys.exc_info())[2:])
-            raise ParseError(self, trace)
-
-    def encode(self, writer, items):
-        return self._trace(self._encode, writer, items)
-
-    def decode(self, reader):
-        return self._trace(self._decode, reader)
-
-    def _encode(self, writer, items):
-        raise NotImplementedError, self.__class__.__name__
-
-    def _decode(self, reader):
-        raise NotImplementedError, self.__class__.__name__
-
-class PStruct(PItem):
-    """
-        Aggregate other items
-    """
-    def __init__(self, name, *items):
-        PItem.__init__(self, name)
-        self._items = items
-
-    def _encode(self, writer, items):
-        assert len(self._items) == len(items), (items, self._items)
-        for item, value in zip(self._items, items):
-            item.encode(writer, value)
-
-    def _decode(self, reader):
-        return tuple([item.decode(reader) for item in self._items])
-
-class PStructItem(PItem):
-    """
-        A single value encoded with struct
-    """
-    def __init__(self, name):
-        PItem.__init__(self, name)
-        struct = Struct(self._fmt)
-        self.pack = struct.pack
-        self.unpack = struct.unpack
-        self.size = struct.size
-
-    def _encode(self, writer, value):
-        writer(self.pack(value))
-
-    def _decode(self, reader):
-        return self.unpack(reader(self.size))[0]
-
-class PStructItemOrNone(PStructItem):
-
-    def _encode(self, writer, value):
-        return writer(self._None if value is None else self.pack(value))
-
-    def _decode(self, reader):
-        value = reader(self.size)
-        return None if value == self._None else self.unpack(value)[0]
-
-class POption(PStruct):
-
-    def _encode(self, writer, value):
-        if value is None:
-            writer('\0')
-        else:
-            writer('\1')
-            PStruct._encode(self, writer, value)
-
-    def _decode(self, reader):
-        if '\0\1'.index(reader(1)):
-            return PStruct._decode(self, reader)
-
-class PList(PStructItem):
-    """
-        A list of homogeneous items
-    """
-    _fmt = '!L'
-
-    def __init__(self, name, item):
-        PStructItem.__init__(self, name)
-        self._item = item
-
-    def _encode(self, writer, items):
-        writer(self.pack(len(items)))
-        item = self._item
-        for value in items:
-            item.encode(writer, value)
-
-    def _decode(self, reader):
-        length = self.unpack(reader(self.size))[0]
-        item = self._item
-        return [item.decode(reader) for _ in xrange(length)]
-
-class PDict(PStructItem):
-    """
-        A dictionary with custom key and value formats
-    """
-    _fmt = '!L'
-
-    def __init__(self, name, key, value):
-        PStructItem.__init__(self, name)
-        self._key = key
-        self._value = value
-
-    def _encode(self, writer, item):
-        assert isinstance(item , dict), (type(item), item)
-        writer(self.pack(len(item)))
-        key, value = self._key, self._value
-        for k, v in item.iteritems():
-            key.encode(writer, k)
-            value.encode(writer, v)
-
-    def _decode(self, reader):
-        length = self.unpack(reader(self.size))[0]
-        key, value = self._key, self._value
-        new_dict = {}
-        for _ in xrange(length):
-            k = key.decode(reader)
-            v = value.decode(reader)
-            new_dict[k] = v
-        return new_dict
-
-class PEnum(PStructItem):
-    """
-        Encapsulate an enumeration value
-    """
-    _fmt = 'b'
 
-    def __init__(self, name, enum):
-        PStructItem.__init__(self, name)
-        self._enum = enum
+class PacketRegistryFactory(dict):
 
-    def _encode(self, writer, item):
-        if item is None:
-            item = -1
-        writer(self.pack(item))
-
-    def _decode(self, reader):
-        code = self.unpack(reader(self.size))[0]
-        if code == -1:
-            return None
-        try:
-            return self._enum[code]
-        except KeyError:
-            enum = self._enum.__class__.__name__
-            raise ValueError, 'Invalid code for %s enum: %r' % (enum, code)
-
-class PString(PStructItem):
-    """
-        A variable-length string
-    """
-    _fmt = '!L'
-
-    def _encode(self, writer, value):
-        writer(self.pack(len(value)))
-        writer(value)
-
-    def _decode(self, reader):
-        length = self.unpack(reader(self.size))[0]
-        return reader(length)
-
-class PAddress(PString):
-    """
-        An host address (IPv4/IPv6)
-    """
-
-    def __init__(self, name):
-        PString.__init__(self, name)
-        self._port = Struct('!H')
-
-    def _encode(self, writer, address):
-        if address:
-            host, port = address
-            PString._encode(self, writer, host)
-            writer(self._port.pack(port))
+    def __call__(self, name, base, d):
+        for k, v in d.items():
+            if isinstance(v, type) and issubclass(v, Packet):
+                v.__name__ = k
+                v.handler_method_name = k[0].lower() + k[1:]
+        # this builds a "singleton"
+        return type('PacketRegistry', base, d)(self)
+
+    def register(self, doc, ignore_when_closed=None, request=False, error=False,
+                       _base=(Packet,), **kw):
+        """ Register a packet in the packet registry """
+        code = len(self)
+        if doc is None:
+            self[code] = None
+            return # None registered only to skip a code number (for compatibility)
+        if error and not request:
+            assert not code
+            code = RESPONSE_MASK
+        kw.update(__doc__=doc, _code=code)
+        packet = type('', _base, kw)
+        # register the request
+        self[code] = packet
+        if request:
+            if ignore_when_closed is None:
+                # By default, on a closed connection:
+                # - request: ignore
+                # - answer: keep
+                # - notification: keep
+                packet._ignore_when_closed = True
+            else:
+                assert ignore_when_closed is False
+            if error:
+                packet._answer = self[RESPONSE_MASK]
+            else:
+                # build a class for the answer
+                code |= RESPONSE_MASK
+                kw['_code'] = code
+                answer = packet._answer = self[code] = type('', _base, kw)
+                return packet, answer
         else:
-            PString._encode(self, writer, '')
+            assert ignore_when_closed is None
+        return packet
 
-    def _decode(self, reader):
-        host = PString._decode(self, reader)
-        if host:
-            p = self._port
-            return host, p.unpack(reader(p.size))[0]
 
-class PBoolean(PStructItem):
-    """
-        A boolean value, encoded as a single byte
-    """
-    _fmt = '!?'
-
-class PNumber(PStructItem):
-    """
-        A integer number (4-bytes length)
-    """
-    _fmt = '!L'
-
-class PIndex(PStructItem):
+class Packets(dict):
     """
-        A big integer to defined indexes in a huge list.
+    Packet registry that checks packet code uniqueness and provides an index
     """
-    _fmt = '!Q'
+    __metaclass__ = PacketRegistryFactory()
+    notify = __metaclass__.register
+    request = partial(notify, request=True)
 
-class PPTID(PStructItemOrNone):
-    """
-        A None value means an invalid PTID
-    """
-    _fmt = '!Q'
-    _None = Struct(_fmt).pack(0)
+    Error = notify("""
+        Error is a special type of message, because this can be sent against
+        any other message, even if such a message does not expect a reply
+        usually.
 
-class PChecksum(PItem):
-    """
-        A hash (SHA1)
-    """
-    def _encode(self, writer, checksum):
-        assert len(checksum) == 20, (len(checksum), checksum)
-        writer(checksum)
+        :nodes: * -> *
+        """, error=True)
 
-    def _decode(self, reader):
-        return reader(20)
+    RequestIdentification, AcceptIdentification = request("""
+        Request a node identification. This must be the first packet for any
+        connection.
 
-class PSignedNull(PStructItemOrNone):
-    _fmt = '!l'
-    _None = Struct(_fmt).pack(0)
+        :nodes: * -> *
+        """, poll_thread=True)
 
-class PUUID(PSignedNull):
-    """
-        An UUID (node identifier, 4-bytes signed integer)
-    """
+    Ping, Pong = request("""
+        Empty request used as network barrier.
 
-class PTID(PItem):
-    """
-        A transaction identifier
-    """
-    def _encode(self, writer, tid):
-        if tid is None:
-            tid = INVALID_TID
-        assert len(tid) == 8, (len(tid), tid)
-        writer(tid)
-
-    def _decode(self, reader):
-        tid = reader(8)
-        if tid == INVALID_TID:
-            tid = None
-        return tid
-
-# same definition, for now
-POID = PTID
-
-class PFloat(PStructItemOrNone):
-    """
-        A float number (8-bytes length)
-    """
-    _fmt = '!d'
-    _None = '\xff' * 8
-
-# common definitions
-
-PFEmpty = PStruct('no_content')
-PFNodeType = PEnum('type', NodeTypes)
-PFNodeState = PEnum('state', NodeStates)
-PFCellState = PEnum('state', CellStates)
-
-PFNodeList = PList('node_list',
-    PStruct('node',
-        PFNodeType,
-        PAddress('address'),
-        PUUID('uuid'),
-        PFNodeState,
-        PFloat('id_timestamp'),
-    ),
-)
-
-PFCellList = PList('cell_list',
-    PStruct('cell',
-        PUUID('uuid'),
-        PFCellState,
-    ),
-)
-
-PFRowList = PList('row_list',
-    PFCellList,
-)
-
-PFHistoryList = PList('history_list',
-    PStruct('history_entry',
-        PTID('serial'),
-        PNumber('size'),
-    ),
-)
-
-PFUUIDList = PList('uuid_list',
-    PUUID('uuid'),
-)
-
-PFTidList = PList('tid_list',
-    PTID('tid'),
-)
-
-PFOidList = PList('oid_list',
-    POID('oid'),
-)
-
-# packets definition
-
-class Error(Packet):
-    """
-    Error is a special type of message, because this can be sent against
-    any other message, even if such a message does not expect a reply
-    usually.
+        :nodes: * -> *
+        """)
 
-    :nodes: * -> *
-    """
-    _fmt = PStruct('error',
-        PNumber('code'),
-        PString('message'),
-    )
+    CloseClient = notify("""
+        Tell peer that it can close the connection if it has finished with us.
 
-class Ping(Packet):
-    """
-    Empty request used as network barrier.
+        :nodes: * -> *
+        """)
 
-    :nodes: * -> *
-    """
-    _answer = PFEmpty
+    AskPrimary, AnswerPrimary = request("""
+        Ask node identier of the current primary master.
 
-class CloseClient(Packet):
-    """
-    Tell peer that it can close the connection if it has finished with us.
+        :nodes: ctl -> A
+        """)
 
-    :nodes: * -> *
-    """
+    NotPrimaryMaster = notify("""
+        Notify peer that I'm not the primary master. Attach any extra
+        information to help the peer joining the cluster.
 
-class RequestIdentification(Packet):
-    """
-    Request a node identification. This must be the first packet for any
-    connection.
+        :nodes: SM -> *
+        """)
 
-    :nodes: * -> *
-    """
-    poll_thread = True
-
-    _fmt = PStruct('request_identification',
-        PFNodeType,
-        PUUID('uuid'),
-        PAddress('address'),
-        PString('name'),
-        PFloat('id_timestamp'),
-        # storage:
-            PList('devpath', PString('devid')),
-            PList('new_nid', PNumber('offset')),
-    )
-
-    _answer = PStruct('accept_identification',
-        PFNodeType,
-        PUUID('my_uuid'),
-        PUUID('your_uuid'),
-    )
-
-class PrimaryMaster(Packet):
-    """
-    Ask node identier of the current primary master.
+    NotifyNodeInformation = notify("""
+        Notify information about one or more nodes.
 
-    :nodes: ctl -> A
-    """
-    _answer = PStruct('answer_primary',
-        PUUID('primary_uuid'),
-    )
+        :nodes: M -> *
+        """)
 
-class NotPrimaryMaster(Packet):
-    """
-    Notify peer that I'm not the primary master. Attach any extra information
-    to help the peer joining the cluster.
+    AskRecovery, AnswerRecovery = request("""
+        Ask storage nodes data needed by master to recover.
+        Reused by `neoctl print ids`.
 
-    :nodes: SM -> *
-    """
-    _fmt = PStruct('not_primary_master',
-        PSignedNull('primary'),
-        PList('known_master_list',
-            PAddress('address'),
-        ),
-    )
-
-class Recovery(Packet):
-    """
-    Ask storage nodes data needed by master to recover.
-    Reused by `neoctl print ids`.
+        :nodes: M -> S; ctl -> A -> M
+        """)
 
-    :nodes: M -> S; ctl -> A -> M
-    """
-    _answer = PStruct('answer_recovery',
-        PPTID('ptid'),
-        PTID('backup_tid'),
-        PTID('truncate_tid'),
-    )
+    AskLastIDs, AnswerLastIDs = request("""
+        Ask the last OID/TID so that a master can initialize its
+        TransactionManager. Reused by `neoctl print ids`.
 
-class LastIDs(Packet):
-    """
-    Ask the last OID/TID so that a master can initialize its TransactionManager.
-    Reused by `neoctl print ids`.
+        :nodes: M -> S; ctl -> A -> M
+        """)
 
-    :nodes: M -> S; ctl -> A -> M
-    """
-    _answer = PStruct('answer_last_ids',
-        POID('last_oid'),
-        PTID('last_tid'),
-    )
+    AskPartitionTable, AnswerPartitionTable = request("""
+        Ask storage node the remaining data needed by master to recover.
 
-class PartitionTable(Packet):
-    """
-    Ask storage node the remaining data needed by master to recover.
+        :nodes: M -> S
+        """)
 
-    :nodes: M -> S
-    """
-    _answer = PStruct('answer_partition_table',
-        PPTID('ptid'),
-        PNumber('num_replicas'),
-        PFRowList,
-    )
+    SendPartitionTable = notify("""
+        Send the full partition table to admin/client/storage nodes on
+        connection.
 
-class NotifyPartitionTable(Packet):
-    """
-    Send the full partition table to admin/client/storage nodes on connection.
+        :nodes: M -> A, C, S
+        """)
 
-    :nodes: M -> A, C, S
-    """
-    _fmt = PStruct('send_partition_table',
-        PPTID('ptid'),
-        PNumber('num_replicas'),
-        PFRowList,
-    )
+    NotifyPartitionChanges = notify("""
+        Notify about changes in the partition table.
 
-class PartitionChanges(Packet):
-    """
-    Notify about changes in the partition table.
+        :nodes: M -> *
+        """)
 
-    :nodes: M -> *
-    """
-    _fmt = PStruct('notify_partition_changes',
-        PPTID('ptid'),
-        PNumber('num_replicas'),
-        PList('cell_list',
-            PStruct('cell',
-                PNumber('offset'),
-                PUUID('uuid'),
-                PFCellState,
-            ),
-        ),
-    )
-
-class StartOperation(Packet):
-    """
-    Tell a storage node to start operation. Before this message, it must only
-    communicate with the primary master.
+    StartOperation = notify("""
+        Tell a storage node to start operation. Before this message,
+        it must only communicate with the primary master.
 
-    :nodes: M -> S
-    """
-    _fmt = PStruct('start_operation',
-        # XXX: Is this boolean needed ? Maybe this
-        #      can be deduced from cluster state.
-        PBoolean('backup'),
-    )
+        :nodes: M -> S
+        """)
 
-class StopOperation(Packet):
-    """
-    Notify that the cluster is not operational anymore. Any operation between
-    nodes must be aborted.
+    StopOperation = notify("""
+        Notify that the cluster is not operational anymore.
+        Any operation between nodes must be aborted.
 
-    :nodes: M -> S, C
-    """
+        :nodes: M -> S, C
+        """)
 
-class UnfinishedTransactions(Packet):
-    """
-    Ask unfinished transactions, which will be replicated when they're finished.
+    AskUnfinishedTransactions, AnswerUnfinishedTransactions = request("""
+        Ask unfinished transactions, which will be replicated
+        when they're finished.
 
-    :nodes: S -> M
-    """
-    _fmt = PStruct('ask_unfinished_transactions',
-        PList('row_list',
-            PNumber('offset'),
-        ),
-    )
-
-    _answer = PStruct('answer_unfinished_transactions',
-        PTID('max_tid'),
-        PList('tid_list',
-            PTID('unfinished_tid'),
-        ),
-    )
-
-class LockedTransactions(Packet):
-    """
-    Ask locked transactions to replay committed transactions that haven't been
-    unlocked.
+        :nodes: S -> M
+        """)
 
-    :nodes: M -> S
-    """
-    _answer = PStruct('answer_locked_transactions',
-        PDict('tid_dict',
-            PTID('ttid'),
-            PTID('tid'),
-        ),
-    )
-
-class FinalTID(Packet):
-    """
-    Return final tid if ttid has been committed, to recover from certain
-    failures during tpc_finish.
+    AskLockedTransactions, AnswerLockedTransactions = request("""
+        Ask locked transactions to replay committed transactions
+        that haven't been unlocked.
 
-    :nodes: M -> S; C -> M, S
-    """
-    _fmt = PStruct('final_tid',
-        PTID('ttid'),
-    )
+        :nodes: M -> S
+        """, allow_dict=True)
 
-    _answer = PStruct('final_tid',
-        PTID('tid'),
-    )
+    AskFinalTID, AnswerFinalTID = request("""
+        Return final tid if ttid has been committed, to recover from certain
+        failures during tpc_finish.
 
-class ValidateTransaction(Packet):
-    """
-    Do replay a committed transaction that was not unlocked.
+        :nodes: M -> S; C -> M, S
+        """)
 
-    :nodes: M -> S
-    """
-    _fmt = PStruct('validate_transaction',
-        PTID('ttid'),
-        PTID('tid'),
-    )
+    ValidateTransaction = notify("""
+        Do replay a committed transaction that was not unlocked.
 
-class BeginTransaction(Packet):
-    """
-    Ask to begin a new transaction. This maps to `tpc_begin`.
+        :nodes: M -> S
+        """)
 
-    :nodes: C -> M
-    """
-    _fmt = PStruct('ask_begin_transaction',
-        PTID('tid'),
-    )
+    AskBeginTransaction, AnswerBeginTransaction = request("""
+        Ask to begin a new transaction. This maps to `tpc_begin`.
 
-    _answer = PStruct('answer_begin_transaction',
-        PTID('tid'),
-    )
+        :nodes: C -> M
+        """)
 
-class FailedVote(Packet):
-    """
-    Report storage nodes for which vote failed.
-    True is returned if it's still possible to finish the transaction.
+    FailedVote = request("""
+        Report storage nodes for which vote failed.
+        True is returned if it's still possible to finish the transaction.
 
-    :nodes: C -> M
-    """
-    _fmt = PStruct('failed_vote',
-        PTID('tid'),
-        PFUUIDList,
-    )
+        :nodes: C -> M
+        """, error=True)
 
-    _answer = Error
+    AskFinishTransaction, AnswerTransactionFinished = request("""
+        Finish a transaction. Return the TID of the committed transaction.
+        This maps to `tpc_finish`.
 
-class FinishTransaction(Packet):
-    """
-    Finish a transaction. Return the TID of the committed transaction.
-    This maps to `tpc_finish`.
+        :nodes: C -> M
+        """, ignore_when_closed=False, poll_thread=True)
 
-    :nodes: C -> M
-    """
-    poll_thread = True
-
-    _fmt = PStruct('ask_finish_transaction',
-        PTID('tid'),
-        PFOidList,
-        PList('checked_list',
-            POID('oid'),
-        ),
-    )
-
-    _answer = PStruct('answer_information_locked',
-        PTID('ttid'),
-        PTID('tid'),
-    )
-
-class NotifyTransactionFinished(Packet):
-    """
-    Notify that a transaction blocking a replication is now finished.
+    AskLockInformation, AnswerInformationLocked = request("""
+        Commit a transaction. The new data is read-locked.
 
-    :nodes: M -> S
-    """
-    _fmt = PStruct('notify_transaction_finished',
-        PTID('ttid'),
-        PTID('max_tid'),
-    )
+        :nodes: M -> S
+        """, ignore_when_closed=False)
 
-class LockInformation(Packet):
-    """
-    Commit a transaction. The new data is read-locked.
+    InvalidateObjects = notify("""
+        Notify about a new transaction modifying objects,
+        invalidating client caches.
 
-    :nodes: M -> S
-    """
-    _fmt = PStruct('ask_lock_informations',
-        PTID('ttid'),
-        PTID('tid'),
-    )
+        :nodes: M -> C
+        """)
 
-    _answer = PStruct('answer_information_locked',
-        PTID('ttid'),
-    )
+    NotifyUnlockInformation = notify("""
+        Notify about a successfully committed transaction. The new data can be
+        unlocked.
 
-class InvalidateObjects(Packet):
-    """
-    Notify about a new transaction modifying objects,
-    invalidating client caches.
+        :nodes: M -> S
+        """)
 
-    :nodes: M -> C
-    """
-    _fmt = PStruct('ask_finish_transaction',
-        PTID('tid'),
-        PFOidList,
-    )
+    AskNewOIDs, AnswerNewOIDs = request("""
+        Ask new OIDs to create objects.
 
-class UnlockInformation(Packet):
-    """
-    Notify about a successfully committed transaction. The new data can be
-    unlocked.
+        :nodes: C -> M
+        """)
 
-    :nodes: M -> S
-    """
-    _fmt = PStruct('notify_unlock_information',
-        PTID('ttid'),
-    )
+    NotifyDeadlock = notify("""
+        Ask master to generate a new TTID that will be used by the client to
+        solve a deadlock by rebasing the transaction on top of concurrent
+        changes.
 
-class GenerateOIDs(Packet):
-    """
-    Ask new OIDs to create objects.
+        :nodes: S -> M -> C
+        """)
 
-    :nodes: C -> M
-    """
-    _fmt = PStruct('ask_new_oids',
-        PNumber('num_oids'),
-    )
+    AskRebaseTransaction, AnswerRebaseTransaction = request("""
+        Rebase a transaction to solve a deadlock.
 
-    _answer = PStruct('answer_new_oids',
-        PFOidList,
-    )
+        :nodes: C -> S
+        """)
 
-class Deadlock(Packet):
-    """
-    Ask master to generate a new TTID that will be used by the client to solve
-    a deadlock by rebasing the transaction on top of concurrent changes.
+    AskRebaseObject, AnswerRebaseObject = request("""
+        Rebase an object change to solve a deadlock.
 
-    :nodes: S -> M -> C
-    """
-    _fmt = PStruct('notify_deadlock',
-        PTID('ttid'),
-        PTID('locking_tid'),
-    )
+        :nodes: C -> S
 
-class RebaseTransaction(Packet):
-    """
-    Rebase a transaction to solve a deadlock.
+        XXX: It is a request packet to simplify the implementation. For more
+             efficiency, this should be turned into a notification, and the
+             RebaseTransaction should answered once all objects are rebased
+             (so that the client can still wait on something).
+        """, data_path=(1, 0, 2, 0))
 
-    :nodes: C -> S
-    """
-    _fmt = PStruct('ask_rebase_transaction',
-        PTID('ttid'),
-        PTID('locking_tid'),
-    )
+    AskStoreObject, AnswerStoreObject = request("""
+        Ask to create/modify an object. This maps to `store`.
 
-    _answer = PStruct('answer_rebase_transaction',
-        PFOidList,
-    )
+        As for IStorage, 'serial' is ZERO_TID for new objects.
 
-class RebaseObject(Packet):
-    """
-    Rebase an object change to solve a deadlock.
+        :nodes: C -> S
+        """, data_path=(0, 2))
 
-    :nodes: C -> S
+    AbortTransaction = notify("""
+        Abort a transaction. This maps to `tpc_abort`.
 
-    XXX: It is a request packet to simplify the implementation. For more
-         efficiency, this should be turned into a notification, and the
-         RebaseTransaction should answered once all objects are rebased
-         (so that the client can still wait on something).
-    """
-    _fmt = PStruct('ask_rebase_object',
-        PTID('ttid'),
-        PTID('oid'),
-    )
-
-    _answer = PStruct('answer_rebase_object',
-        POption('conflict',
-            PTID('serial'),
-            PTID('conflict_serial'),
-            POption('data',
-                PBoolean('compression'),
-                PChecksum('checksum'),
-                PString('data'),
-            ),
-        )
-    )
-
-class StoreObject(Packet):
-    """
-    Ask to create/modify an object. This maps to `store`.
+        :nodes: C -> S; C -> M -> S
+        """)
 
-    As for IStorage, 'serial' is ZERO_TID for new objects.
+    AskStoreTransaction, AnswerStoreTransaction = request("""
+        Ask to store a transaction. Implies vote.
 
-    :nodes: C -> S
-    """
-    _fmt = PStruct('ask_store_object',
-        POID('oid'),
-        PTID('serial'),
-        PBoolean('compression'),
-        PChecksum('checksum'),
-        PString('data'),
-        PTID('data_serial'),
-        PTID('tid'),
-    )
-
-    _answer = PStruct('answer_store_object',
-        PTID('conflict'),
-    )
-
-class AbortTransaction(Packet):
-    """
-    Abort a transaction. This maps to `tpc_abort`.
+        :nodes: C -> S
+        """)
 
-    :nodes: C -> S; C -> M -> S
-    """
-    _fmt = PStruct('abort_transaction',
-        PTID('tid'),
-        PFUUIDList, # unused for * -> S
-    )
+    AskVoteTransaction, AnswerVoteTransaction = request("""
+        Ask to vote a transaction.
 
-class StoreTransaction(Packet):
-    """
-    Ask to store a transaction. Implies vote.
+        :nodes: C -> S
+        """)
 
-    :nodes: C -> S
-    """
-    _fmt = PStruct('ask_store_transaction',
-        PTID('tid'),
-        PString('user'),
-        PString('description'),
-        PString('extension'),
-        PFOidList,
-    )
-    _answer = PFEmpty
-
-class VoteTransaction(Packet):
-    """
-    Ask to vote a transaction.
+    AskObject, AnswerObject = request("""
+        Ask a stored object by its OID, optionally at/before a specific tid.
+        This maps to `load/loadBefore/loadSerial`.
 
-    :nodes: C -> S
-    """
-    _fmt = PStruct('ask_vote_transaction',
-        PTID('tid'),
-    )
-    _answer = PFEmpty
+        :nodes: C -> S
+        """, data_path=(1, 3))
 
-class GetObject(Packet):
-    """
-    Ask a stored object by its OID, optionally at/before a specific tid.
-    This maps to `load/loadBefore/loadSerial`.
+    AskTIDs, AnswerTIDs = request("""
+        Ask for TIDs between a range of offsets. The order of TIDs is
+        descending, and the range is [first, last). This maps to `undoLog`.
 
-    :nodes: C -> S
-    """
-    _fmt = PStruct('ask_object',
-        POID('oid'),
-        PTID('at'),
-        PTID('before'),
-    )
-
-    _answer = PStruct('answer_object',
-        POID('oid'),
-        PTID('serial_start'),
-        PTID('serial_end'),
-        PBoolean('compression'),
-        PChecksum('checksum'),
-        PString('data'),
-        PTID('data_serial'),
-    )
-
-class TIDList(Packet):
-    """
-    Ask for TIDs between a range of offsets. The order of TIDs is descending,
-    and the range is [first, last). This maps to `undoLog`.
+        :nodes: C -> S
+        """)
 
-    :nodes: C -> S
-    """
-    _fmt = PStruct('ask_tids',
-        PIndex('first'),
-        PIndex('last'),
-        PNumber('partition'),
-    )
+    AskTransactionInformation, AnswerTransactionInformation = request("""
+        Ask for transaction metadata.
 
-    _answer = PStruct('answer_tids',
-        PFTidList,
-    )
+        :nodes: C -> S
+        """)
 
-class TIDListFrom(Packet):
-    """
-    Ask for length TIDs starting at min_tid. The order of TIDs is ascending.
-    Used by `iterator`.
+    AskObjectHistory, AnswerObjectHistory = request("""
+        Ask history information for a given object. The order of serials is
+        descending, and the range is [first, last]. This maps to `history`.
 
-    :nodes: C -> S
-    """
-    _fmt = PStruct('tid_list_from',
-        PTID('min_tid'),
-        PTID('max_tid'),
-        PNumber('length'),
-        PNumber('partition'),
-    )
-
-    _answer = PStruct('answer_tids',
-        PFTidList,
-    )
-
-class TransactionInformation(Packet):
-    """
-    Ask for transaction metadata.
+        :nodes: C -> S
+        """)
 
-    :nodes: C -> S
-    """
-    _fmt = PStruct('ask_transaction_information',
-        PTID('tid'),
-    )
-
-    _answer = PStruct('answer_transaction_information',
-        PTID('tid'),
-        PString('user'),
-        PString('description'),
-        PString('extension'),
-        PBoolean('packed'),
-        PFOidList,
-    )
-
-class ObjectHistory(Packet):
-    """
-    Ask history information for a given object. The order of serials is
-    descending, and the range is [first, last]. This maps to `history`.
+    AskPartitionList, AnswerPartitionList = request("""
+        Ask information about partitions.
 
-    :nodes: C -> S
-    """
-    _fmt = PStruct('ask_object_history',
-        POID('oid'),
-        PIndex('first'),
-        PIndex('last'),
-    )
-
-    _answer = PStruct('answer_object_history',
-        POID('oid'),
-        PFHistoryList,
-    )
-
-class PartitionList(Packet):
-    """
-    Ask information about partitions.
+        :nodes: ctl -> A
+        """)
 
-    :nodes: ctl -> A
-    """
-    _fmt = PStruct('ask_partition_list',
-        PNumber('min_offset'),
-        PNumber('max_offset'),
-        PUUID('uuid'),
-    )
-
-    _answer = PStruct('answer_partition_list',
-        PPTID('ptid'),
-        PNumber('num_replicas'),
-        PFRowList,
-    )
-
-class NodeList(Packet):
-    """
-    Ask information about nodes.
+    AskNodeList, AnswerNodeList = request("""
+        Ask information about nodes.
 
-    :nodes: ctl -> A
-    """
-    _fmt = PStruct('ask_node_list',
-        PFNodeType,
-    )
+        :nodes: ctl -> A
+        """)
 
-    _answer = PStruct('answer_node_list',
-        PFNodeList,
-    )
+    SetNodeState = request("""
+        Change the state of a node.
 
-class SetNodeState(Packet):
-    """
-    Change the state of a node.
+        :nodes: ctl -> A -> M
+        """, error=True, ignore_when_closed=False)
 
-    :nodes: ctl -> A -> M
-    """
-    _fmt = PStruct('set_node_state',
-        PUUID('uuid'),
-        PFNodeState,
-    )
+    AddPendingNodes = request("""
+        Mark given pending nodes as running, for future inclusion when tweaking
+        the partition table.
 
-    _answer = Error
+        :nodes: ctl -> A -> M
+        """, error=True, ignore_when_closed=False)
 
-class AddPendingNodes(Packet):
-    """
-    Mark given pending nodes as running, for future inclusion when tweaking
-    the partition table.
+    TweakPartitionTable, AnswerTweakPartitionTable = request("""
+        Ask the master to balance the partition table, optionally excluding
+        specific nodes in anticipation of removing them.
 
-    :nodes: ctl -> A -> M
-    """
-    _fmt = PStruct('add_pending_nodes',
-        PFUUIDList,
-    )
+        :nodes: ctl -> A -> M
+        """)
 
-    _answer = Error
+    SetNumReplicas = request("""
+        Set the number of replicas.
 
-class TweakPartitionTable(Packet):
-    """
-    Ask the master to balance the partition table, optionally excluding
-    specific nodes in anticipation of removing them.
+        :nodes: ctl -> A -> M
+        """, error=True, ignore_when_closed=False)
 
-    :nodes: ctl -> A -> M
-    """
-    _fmt = PStruct('tweak_partition_table',
-        PBoolean('dry_run'),
-        PFUUIDList,
-    )
+    SetClusterState = request("""
+        Set the cluster state.
 
-    _answer = PStruct('answer_tweak_partition_table',
-        PBoolean('changed'),
-        PFRowList,
-    )
+        :nodes: ctl -> A -> M
+        """, error=True, ignore_when_closed=False)
 
-class NotifyNodeInformation(Packet):
-    """
-    Notify information about one or more nodes.
+    Repair = request("""
+        Ask storage nodes to repair their databases.
 
-    :nodes: M -> *
-    """
-    _fmt = PStruct('notify_node_informations',
-        PFloat('id_timestamp'),
-        PFNodeList,
-    )
+        :nodes: ctl -> A -> M
+        """, error=True)
 
-class SetNumReplicas(Packet):
-    """
-    Set the number of replicas.
+    NotifyRepair = notify("""
+        Repair is translated to this message, asking a specific storage node to
+        repair its database.
 
-    :nodes: ctl -> A -> M
-    """
-    _fmt = PStruct('set_num_replicas',
-        PNumber('num_replicas'),
-    )
+        :nodes: M -> S
+        """)
 
-    _answer = Error
+    NotifyClusterInformation = notify("""
+        Notify about a cluster state change.
 
-class SetClusterState(Packet):
-    """
-    Set the cluster state.
+        :nodes: M -> *
+        """)
 
-    :nodes: ctl -> A -> M
-    """
-    _fmt = PStruct('set_cluster_state',
-        PEnum('state', ClusterStates),
-    )
+    AskClusterState, AnswerClusterState = request("""
+        Ask the state of the cluster
 
-    _answer = Error
+        :nodes: ctl -> A; A -> M
+        """)
 
-class Repair(Packet):
-    """
-    Ask storage nodes to repair their databases.
+    AskObjectUndoSerial, AnswerObjectUndoSerial = request("""
+        Ask storage the serial where object data is when undoing given
+        transaction, for a list of OIDs.
 
-    :nodes: ctl -> A -> M
-    """
-    _flags = map(PBoolean, ('dry_run',
-        # 'prune_orphan' (commented because it's the only option for the moment)
-        ))
-    _fmt = PStruct('repair',
-        PFUUIDList,
-        *_flags)
+        Answer a dict mapping oids to 3-tuples:
+            current_serial (TID)
+                The latest serial visible to the undoing transaction.
+            undo_serial (TID)
+                Where undone data is (tid at which data is before given undo).
+            is_current (bool)
+                If current_serial's data is current on storage.
 
-    _answer = Error
+        :nodes: C -> S
+        """, allow_dict=True)
 
-class RepairOne(Packet):
-    """
-    Repair is translated to this message, asking a specific storage node to
-    repair its database.
+    AskTIDsFrom, AnswerTIDsFrom = request("""
+        Ask for length TIDs starting at min_tid. The order of TIDs is ascending.
+        Used by `iterator`.
 
-    :nodes: M -> S
-    """
-    _fmt = PStruct('repair', *Repair._flags)
+        :nodes: C -> S
+        """)
 
-class ClusterInformation(Packet):
-    """
-    Notify about a cluster state change.
+    AskPack, AnswerPack = request("""
+        Request a pack at given TID.
 
-    :nodes: M -> *
-    """
-    _fmt = PStruct('notify_cluster_information',
-        PEnum('state', ClusterStates),
-    )
+        :nodes: C -> M -> S
+        """, ignore_when_closed=False)
 
-class ClusterState(Packet):
-    """
-    Ask the state of the cluster
+    CheckReplicas = request("""
+        Ask the cluster to search for mismatches between replicas, metadata
+        only, and optionally within a specific range. Reference nodes can be
+        specified.
 
-    :nodes: ctl -> A; A -> M
-    """
+        :nodes: ctl -> A -> M
+        """, error=True, allow_dict=True)
 
-    _answer = PStruct('answer_cluster_state',
-        PEnum('state', ClusterStates),
-    )
+    CheckPartition = notify("""
+        Ask a storage node to compare a partition with all other nodes.
+        Like for CheckReplicas, only metadata are checked, optionally within a
+        specific range. A reference node can be specified.
 
-class ObjectUndoSerial(Packet):
-    """
-    Ask storage the serial where object data is when undoing given transaction,
-    for a list of OIDs.
+        :nodes: M -> S
+        """)
 
-    object_tid_dict has the following format:
-        key: oid
-        value: 3-tuple
-            current_serial (TID)
-                The latest serial visible to the undoing transaction.
-            undo_serial (TID)
-                Where undone data is (tid at which data is before given undo).
-            is_current (bool)
-                If current_serial's data is current on storage.
+    AskCheckTIDRange, AnswerCheckTIDRange = request("""
+        Ask some stats about a range of transactions.
+        Used to know if there are differences between a replicating node and
+        reference node.
 
-    :nodes: C -> S
-    """
-    _fmt = PStruct('ask_undo_transaction',
-        PTID('tid'),
-        PTID('ltid'),
-        PTID('undone_tid'),
-        PFOidList,
-    )
-
-    _answer = PStruct('answer_undo_transaction',
-        PDict('object_tid_dict',
-            POID('oid'),
-            PStruct('object_tid_value',
-                PTID('current_serial'),
-                PTID('undo_serial'),
-                PBoolean('is_current'),
-            ),
-        ),
-    )
-
-class CheckCurrentSerial(Packet):
-    """
-    Check if given serial is current for the given oid, and lock it so that
-    this state is not altered until transaction ends.
-    This maps to `checkCurrentSerialInTransaction`.
+        :nodes: S -> S
+        """)
 
-    :nodes: C -> S
-    """
-    _fmt = PStruct('ask_check_current_serial',
-        PTID('tid'),
-        POID('oid'),
-        PTID('serial'),
-    )
+    AskCheckSerialRange, AnswerCheckSerialRange = request("""
+        Ask some stats about a range of object history.
+        Used to know if there are differences between a replicating node and
+        reference node.
 
-    _answer = StoreObject._answer
+        :nodes: S -> S
+        """)
 
-class Pack(Packet):
-    """
-    Request a pack at given TID.
+    NotifyPartitionCorrupted = notify("""
+        Notify that mismatches were found while check replicas for a partition.
 
-    :nodes: C -> M -> S
-    """
-    _fmt = PStruct('ask_pack',
-        PTID('tid'),
-    )
+        :nodes: S -> M
+        """)
 
-    _answer = PStruct('answer_pack',
-        PBoolean('status'),
-    )
+    NotifyReady = notify("""
+        Notify that we're ready to serve requests.
 
-class CheckReplicas(Packet):
-    """
-    Ask the cluster to search for mismatches between replicas, metadata only,
-    and optionally within a specific range. Reference nodes can be specified.
+        :nodes: S -> M
+        """)
 
-    :nodes: ctl -> A -> M
-    """
-    _fmt = PStruct('check_replicas',
-        PDict('partition_dict',
-            PNumber('partition'),
-            PUUID('source'),
-        ),
-        PTID('min_tid'),
-        PTID('max_tid'),
-    )
-    _answer = Error
-
-class CheckPartition(Packet):
-    """
-    Ask a storage node to compare a partition with all other nodes.
-    Like for CheckReplicas, only metadata are checked, optionally within a
-    specific range. A reference node can be specified.
+    AskLastTransaction, AnswerLastTransaction = request("""
+        Ask last committed TID.
 
-    :nodes: M -> S
-    """
-    _fmt = PStruct('check_partition',
-        PNumber('partition'),
-        PStruct('source',
-            PString('upstream_name'),
-            PAddress('address'),
-        ),
-        PTID('min_tid'),
-        PTID('max_tid'),
-    )
-
-class CheckTIDRange(Packet):
-    """
-    Ask some stats about a range of transactions.
-    Used to know if there are differences between a replicating node and
-    reference node.
+        :nodes: C -> M; ctl -> A -> M
+        """, poll_thread=True)
 
-    :nodes: S -> S
-    """
-    _fmt = PStruct('ask_check_tid_range',
-        PNumber('partition'),
-        PNumber('length'),
-        PTID('min_tid'),
-        PTID('max_tid'),
-    )
-
-    _answer = PStruct('answer_check_tid_range',
-        PNumber('count'),
-        PChecksum('checksum'),
-        PTID('max_tid'),
-    )
-
-class CheckSerialRange(Packet):
-    """
-    Ask some stats about a range of object history.
-    Used to know if there are differences between a replicating node and
-    reference node.
+    AskCheckCurrentSerial, AnswerCheckCurrentSerial = request("""
+        Check if given serial is current for the given oid, and lock it so that
+        this state is not altered until transaction ends.
+        This maps to `checkCurrentSerialInTransaction`.
 
-    :nodes: S -> S
-    """
-    _fmt = PStruct('ask_check_serial_range',
-        PNumber('partition'),
-        PNumber('length'),
-        PTID('min_tid'),
-        PTID('max_tid'),
-        POID('min_oid'),
-    )
-
-    _answer = PStruct('answer_check_serial_range',
-        PNumber('count'),
-        PChecksum('tid_checksum'),
-        PTID('max_tid'),
-        PChecksum('oid_checksum'),
-        POID('max_oid'),
-    )
-
-class PartitionCorrupted(Packet):
-    """
-    Notify that mismatches were found while check replicas for a partition.
+        :nodes: C -> S
+        """)
 
-    :nodes: S -> M
-    """
-    _fmt = PStruct('partition_corrupted',
-        PNumber('partition'),
-        PList('cell_list',
-            PUUID('uuid'),
-        ),
-    )
-
-class LastTransaction(Packet):
-    """
-    Ask last committed TID.
+    NotifyTransactionFinished = notify("""
+        Notify that a transaction blocking a replication is now finished.
 
-    :nodes: C -> M; ctl -> A -> M
-    """
-    poll_thread = True
+        :nodes: M -> S
+        """)
 
-    _answer = PStruct('answer_last_transaction',
-        PTID('tid'),
-    )
+    Replicate = notify("""
+        Notify a storage node to replicate partitions up to given 'tid'
+        and from given sources.
 
-class NotifyReady(Packet):
-    """
-    Notify that we're ready to serve requests.
+        args: tid, upstream_name, {partition: address}
+        - upstream_name: replicate from an upstream cluster
+        - address: address of the source storage node, or None if there's
+                   no new data up to 'tid' for the given partition
 
-    :nodes: S -> M
-    """
+        :nodes: M -> S
+        """, allow_dict=True)
 
-class FetchTransactions(Packet):
-    """
-    Ask a storage node to send all transaction data we don't have,
-    and reply with the list of transactions we should not have.
+    NotifyReplicationDone = notify("""
+        Notify the master node that a partition has been successfully
+        replicated from a storage to another.
 
-    :nodes: S -> S
-    """
-    _fmt = PStruct('ask_transaction_list',
-        PNumber('partition'),
-        PNumber('length'),
-        PTID('min_tid'),
-        PTID('max_tid'),
-        PFTidList,           # already known transactions
-    )
-    _answer = PStruct('answer_transaction_list',
-        PTID('pack_tid'),
-        PTID('next_tid'),
-        PFTidList,           # transactions to delete
-    )
-
-class AddTransaction(Packet):
-    """
-    Send metadata of a transaction to a node that do not have them.
+        :nodes: S -> M
+        """)
 
-    :nodes: S -> S
-    """
-    nodelay = False
-
-    _fmt = PStruct('add_transaction',
-        PTID('tid'),
-        PString('user'),
-        PString('description'),
-        PString('extension'),
-        PBoolean('packed'),
-        PTID('ttid'),
-        PFOidList,
-    )
-
-class FetchObjects(Packet):
-    """
-    Ask a storage node to send object records we don't have,
-    and reply with the list of records we should not have.
+    AskFetchTransactions, AnswerFetchTransactions = request("""
+        Ask a storage node to send all transaction data we don't have,
+        and reply with the list of transactions we should not have.
 
-    :nodes: S -> S
-    """
-    _fmt = PStruct('ask_object_list',
-        PNumber('partition'),
-        PNumber('length'),
-        PTID('min_tid'),
-        PTID('max_tid'),
-        POID('min_oid'),
-        PDict('object_dict', # already known objects
-            PTID('serial'),
-            PFOidList,
-        ),
-    )
-    _answer = PStruct('answer_object_list',
-        PTID('pack_tid'),
-        PTID('next_tid'),
-        POID('next_oid'),
-        PDict('object_dict', # objects to delete
-            PTID('serial'),
-            PFOidList,
-        ),
-    )
-
-class AddObject(Packet):
-    """
-    Send an object record to a node that do not have it.
+        :nodes: S -> S
+        """)
 
-    :nodes: S -> S
-    """
-    nodelay = False
-
-    _fmt = PStruct('add_object',
-        POID('oid'),
-        PTID('serial'),
-        PBoolean('compression'),
-        PChecksum('checksum'),
-        PString('data'),
-        PTID('data_serial'),
-    )
-
-class Replicate(Packet):
-    """
-    Notify a storage node to replicate partitions up to given 'tid'
-    and from given sources.
+    AskFetchObjects, AnswerFetchObjects = request("""
+        Ask a storage node to send object records we don't have,
+        and reply with the list of records we should not have.
 
-    - upstream_name: replicate from an upstream cluster
-    - address: address of the source storage node, or None if there's no new
-               data up to 'tid' for the given partition
+        :nodes: S -> S
+        """, allow_dict=True)
 
-    :nodes: M -> S
-    """
-    _fmt = PStruct('replicate',
-        PTID('tid'),
-        PString('upstream_name'),
-        PDict('source_dict',
-            PNumber('partition'),
-            PAddress('address'),
-        )
-    )
-
-class ReplicationDone(Packet):
-    """
-    Notify the master node that a partition has been successfully replicated
-    from a storage to another.
+    AddTransaction = notify("""
+        Send metadata of a transaction to a node that does not have them.
 
-    :nodes: S -> M
-    """
-    _fmt = PStruct('notify_replication_done',
-        PNumber('offset'),
-        PTID('tid'),
-    )
+        :nodes: S -> S
+        """, nodelay=False)
 
-class Truncate(Packet):
-    """
-    Request DB to be truncated. Also used to leave backup mode.
+    AddObject = notify("""
+        Send an object record to a node that does not have it.
 
-    :nodes: ctl -> A -> M; M -> S
-    """
-    _fmt = PStruct('truncate',
-        PTID('tid'),
-    )
+        :nodes: S -> S
+        """, nodelay=False, data_path=(0, 2))
 
-    _answer = Error
+    Truncate = request("""
+        Request DB to be truncated. Also used to leave backup mode.
 
-class FlushLog(Packet):
-    """
-    Request all nodes to flush their logs.
+        :nodes: ctl -> A -> M; M -> S
+        """, error=True)
 
-    :nodes: ctl -> A -> M -> *
-    """
+    FlushLog = notify("""
+        Request all nodes to flush their logs.
 
+        :nodes: ctl -> A -> M -> *
+        """)
 
-_next_code = 0
-def register(request, ignore_when_closed=None):
-    """ Register a packet in the packet registry """
-    global _next_code
-    code = _next_code
-    assert code < RESPONSE_MASK
-    _next_code = code + 1
-    if request is Error:
-        code |= RESPONSE_MASK
-    # register the request
-    request._code = code
-    answer = request._answer
-    if ignore_when_closed is None:
-        # By default, on a closed connection:
-        # - request: ignore
-        # - answer: keep
-        # - notification: keep
-        ignore_when_closed = answer is not None
-    request._ignore_when_closed = ignore_when_closed
-    if answer in (Error, None):
-        return request
-    # build a class for the answer
-    answer = type('Answer' + request.__name__, (Packet, ), {})
-    answer._fmt = request._answer
-    answer.poll_thread = request.poll_thread
-    answer._request = request
-    assert answer._code is None, "Answer of %s is already used" % (request, )
-    answer._code = code | RESPONSE_MASK
-    request._answer = answer
-    return request, answer
+    del notify, request
 
-class Packets(dict):
-    """
-    Packet registry that checks packet code uniqueness and provides an index
-    """
-    def __metaclass__(name, base, d):
-        # this builds a "singleton"
-        cls = type('PacketRegistry', base, d)()
-        for k, v in d.iteritems():
-            if isinstance(v, type) and issubclass(v, Packet):
-                v.handler_method_name = k[0].lower() + k[1:]
-                cls[v._code] = v
-        return cls
-
-    Error = register(
-                    Error)
-    RequestIdentification, AcceptIdentification = register(
-                    RequestIdentification, ignore_when_closed=True)
-    Ping, Pong = register(
-                    Ping)
-    CloseClient  = register(
-                    CloseClient)
-    AskPrimary, AnswerPrimary = register(
-                    PrimaryMaster)
-    NotPrimaryMaster = register(
-                    NotPrimaryMaster)
-    NotifyNodeInformation = register(
-                    NotifyNodeInformation)
-    AskRecovery, AnswerRecovery = register(
-                    Recovery)
-    AskLastIDs, AnswerLastIDs = register(
-                    LastIDs)
-    AskPartitionTable, AnswerPartitionTable = register(
-                    PartitionTable)
-    SendPartitionTable = register(
-                    NotifyPartitionTable)
-    NotifyPartitionChanges = register(
-                    PartitionChanges)
-    StartOperation = register(
-                    StartOperation)
-    StopOperation = register(
-                    StopOperation)
-    AskUnfinishedTransactions, AnswerUnfinishedTransactions = register(
-                    UnfinishedTransactions)
-    AskLockedTransactions, AnswerLockedTransactions = register(
-                    LockedTransactions)
-    AskFinalTID, AnswerFinalTID = register(
-                    FinalTID)
-    ValidateTransaction = register(
-                    ValidateTransaction)
-    AskBeginTransaction, AnswerBeginTransaction = register(
-                    BeginTransaction)
-    FailedVote = register(
-                    FailedVote)
-    AskFinishTransaction, AnswerTransactionFinished = register(
-                    FinishTransaction, ignore_when_closed=False)
-    AskLockInformation, AnswerInformationLocked = register(
-                    LockInformation, ignore_when_closed=False)
-    InvalidateObjects = register(
-                    InvalidateObjects)
-    NotifyUnlockInformation = register(
-                    UnlockInformation)
-    AskNewOIDs, AnswerNewOIDs = register(
-                    GenerateOIDs)
-    NotifyDeadlock = register(
-                    Deadlock)
-    AskRebaseTransaction, AnswerRebaseTransaction = register(
-                    RebaseTransaction)
-    AskRebaseObject, AnswerRebaseObject = register(
-                    RebaseObject)
-    AskStoreObject, AnswerStoreObject = register(
-                    StoreObject)
-    AbortTransaction = register(
-                    AbortTransaction)
-    AskStoreTransaction, AnswerStoreTransaction = register(
-                    StoreTransaction)
-    AskVoteTransaction, AnswerVoteTransaction = register(
-                    VoteTransaction)
-    AskObject, AnswerObject = register(
-                    GetObject)
-    AskTIDs, AnswerTIDs = register(
-                    TIDList)
-    AskTransactionInformation, AnswerTransactionInformation = register(
-                    TransactionInformation)
-    AskObjectHistory, AnswerObjectHistory = register(
-                    ObjectHistory)
-    AskPartitionList, AnswerPartitionList = register(
-                    PartitionList)
-    AskNodeList, AnswerNodeList = register(
-                    NodeList)
-    SetNodeState = register(
-                    SetNodeState, ignore_when_closed=False)
-    AddPendingNodes = register(
-                    AddPendingNodes, ignore_when_closed=False)
-    TweakPartitionTable, AnswerTweakPartitionTable = register(
-                    TweakPartitionTable)
-    SetNumReplicas = register(
-                    SetNumReplicas, ignore_when_closed=False)
-    SetClusterState = register(
-                    SetClusterState, ignore_when_closed=False)
-    Repair = register(
-                    Repair)
-    NotifyRepair = register(
-                    RepairOne)
-    NotifyClusterInformation = register(
-                    ClusterInformation)
-    AskClusterState, AnswerClusterState = register(
-                    ClusterState)
-    AskObjectUndoSerial, AnswerObjectUndoSerial = register(
-                    ObjectUndoSerial)
-    AskTIDsFrom, AnswerTIDsFrom = register(
-                    TIDListFrom)
-    AskPack, AnswerPack = register(
-                    Pack, ignore_when_closed=False)
-    CheckReplicas = register(
-                    CheckReplicas)
-    CheckPartition = register(
-                    CheckPartition)
-    AskCheckTIDRange, AnswerCheckTIDRange = register(
-                    CheckTIDRange)
-    AskCheckSerialRange, AnswerCheckSerialRange = register(
-                    CheckSerialRange)
-    NotifyPartitionCorrupted = register(
-                    PartitionCorrupted)
-    NotifyReady = register(
-                    NotifyReady)
-    AskLastTransaction, AnswerLastTransaction = register(
-                    LastTransaction)
-    AskCheckCurrentSerial, AnswerCheckCurrentSerial = register(
-                    CheckCurrentSerial)
-    NotifyTransactionFinished = register(
-                    NotifyTransactionFinished)
-    Replicate = register(
-                    Replicate)
-    NotifyReplicationDone = register(
-                    ReplicationDone)
-    AskFetchTransactions, AnswerFetchTransactions = register(
-                    FetchTransactions)
-    AskFetchObjects, AnswerFetchObjects = register(
-                    FetchObjects)
-    AddTransaction = register(
-                    AddTransaction)
-    AddObject = register(
-                    AddObject)
-    Truncate = register(
-                    Truncate)
-    FlushLog = register(
-                    FlushLog)
 
 def Errors():
     registry_dict = {}
     handler_method_name_dict = {}
+    Error = Packets.Error
     def register_error(code):
         return lambda self, message='': Error(code, message)
     for error in ErrorCodes:
@@ -1856,19 +854,20 @@ from operator import itemgetter
 
 def formatNodeList(node_list, prefix='', _sort_key=itemgetter(2)):
     if node_list:
-        node_list.sort(key=_sort_key)
         node_list = [(
                 uuid_str(uuid), str(node_type),
                 ('[%s]:%s' if ':' in addr[0] else '%s:%s')
                 % addr if addr else '', str(state),
                 str(id_timestamp and datetime.utcfromtimestamp(id_timestamp)))
-            for node_type, addr, uuid, state, id_timestamp in node_list]
+            for node_type, addr, uuid, state, id_timestamp
+                in sorted(node_list, key=_sort_key)]
         t = ''.join('%%-%us | ' % max(len(x[i]) for x in node_list)
                     for i in xrange(len(node_list[0]) - 1))
         return map((prefix + t + '%s').__mod__, node_list)
     return ()
 
-NotifyNodeInformation._neolog = staticmethod(lambda timestamp, node_list:
+Packets.NotifyNodeInformation._neolog = staticmethod(
+    lambda timestamp, node_list:
     ((timestamp,), formatNodeList(node_list, ' ! ')))
 
-Error._neolog = staticmethod(lambda *args: ((), ("%s (%s)" % args,)))
+Packets.Error._neolog = staticmethod(lambda *args: ((), ("%s (%s)" % args,)))

neo/lib/util.py

@@ -166,65 +166,6 @@ def parseMasterList(masters):
     return map(parseNodeAddress, masters.split())
 
 
-class ReadBuffer(object):
-    """
-        Implementation of a lazy buffer. Main purpose if to reduce useless
-        copies of data by storing chunks and join them only when the requested
-        size is available.
-
-        TODO: For better performance, use:
-        - socket.recv_into (64kiB blocks)
-        - struct.unpack_from
-        - and a circular buffer of dynamic size (initial size:
-          twice the length passed to socket.recv_into ?)
-        """
-
-    def __init__(self):
-        self.size = 0
-        self.content = deque()
-
-    def append(self, data):
-        """ Append some data and compute the new buffer size """
-        self.size += len(data)
-        self.content.append(data)
-
-    def __len__(self):
-        """ Return the current buffer size """
-        return self.size
-
-    def read(self, size):
-        """ Read and consume size bytes """
-        if self.size < size:
-            return None
-        self.size -= size
-        chunk_list = []
-        pop_chunk = self.content.popleft
-        append_data = chunk_list.append
-        to_read = size
-        # select required chunks
-        while to_read > 0:
-            chunk_data = pop_chunk()
-            to_read -= len(chunk_data)
-            append_data(chunk_data)
-        if to_read < 0:
-            # too many bytes consumed, cut the last chunk
-            last_chunk = chunk_list[-1]
-            keep, let = last_chunk[:to_read], last_chunk[to_read:]
-            self.content.appendleft(let)
-            chunk_list[-1] = keep
-        # join all chunks (one copy)
-        data = ''.join(chunk_list)
-        assert len(data) == size
-        return data
-
-    def clear(self):
-        """ Erase all buffer content """
-        self.size = 0
-        self.content.clear()
-
-dummy_read_buffer = ReadBuffer()
-dummy_read_buffer.append = lambda _: None
-
 class cached_property(object):
     """
     A property that is only computed once per instance and then replaces itself

neo/master/app.py

@@ -585,7 +585,9 @@ class Application(BaseApplication):
         self.tm.executeQueuedEvents()
 
     def startStorage(self, node):
-        node.send(Packets.StartOperation(self.backup_tid))
+        # XXX: Is this boolean 'backup' field needed ?
+        #      Maybe this can be deduced from cluster state.
+        node.send(Packets.StartOperation(bool(self.backup_tid)))
         uuid = node.getUUID()
         assert uuid not in self.storage_starting_set
         assert uuid not in self.storage_ready_dict

neo/scripts/neolog.py

@@ -157,27 +157,49 @@ class Log(object):
         for x in 'uuid_str', 'Packets', 'PacketMalformedError':
             setattr(self, x, g[x])
         x = {}
+        try:
+            Unpacker = g['Unpacker']
+        except KeyError:
+            unpackb = None
+        else:
+            from msgpack import ExtraData, UnpackException
+            def unpackb(data):
+                u = Unpacker()
+                u.feed(data)
+                data = u.unpack()
+                if u.read_bytes(1):
+                    raise ExtraData
+                return data
+            self.PacketMalformedError = UnpackException
+        self.unpackb = unpackb
         if self._decode > 1:
-            PStruct = g['PStruct']
-            PBoolean = g['PBoolean']
-            def hasData(item):
-                items = item._items
-                for i, item in enumerate(items):
-                    if isinstance(item, PStruct):
-                        j = hasData(item)
-                        if j:
-                            return (i,) + j
-                    elif (isinstance(item, PBoolean)
-                          and item._name == 'compression'
-                          and i + 2 < len(items)
-                          and items[i+2]._name == 'data'):
-                        return i,
-            for p in self.Packets.itervalues():
-                if p._fmt is not None:
-                    path = hasData(p._fmt)
-                    if path:
-                        assert not hasattr(p, '_neolog'), p
-                        x[p._code] = path
+            try:
+                PStruct = g['PStruct']
+            except KeyError:
+                for p in self.Packets.itervalues():
+                    data_path = getattr(p, 'data_path', (None,))
+                    if p._code >> 15 == data_path[0]:
+                        x[p._code] = data_path[1:]
+            else:
+                PBoolean = g['PBoolean']
+                def hasData(item):
+                    items = item._items
+                    for i, item in enumerate(items):
+                        if isinstance(item, PStruct):
+                            j = hasData(item)
+                            if j:
+                                return (i,) + j
+                        elif (isinstance(item, PBoolean)
+                              and item._name == 'compression'
+                              and i + 2 < len(items)
+                              and items[i+2]._name == 'data'):
+                            return i,
+                for p in self.Packets.itervalues():
+                    if p._fmt is not None:
+                        path = hasData(p._fmt)
+                        if path:
+                            assert not hasattr(p, '_neolog'), p
+                            x[p._code] = path
         self._getDataPath = x.get
 
         try:
@@ -215,11 +237,13 @@ class Log(object):
         if body is not None:
             log = getattr(p, '_neolog', None)
             if log or self._decode:
-                p = p()
-                p._id = msg_id
-                p._body = body
                 try:
-                    args = p.decode()
+                    if self.unpackb:
+                        args = self.unpackb(body)
+                    else:
+                        p = p()
+                        p._body = body
+                        args = p.decode()
                 except self.PacketMalformedError:
                     msg.append("Can't decode packet")
                 else:

neo/storage/database/sqlite.py

@@ -461,8 +461,12 @@ class SQLiteDatabaseManager(DatabaseManager):
         return r
 
     def loadData(self, data_id):
-        return self.query("SELECT compression, hash, value"
-                          " FROM data WHERE id=?", (data_id,)).fetchone()
+        compression, checksum, data = self.query(
+            "SELECT compression, hash, value  FROM data WHERE id=?",
+            (data_id,)).fetchone()
+        if checksum:
+            return compression, str(checksum), str(data)
+        return compression, checksum, data
 
     def _getDataTID(self, oid, tid=None, before_tid=None):
         partition = self._getReadablePartition(oid)

neo/storage/handlers/client.py

@@ -53,7 +53,7 @@ class ClientOperationHandler(BaseHandler):
             p = Errors.TidNotFound('%s does not exist' % dump(tid))
         else:
             p = Packets.AnswerTransactionInformation(tid, t[1], t[2], t[3],
-                    t[4], t[0])
+                    bool(t[4]), t[0])
         conn.answer(p)
 
     def getEventQueue(self):

neo/storage/handlers/storage.py

@@ -212,7 +212,7 @@ class StorageOperationHandler(EventHandler):
                         # Sending such packet does not mark the connection
                         # for writing if there's too little data in the buffer.
                         conn.send(Packets.AddTransaction(tid, user,
-                            desc, ext, packed, ttid, oid_list), msg_id)
+                            desc, ext, bool(packed), ttid, oid_list), msg_id)
                         # To avoid delaying several connections simultaneously,
                         # and also prevent the backend from scanning different
                         # parts of the DB at the same time, we ask the
@@ -248,7 +248,7 @@ class StorageOperationHandler(EventHandler):
                 for serial, oid in object_list:
                     oid_set = object_dict.get(serial)
                     if oid_set:
-                        if type(oid_set) is list:
+                        if type(oid_set) is tuple:
                             object_dict[serial] = oid_set = set(oid_set)
                         if oid in oid_set:
                             oid_set.remove(oid)

neo/tests/master/testClientHandler.py

@@ -71,7 +71,7 @@ class MasterClientHandlerTests(NeoUnitTestBase):
         self.app.nm.getByUUID(storage_uuid).setConnection(storage_conn)
         self.service.askPack(conn, tid)
         self.checkNoPacketSent(conn)
-        ptid = self.checkAskPacket(storage_conn, Packets.AskPack).decode()[0]
+        ptid = self.checkAskPacket(storage_conn, Packets.AskPack)._args[0]
         self.assertEqual(ptid, tid)
         self.assertTrue(self.app.packing[0] is conn)
         self.assertEqual(self.app.packing[1], peer_id)
@@ -83,7 +83,7 @@ class MasterClientHandlerTests(NeoUnitTestBase):
         self.app.nm.getByUUID(storage_uuid).setConnection(storage_conn)
         self.service.askPack(conn, tid)
         self.checkNoPacketSent(storage_conn)
-        status = self.checkAnswerPacket(conn, Packets.AnswerPack).decode()[0]
+        status = self.checkAnswerPacket(conn, Packets.AnswerPack)._args[0]
         self.assertFalse(status)
 
 if __name__ == '__main__':

neo/tests/master/testStorageHandler.py

@@ -72,7 +72,7 @@ class MasterStorageHandlerTests(NeoUnitTestBase):
         self.service.answerPack(conn2, False)
         packet = self.checkNotifyPacket(client_conn, Packets.AnswerPack)
         # TODO: verify packet peer id
-        self.assertTrue(packet.decode()[0])
+        self.assertTrue(packet._args[0])
         self.assertEqual(self.app.packing, None)
 
 if __name__ == '__main__':

neo/tests/testHandler.py

@@ -33,9 +33,9 @@ class HandlerTests(NeoUnitTestBase):
 
     def getFakePacket(self):
         p = Mock({
-            'decode': (),
             '__repr__': 'Fake Packet',
         })
+        p._args = ()
         p.handler_method_name = 'fake_method'
         return p
 
@@ -53,13 +53,6 @@ class HandlerTests(NeoUnitTestBase):
         self.handler.dispatch(conn, packet)
         self.checkErrorPacket(conn)
         self.checkAborted(conn)
-        # raise PacketMalformedError
-        conn.mockCalledMethods = {}
-        def fake(c):
-            raise PacketMalformedError('message')
-        self.setFakeMethod(fake)
-        self.handler.dispatch(conn, packet)
-        self.checkClosed(conn)
         # raise NotReadyError
         conn.mockCalledMethods = {}
         def fake(c):

neo/tests/testUtil.py

@@ -17,7 +17,7 @@
 import unittest
 import socket
 from . import NeoUnitTestBase
-from neo.lib.util import ReadBuffer, parseNodeAddress
+from neo.lib.util import parseNodeAddress
 
 class UtilTests(NeoUnitTestBase):
 
@@ -40,24 +40,6 @@ class UtilTests(NeoUnitTestBase):
         self.assertIn(parseNodeAddress('localhost'), local_address(0))
         self.assertIn(parseNodeAddress('localhost:10'), local_address(10))
 
-    def testReadBufferRead(self):
-        """ Append some chunk then consume the data """
-        buf = ReadBuffer()
-        self.assertEqual(len(buf), 0)
-        buf.append('abc')
-        self.assertEqual(len(buf), 3)
-        # no enough data
-        self.assertEqual(buf.read(4), None)
-        self.assertEqual(len(buf), 3)
-        buf.append('def')
-        # consume a part
-        self.assertEqual(len(buf), 6)
-        self.assertEqual(buf.read(4), 'abcd')
-        self.assertEqual(len(buf), 2)
-        # consume the rest
-        self.assertEqual(buf.read(3), None)
-        self.assertEqual(buf.read(2), 'ef')
-
 if __name__ == "__main__":
     unittest.main()
 

neo/tests/threaded/test.py

@@ -1340,7 +1340,7 @@ class Test(NEOThreadedTest):
             # Also check that the master reset the last oid to a correct value.
             t.begin()
             self.assertEqual(1, u64(c.root()['x']._p_oid))
-            self.assertFalse(cluster.client.new_oid_list)
+            self.assertFalse(cluster.client.new_oids)
             self.assertEqual(2, u64(cluster.client.new_oid()))
 
     @with_cluster()
@@ -2106,7 +2106,7 @@ class Test(NEOThreadedTest):
                     except threading.ThreadError:
                         l[j].acquire()
                         threads[j-1].start()
-                    if x != 'StoreTransaction':
+                    if x != 'AskStoreTransaction':
                         try:
                             l[i].acquire()
                         except IndexError:
@@ -2183,15 +2183,16 @@ class Test(NEOThreadedTest):
         x = self._testComplexDeadlockAvoidanceWithOneStorage(changes,
             (1, 1, 0, 1, 2, 2, 2, 2, 0, 1, 2, 1, 0, 0, 1, 0, 0, 1),
             ('tpc_begin', 'tpc_begin', 1, 2, 3, 'tpc_begin', 1, 2, 4, 3, 4,
-             'StoreTransaction', 'RebaseTransaction', 'RebaseTransaction',
-             'AnswerRebaseTransaction', 'AnswerRebaseTransaction',
-             'RebaseTransaction', 'AnswerRebaseTransaction'),
+             'AskStoreTransaction', 'AskRebaseTransaction',
+             'AskRebaseTransaction', 'AnswerRebaseTransaction',
+             'AnswerRebaseTransaction', 'AskRebaseTransaction',
+             'AnswerRebaseTransaction'),
             [4, 6, 2, 6])
         try:
             x[1].remove(1)
         except ValueError:
             pass
-        self.assertEqual(x, {0: [2, 'StoreTransaction'], 1: ['tpc_abort']})
+        self.assertEqual(x, {0: [2, 'AskStoreTransaction'], 1: ['tpc_abort']})
 
     def testCascadedDeadlockAvoidanceWithOneStorage2(self):
         def changes(r1, r2, r3):
@@ -2214,8 +2215,8 @@ class Test(NEOThreadedTest):
                 (0, 1, 1, 0, 1, 2, 2, 2, 2, 0, 1, 2, 1,
                  0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 1),
                 ('tpc_begin', 1, 'tpc_begin', 1, 2, 3, 'tpc_begin',
-                 2, 3, 4, 3, 4, 'StoreTransaction', 'RebaseTransaction',
-                 'RebaseTransaction', 'AnswerRebaseTransaction'),
+                 2, 3, 4, 3, 4, 'AskStoreTransaction', 'AskRebaseTransaction',
+                 'AskRebaseTransaction', 'AnswerRebaseTransaction'),
                 [1, 7, 9, 0])
         x[0].sort(key=str)
         try:
@@ -2224,8 +2225,8 @@ class Test(NEOThreadedTest):
             pass
         self.assertEqual(x, {
             0: [2, 3, 'AnswerRebaseTransaction',
-                'RebaseTransaction', 'StoreTransaction'],
-            1: ['AnswerRebaseTransaction','RebaseTransaction',
+                'AskRebaseTransaction', 'AskStoreTransaction'],
+            1: ['AnswerRebaseTransaction','AskRebaseTransaction',
                 'AnswerRebaseTransaction', 'tpc_abort'],
         })
 
@@ -2258,7 +2259,7 @@ class Test(NEOThreadedTest):
         end = self._testComplexDeadlockAvoidanceWithOneStorage(changes,
             (0, 1, 1, 0, 1, 1, 0, 0, 2, 2, 2, 2, 1, vote_t2, tic_t1),
             ('tpc_begin', 1) * 2, [3, 0, 0, 0], None)
-        self.assertLessEqual(2, end[0].count('RebaseTransaction'))
+        self.assertLessEqual(2, end[0].count('AskRebaseTransaction'))
 
     def testFailedConflictOnBigValueDuringDeadlockAvoidance(self):
         def changes(r1, r2, r3):
@@ -2274,10 +2275,10 @@ class Test(NEOThreadedTest):
             x = self._testComplexDeadlockAvoidanceWithOneStorage(changes,
                 (1, 1, 1, 2, 2, 2, 1, 2, 2, 0, 0, 1, 1, 1, 0),
                 ('tpc_begin', 'tpc_begin', 1, 2, 'tpc_begin', 1, 3, 3, 4,
-                'StoreTransaction', 2, 4, 'RebaseTransaction',
+                'AskStoreTransaction', 2, 4, 'AskRebaseTransaction',
                 'AnswerRebaseTransaction', 'tpc_abort'),
                 [5, 1, 0, 2], POSException.ConflictError)
-        self.assertEqual(x, {0: ['StoreTransaction']})
+        self.assertEqual(x, {0: ['AskStoreTransaction']})
 
     @with_cluster(replicas=1, partitions=4)
     def testNotifyReplicated(self, cluster):
@@ -2364,7 +2365,7 @@ class Test(NEOThreadedTest):
         def delayConflict(conn, packet):
             app = self.getConnectionApp(conn)
             if (isinstance(packet, Packets.AnswerStoreObject)
-                and packet.decode()[0]):
+                and packet._args[0]):
                 conn, = cluster.client.getConnectionList(app)
                 kw = conn._handlers._pending[0][0][packet._id][1]
                 return 1 == u64(kw['oid']) and delay_conflict[app.uuid].pop()
@@ -2382,8 +2383,9 @@ class Test(NEOThreadedTest):
              self.thread_switcher(threads,
                 (1, 2, 3, 0, 1, 0, 2, t3_c, 1, 3, 2, t3_resolve, 0, 0, 0,
                  t1_rebase, 2, t3_b, 3, t4_d, 0, 2, 2),
-                ('tpc_begin', 'tpc_begin', 'tpc_begin', 'tpc_begin', 2, 1, 1,
-                 3, 3, 4, 4, 3, 1, 'RebaseTransaction', 'RebaseTransaction',
+                ('tpc_begin', 'tpc_begin', 'tpc_begin', 'tpc_begin',
+                 2, 1, 1, 3, 3, 4, 4, 3, 1,
+                 'AskRebaseTransaction', 'AskRebaseTransaction',
                  'AnswerRebaseTransaction', 'AnswerRebaseTransaction', 2
                  )) as end:
             delay = f.delayAskFetchTransactions()
@@ -2395,11 +2397,11 @@ class Test(NEOThreadedTest):
         t4.begin()
         self.assertEqual([15, 11, 13, 16], [r[x].value for x in 'abcd'])
         self.assertEqual([2, 2], map(end.pop(2).count,
-            ['RebaseTransaction', 'AnswerRebaseTransaction']))
+            ['AskRebaseTransaction', 'AnswerRebaseTransaction']))
         self.assertEqual(end, {
-            0: [1, 'StoreTransaction'],
-            1: ['StoreTransaction'],
-            3: [4, 'StoreTransaction'],
+            0: [1, 'AskStoreTransaction'],
+            1: ['AskStoreTransaction'],
+            3: [4, 'AskStoreTransaction'],
         })
         self.assertFalse(s1.dm.getOrphanList())
 
@@ -2435,7 +2437,8 @@ class Test(NEOThreadedTest):
              self.thread_switcher((thread,),
                  (1, 0, 1, 1, t2_b, 0, 0, 1, t2_vote, 0, 0),
                  ('tpc_begin', 'tpc_begin', 1, 1, 2, 2,
-                  'RebaseTransaction', 'RebaseTransaction', 'StoreTransaction',
+                  'AskRebaseTransaction', 'AskRebaseTransaction',
+                  'AskStoreTransaction',
                   'AnswerRebaseTransaction', 'AnswerRebaseTransaction',
                   )) as end:
             delay = f.delayAskFetchTransactions()
@@ -2498,9 +2501,10 @@ class Test(NEOThreadedTest):
                 with self.thread_switcher((commit23,),
                     (1, 1, 0, 0, t1_rebase, 0, 0, 0, 1, 1, 1, 1, 0),
                     ('tpc_begin', 'tpc_begin', 0, 1, 0,
-                      'RebaseTransaction', 'RebaseTransaction',
-                      'AnswerRebaseTransaction', 'AnswerRebaseTransaction',
-                      'StoreTransaction', 'tpc_begin', 1, 'tpc_abort')) as end:
+                     'AskRebaseTransaction', 'AskRebaseTransaction',
+                     'AnswerRebaseTransaction', 'AnswerRebaseTransaction',
+                     'AskStoreTransaction', 'tpc_begin', 1, 'tpc_abort',
+                     )) as end:
                     self.assertRaises(POSException.ConflictError, t1.commit)
                     commit23.join()
         self.assertEqual(end, {0: ['tpc_abort']})
@@ -2587,9 +2591,9 @@ class Test(NEOThreadedTest):
                  self.thread_switcher((commit2,),
                 (1, 1, 0, 0, t1_b, t1_resolve, 0, 0, 0, 0, 1, t2_vote, t1_end),
                 ('tpc_begin', 'tpc_begin', 2, 1, 2, 1, 1,
-                 'RebaseTransaction', 'RebaseTransaction',
+                 'AskRebaseTransaction', 'AskRebaseTransaction',
                  'AnswerRebaseTransaction', 'AnswerRebaseTransaction',
-                 'StoreTransaction')) as end:
+                 'AskStoreTransaction')) as end:
                 t1.commit()
                 commit2.join()
         t1.begin()
@@ -2597,7 +2601,7 @@ class Test(NEOThreadedTest):
         self.assertEqual(r['a'].value, 9)
         self.assertEqual(r['b'].value, 6)
         t1 = end.pop(0)
-        self.assertEqual(t1.pop(), 'StoreTransaction')
+        self.assertEqual(t1.pop(), 'AskStoreTransaction')
         self.assertEqual(sorted(t1), [1, 2])
         self.assertFalse(end)
         self.assertPartitionTable(cluster, 'UU|UU')
@@ -2699,9 +2703,9 @@ class Test(NEOThreadedTest):
             with Patch(cluster.client, _loadFromStorage=load) as p, \
                  self.thread_switcher((commit2,),
                 (1, 0, tic1, 0, t1_resolve, 1, t2_begin, 0, 1, 1, 0),
-                ('tpc_begin', 'tpc_begin', 1, 1, 1, 'StoreTransaction',
-                 'tpc_begin', 'RebaseTransaction', 'RebaseTransaction', 1,
-                 'StoreTransaction')) as end:
+                ('tpc_begin', 'tpc_begin', 1, 1, 1, 'AskStoreTransaction',
+                 'tpc_begin', 'AskRebaseTransaction', 'AskRebaseTransaction',
+                 1, 'AskStoreTransaction')) as end:
                 self.assertRaisesRegexp(NEOStorageError,
                                         '^partition 0 not fully write-locked$',
                                         t1.commit)
@@ -2754,13 +2758,14 @@ class Test(NEOThreadedTest):
                 f.remove(delayFinish)
             with self.thread_switcher((commit2,),
                 (1, 0, 0, 1, t2_b, 0, t1_resolve),
-                ('tpc_begin', 'tpc_begin', 0, 2, 2, 'StoreTransaction')) as end:
+                ('tpc_begin', 'tpc_begin', 0, 2, 2, 'AskStoreTransaction')
+                ) as end:
                 t1.commit()
                 commit2.join()
         t1.begin()
         self.assertEqual(c1.root()['b'].value, 6)
         self.assertPartitionTable(cluster, 'UU|UU')
-        self.assertEqual(end, {0: [2, 2, 'StoreTransaction']})
+        self.assertEqual(end, {0: [2, 2, 'AskStoreTransaction']})
         self.assertFalse(s1.dm.getOrphanList())
 
     @with_cluster(storage_count=2, partitions=2)
@@ -2783,19 +2788,19 @@ class Test(NEOThreadedTest):
             yield 1
             self.tic()
         with self.thread_switcher((t,), (1, 0, 1, 0, t1_b, 0, 0, 0, 1),
-            ('tpc_begin', 'tpc_begin', 1, 3, 3, 1, 'RebaseTransaction',
+            ('tpc_begin', 'tpc_begin', 1, 3, 3, 1, 'AskRebaseTransaction',
              2, 'AnswerRebaseTransaction')) as end:
             t1.commit()
             t.join()
         t2.begin()
         self.assertEqual([6, 9, 6], [r[x].value for x in 'abc'])
         self.assertEqual([2, 2], map(end.pop(1).count,
-            ['RebaseTransaction', 'AnswerRebaseTransaction']))
+            ['AskRebaseTransaction', 'AnswerRebaseTransaction']))
         # Rarely, there's an extra deadlock for t1:
-        # 0: ['AnswerRebaseTransaction', 'RebaseTransaction',
-        #     'RebaseTransaction', 'AnswerRebaseTransaction',
+        # 0: ['AnswerRebaseTransaction', 'AskRebaseTransaction',
+        #     'AskRebaseTransaction', 'AnswerRebaseTransaction',
         #     'AnswerRebaseTransaction', 2, 3, 1,
-        #     'StoreTransaction', 'VoteTransaction']
+        #     'AskStoreTransaction', 'VoteTransaction']
         self.assertEqual(end.pop(0)[0], 'AnswerRebaseTransaction')
         self.assertFalse(end)
 
@@ -2825,13 +2830,13 @@ class Test(NEOThreadedTest):
         threads = map(self.newPausedThread, (t2.commit, t3.commit))
         with self.thread_switcher(threads, (1, 2, 0, 1, 2, 1, 0, 2, 0, 1, 2),
             ('tpc_begin', 'tpc_begin', 'tpc_begin', 1, 2, 3, 4, 4, 4,
-             'RebaseTransaction', 'StoreTransaction')) as end:
+             'AskRebaseTransaction', 'AskStoreTransaction')) as end:
             t1.commit()
             for t in threads:
                 t.join()
         self.assertEqual(end, {
-            0: ['AnswerRebaseTransaction', 'StoreTransaction'],
-            2: ['StoreTransaction']})
+            0: ['AnswerRebaseTransaction', 'AskStoreTransaction'],
+            2: ['AskStoreTransaction']})
 
     @with_cluster(replicas=1)
     def testConflictAfterDeadlockWithSlowReplica1(self, cluster,
@@ -2874,16 +2879,16 @@ class Test(NEOThreadedTest):
                 order[-1] = t1_resolve
                 delay = f.delayAskStoreObject()
             with self.thread_switcher((t,), order,
-                ('tpc_begin', 'tpc_begin', 1, 1, 2, 2, 'RebaseTransaction',
-                'RebaseTransaction', 'AnswerRebaseTransaction',
-                'StoreTransaction')) as end:
+                ('tpc_begin', 'tpc_begin', 1, 1, 2, 2, 'AskRebaseTransaction',
+                'AskRebaseTransaction', 'AnswerRebaseTransaction',
+                'AskStoreTransaction')) as end:
                 t1.commit()
                 t.join()
             self.assertNotIn(delay, f)
             t2.begin()
             end[0].sort(key=str)
             self.assertEqual(end, {0: [1, 'AnswerRebaseTransaction',
-                                       'StoreTransaction']})
+                                       'AskStoreTransaction']})
             self.assertEqual([4, 2], [r[x].value for x in 'ab'])
 
     def testConflictAfterDeadlockWithSlowReplica2(self):
@@ -2934,7 +2939,7 @@ class Test(NEOThreadedTest):
             with ConnectionFilter() as f:
                 f.add(lambda conn, packet:
                     isinstance(packet, Packets.RequestIdentification)
-                    and packet.decode()[0] == NodeTypes.STORAGE)
+                    and packet._args[0] == NodeTypes.STORAGE)
                 self.tic()
                 m2.start()
                 self.tic()
@@ -2974,7 +2979,7 @@ class Test(NEOThreadedTest):
         with ConnectionFilter() as f:
             f.add(lambda conn, packet:
                 isinstance(packet, Packets.RequestIdentification)
-                and packet.decode()[0] == NodeTypes.MASTER)
+                and packet._args[0] == NodeTypes.MASTER)
             cluster.start(recovering=True)
             neoctl = cluster.neoctl
             getClusterState = neoctl.getClusterState

neo/tests/threaded/testReplication.py

@@ -113,7 +113,7 @@ class ReplicationTests(NEOThreadedTest):
             importZODB(3)
             def delaySecondary(conn, packet):
                 if isinstance(packet, Packets.Replicate):
-                    tid, upstream_name, source_dict = packet.decode()
+                    tid, upstream_name, source_dict = packet._args
                     return not upstream_name and all(source_dict.itervalues())
             # U -> B propagation
             with NEOCluster(partitions=np, replicas=nr-1, storage_count=5,
@@ -513,7 +513,7 @@ class ReplicationTests(NEOThreadedTest):
         """
         def delayAskFetch(conn, packet):
             return isinstance(packet, delayed) and \
-                   packet.decode()[0] == offset and \
+                   packet._args[0] == offset and \
                    conn in s1.getConnectionList(s0)
         def changePartitionTable(orig, ptid, num_replicas, cell_list):
             if (offset, s0.uuid, CellStates.DISCARDED) in cell_list:
@@ -768,7 +768,7 @@ class ReplicationTests(NEOThreadedTest):
         def logReplication(conn, packet):
             if isinstance(packet, (Packets.AskFetchTransactions,
                                    Packets.AskFetchObjects)):
-                ask.append(packet.decode()[2:])
+                ask.append(packet._args[2:])
         def getTIDList():
             return [t.tid for t in c.db().storage.iterator()]
         s0, s1 = cluster.storage_list
@@ -869,7 +869,7 @@ class ReplicationTests(NEOThreadedTest):
                     return True
             elif not isinstance(packet, Packets.AskFetchTransactions):
                 return
-            ask.append(packet.decode())
+            ask.append(packet._args)
         conn, = upstream.master.getConnectionList(backup.master)
         with ConnectionFilter() as f, Patch(replicator.Replicator,
                 _nextPartitionSortKey=lambda orig, self, offset: offset):
@@ -930,11 +930,11 @@ class ReplicationTests(NEOThreadedTest):
             @f.add
             def delayReplicate(conn, packet):
                 if isinstance(packet, Packets.AskFetchTransactions):
-                    trans.append(packet.decode()[2])
+                    trans.append(packet._args[2])
                 elif isinstance(packet, Packets.AskFetchObjects):
                     if obj:
                         return True
-                    obj.append(packet.decode()[2])
+                    obj.append(packet._args[2])
             s2.start()
             self.tic()
             cluster.neoctl.enableStorageList([s2.uuid])
@@ -1021,7 +1021,7 @@ class ReplicationTests(NEOThreadedTest):
         def expected(changed):
             s0 = 1, CellStates.UP_TO_DATE
             s = CellStates.OUT_OF_DATE if changed else CellStates.UP_TO_DATE
-            return changed, 3 * [[s0, (2, s)], [s0, (3, s)]]
+            return changed, 3 * ((s0, (2, s)), (s0, (3, s)))
         for dry_run in True, False:
             self.assertEqual(expected(True),
                 cluster.neoctl.tweakPartitionTable(drop_list, dry_run))

setup.py

@@ -53,7 +53,7 @@ extras_require = {
     'master': [],
     'storage-sqlite': [],
     'storage-mysqldb': ['mysqlclient'],
-    'storage-importer': zodb_require + ['msgpack>=0.5.6', 'setproctitle'],
+    'storage-importer': zodb_require + ['setproctitle'],
 }
 extras_require['tests'] = ['coverage', 'zope.testing', 'psutil>=2',
     'neoppod[%s]' % ', '.join(extras_require)]
@@ -109,6 +109,7 @@ setup(
         ],
     },
     install_requires = [
+        'msgpack>=0.5.6',
         'python-dateutil', # neolog --from
         ],
     extras_require = extras_require,