Add support for latest versions of ZODB (4.4.3 & 5.0.1)

Many patches have been merged upstream :)

A notable change is that lastTransaction() does not ping the master anymore
(but it still causes a connection to the master if the client is disconnected).

ZODB.patch

-Patch to ZODB 4.3.1 for ZODB unit tests.
-See also monkey-patch to Connection.tpc_finish in neo/client/__init__.py
-
-diff --git a/src/ZODB/interfaces.py b/src/ZODB/interfaces.py
-index 44ded35..db5c525 100644
---- a/src/ZODB/interfaces.py
-+++ b/src/ZODB/interfaces.py
-@@ -776,6 +776,10 @@ def tpc_finish(transaction, func = lambda tid: None):
-         called while the storage transaction lock is held.  It takes
-         the new transaction id generated by the transaction.
- 
-+        The return value can be either None or a serial giving new
-+        serial for objects whose ids were passed to previous store calls
-+        in the same transaction, and for which no serial was returned
-+        from either store or tpc_vote for objects passed to store.
-         """
- 
-     def tpc_vote(transaction):
-@@ -794,8 +798,6 @@ def tpc_vote(transaction):
-         The return value can be either None or a sequence of object-id
-         and serial pairs giving new serials for objects who's ids were
-         passed to previous store calls in the same transaction.
--        After the tpc_vote call, new serials must have been returned,
--        either from tpc_vote or store for objects passed to store.
- 
-         A serial returned in a sequence of oid/serial pairs, may be
-         the special value ZODB.ConflictResolution.ResolvedSerial to
-diff --git a/src/ZODB/tests/BasicStorage.py b/src/ZODB/tests/BasicStorage.py
-index e5c0526..0291654 100644
---- a/src/ZODB/tests/BasicStorage.py
-+++ b/src/ZODB/tests/BasicStorage.py
-@@ -69,8 +69,10 @@ def checkSerialIsNoneForInitialRevision(self):
-         r1 = self._storage.store(oid, None, zodb_pickle(MinPO(11)),
-                                        '', txn)
-         r2 = self._storage.tpc_vote(txn)
--        self._storage.tpc_finish(txn)
-+        serial = self._storage.tpc_finish(txn)
-         newrevid = handle_serials(oid, r1, r2)
-+        if newrevid is None and serial is not None:
-+            newrevid = serial
-         data, revid = self._storage.load(oid, '')
-         value = zodb_unpickle(data)
-         eq(value, MinPO(11))
-diff --git a/src/ZODB/tests/MTStorage.py b/src/ZODB/tests/MTStorage.py
-index 4ea139c..347cae3 100644
---- a/src/ZODB/tests/MTStorage.py
-+++ b/src/ZODB/tests/MTStorage.py
-@@ -152,10 +152,12 @@ def dostore(self, i):
-         r2 = self.storage.tpc_vote(t)
-         self.pause()
- 
--        self.storage.tpc_finish(t)
-+        serial = self.storage.tpc_finish(t)
-         self.pause()
- 
-         revid = handle_serials(oid, r1, r2)
-+        if serial is not None and revid is None:
-+            revid = serial
-         self.oids[oid] = revid
- 
- class ExtStorageClientThread(StorageClientThread):
-diff --git a/src/ZODB/tests/RevisionStorage.py b/src/ZODB/tests/RevisionStorage.py
-index 2a5c370..0a0120a 100644
---- a/src/ZODB/tests/RevisionStorage.py
-+++ b/src/ZODB/tests/RevisionStorage.py
-@@ -150,10 +150,12 @@ def helper(tid, revid, x):
-                 # Finish the transaction
-                 r2 = self._storage.tpc_vote(t)
-                 newrevid = handle_serials(oid, r1, r2)
--                self._storage.tpc_finish(t)
-+                serial = self._storage.tpc_finish(t)
-             except:
-                 self._storage.tpc_abort(t)
-                 raise
-+            if serial is not None and newrevid is None:
-+                newrevid = serial
-             return newrevid
-         revid1 = helper(1, None, 1)
-         revid2 = helper(2, revid1, 2)
-diff --git a/src/ZODB/tests/StorageTestBase.py b/src/ZODB/tests/StorageTestBase.py
-index f0a2b72..5305807 100644
---- a/src/ZODB/tests/StorageTestBase.py
-+++ b/src/ZODB/tests/StorageTestBase.py
-@@ -132,7 +132,7 @@ def handle_serials(oid, *args):
- 
-     A helper for function _handle_all_serials().
-     """
--    return handle_all_serials(oid, *args)[oid]
-+    return handle_all_serials(oid, *args).get(oid)
- 
- def import_helper(name):
-     __import__(name)
-@@ -189,7 +189,9 @@ def _dostore(self, oid=None, revid=None, data=None,
-             # Finish the transaction
-             r2 = self._storage.tpc_vote(t)
-             revid = handle_serials(oid, r1, r2)
--            self._storage.tpc_finish(t)
-+            serial = self._storage.tpc_finish(t)
-+            if serial is not None and revid is None:
-+                revid = serial
-         except:
-             self._storage.tpc_abort(t)
-             raise
-@@ -209,8 +211,8 @@ def _undo(self, tid, expected_oids=None, note=None):
-         self._storage.tpc_begin(t)
-         undo_result = self._storage.undo(tid, t)
-         vote_result = self._storage.tpc_vote(t)
--        self._storage.tpc_finish(t)
--        if expected_oids is not None:
-+        serial = self._storage.tpc_finish(t)
-+        if expected_oids is not None and serial is None:
-             oids = list(undo_result[1]) if undo_result else []
-             oids.extend(oid for (oid, _) in vote_result or ())
-             self.assertEqual(len(oids), len(expected_oids), repr(oids))
-diff --git a/src/ZODB/tests/TransactionalUndoStorage.py b/src/ZODB/tests/TransactionalUndoStorage.py
-index 0ee68b2..4dab889 100644
---- a/src/ZODB/tests/TransactionalUndoStorage.py
-+++ b/src/ZODB/tests/TransactionalUndoStorage.py
-@@ -73,6 +73,12 @@ def _transaction_vote(self, trans):
-     def _transaction_newserial(self, oid):
-         return self.__serials[oid]
- 
-+    def _transaction_finish(self, t, oid_list):
-+        tid = self._storage.tpc_finish(t)
-+        if tid is not None:
-+            for oid in oid_list:
-+                self.__serials[oid] = tid
-+
-     def _multi_obj_transaction(self, objs):
-         newrevs = {}
-         t = Transaction()
-@@ -82,7 +88,7 @@ def _multi_obj_transaction(self, objs):
-             self._transaction_store(oid, rev, data, '', t)
-             newrevs[oid] = None
-         self._transaction_vote(t)
--        self._storage.tpc_finish(t)
-+        self._transaction_finish(t, [x[0] for x in objs])
-         for oid in newrevs.keys():
-             newrevs[oid] = self._transaction_newserial(oid)
-         return newrevs
-@@ -219,9 +225,9 @@ def checkTwoObjectUndo(self):
-         self._transaction_store(oid2, revid2, p51, '', t)
-         # Finish the transaction
-         self._transaction_vote(t)
-+        self._transaction_finish(t, [oid1, oid2])
-         revid1 = self._transaction_newserial(oid1)
-         revid2 = self._transaction_newserial(oid2)
--        self._storage.tpc_finish(t)
-         eq(revid1, revid2)
-         # Update those same two objects
-         t = Transaction()
-@@ -231,9 +237,9 @@ def checkTwoObjectUndo(self):
-         self._transaction_store(oid2, revid2, p52, '', t)
-         # Finish the transaction
-         self._transaction_vote(t)
-+        self._transaction_finish(t, [oid1, oid2])
-         revid1 = self._transaction_newserial(oid1)
-         revid2 = self._transaction_newserial(oid2)
--        self._storage.tpc_finish(t)
-         eq(revid1, revid2)
-         # Make sure the objects have the current value
-         data, revid1 = self._storage.load(oid1, '')
-@@ -289,10 +295,11 @@ def checkTwoObjectUndoAtOnce(self):
-         tid1 = info[1]['id']
-         t = Transaction()
-         oids = self._begin_undos_vote(t, tid, tid1)
--        self._storage.tpc_finish(t)
-+        serial = self._storage.tpc_finish(t)
-         # We may get the finalization stuff called an extra time,
-         # depending on the implementation.
--        self.assertEqual(set(oids), set((oid1, oid2)))
-+        if serial is None:
-+            self.assertEqual(set(oids), {oid1, oid2})
-         data, revid1 = self._storage.load(oid1, '')
-         eq(zodb_unpickle(data), MinPO(30))
-         data, revid2 = self._storage.load(oid2, '')
-@@ -326,7 +333,7 @@ def checkTwoObjectUndoAgain(self):
-         self._transaction_store(oid2, revid2, p52, '', t)
-         # Finish the transaction
-         self._transaction_vote(t)
--        self._storage.tpc_finish(t)
-+        self._transaction_finish(t, [oid1, oid2])
-         revid1 = self._transaction_newserial(oid1)
-         revid2 = self._transaction_newserial(oid2)
-         eq(revid1, revid2)
-@@ -346,7 +353,7 @@ def checkTwoObjectUndoAgain(self):
-         self._transaction_store(oid2, revid2, p53, '', t)
-         # Finish the transaction
-         self._transaction_vote(t)
--        self._storage.tpc_finish(t)
-+        self._transaction_finish(t, [oid1, oid2])
-         revid1 = self._transaction_newserial(oid1)
-         revid2 = self._transaction_newserial(oid2)
-         eq(revid1, revid2)
-@@ -358,10 +365,11 @@ def checkTwoObjectUndoAgain(self):
-         tid = info[1]['id']
-         t = Transaction()
-         oids = self._begin_undos_vote(t, tid)
--        self._storage.tpc_finish(t)
--        eq(len(oids), 1)
--        self.assertTrue(oid1 in oids)
--        self.assertTrue(not oid2 in oids)
-+        serial = self._storage.tpc_finish(t)
-+        if serial is None:
-+            eq(len(oids), 1)
-+            self.assertTrue(oid1 in oids)
-+            self.assertTrue(not oid2 in oids)
-         data, revid1 = self._storage.load(oid1, '')
-         eq(zodb_unpickle(data), MinPO(33))
-         data, revid2 = self._storage.load(oid2, '')
-@@ -398,7 +406,7 @@ def checkNotUndoable(self):
-         self._transaction_store(oid1, revid1, p81, '', t)
-         self._transaction_store(oid2, revid2, p91, '', t)
-         self._transaction_vote(t)
--        self._storage.tpc_finish(t)
-+        self._transaction_finish(t, [oid1, oid2])
-         revid1 = self._transaction_newserial(oid1)
-         revid2 = self._transaction_newserial(oid2)
-         eq(revid1, revid2)
-@@ -685,9 +693,9 @@ def undo(i):
-             tid = p64(i + 1)
-             eq(txn.tid, tid)
- 
--            L1 = [(rec.oid, rec.tid, rec.data_txn) for rec in txn]
--            L2 = [(oid, revid, None) for _tid, oid, revid in orig
--                  if _tid == tid]
-+            L1 = {(rec.oid, rec.tid, rec.data_txn) for rec in txn}
-+            L2 = {(oid, revid, None) for _tid, oid, revid in orig
-+                  if _tid == tid}
- 
-             eq(L1, L2)
- 

neo/client/Storage.py

@@ -159,11 +159,8 @@ class Storage(BaseStorage.BaseStorage,
         except NEOStorageNotFoundError:
             raise POSException.POSKeyError(oid)
 
-    def sync(self, force=True):
-        # XXX: sync() is part of IMVCCStorage and we don't want to be called
-        #      from afterCompletion() so it may not be a good place to ping the
-        #      master here. See also monkey-patch in __init__.py
-        self.app.lastTransaction()
+    def sync(self):
+        return self.app.sync()
 
     def copyTransactionsFrom(self, source, verbose=False):
         """ Zope compliant API """
@@ -186,7 +183,7 @@ class Storage(BaseStorage.BaseStorage,
 
     def lastTransaction(self):
         # Used in ZODB unit tests
-        return self.app.lastTransaction()
+        return self.app.last_tid
 
     def _clear_temp(self):
         raise NotImplementedError

neo/client/__init__.py

@@ -12,15 +12,11 @@
 #
 ##############################################################################
 
-import app # set up signal handers early enough to do it in the main thread
-
-if 1:
+def patch():
     from hashlib import md5
     from ZODB.Connection import Connection
 
-    def _check(f, *args):
-        h = md5(f.func_code.co_code).hexdigest()
-        assert h in args, h
+    H = lambda f: md5(f.func_code.co_code).hexdigest()
 
     # Allow serial to be returned as late as tpc_finish
     #
@@ -28,9 +24,7 @@ if 1:
     # removing the requirement to serialise second commit phase (tpc_vote
     # to tpc_finish/tpc_abort).
 
-    _check(Connection.tpc_finish,
-        'ab9b1b8d82c40e5fffa84f7bc4ea3a8b', # Python 2.7
-        )
+    h = H(Connection.tpc_finish)
 
     def tpc_finish(self, transaction):
         """Indicate confirmation that the transaction is done."""
@@ -61,18 +55,27 @@ if 1:
         # </patch>
         self._tpc_cleanup()
 
-    Connection.tpc_finish = tpc_finish
+    global OLD_ZODB
+    OLD_ZODB = h in (
+        'ab9b1b8d82c40e5fffa84f7bc4ea3a8b', # Python 2.7
+        )
+
+    if OLD_ZODB:
+        Connection.tpc_finish = tpc_finish
+    elif hasattr(Connection, '_handle_serial'): # merged upstream ?
+        assert hasattr(Connection, '_warn_about_returned_serial')
 
-    # IStorage implementations usually need to provide a "network barrier",
-    # at least for NEO & ZEO, to make sure we have an up-to-date view of
-    # the storage. It's unclear whether sync() is a good place to do this
-    # because a round-trip to the server introduces latency and we prefer
-    # it's not done when it's not useful.
-    # For example, we know we are up-to-date after a successful commit,
-    # so this should not be done in afterCompletion(), and anyway, we don't
-    # know any legitimate use of DB access outside a transaction.
+    # sync() is used to provide a "network barrier", which is required for
+    # NEO & ZEO to make sure our view of the storage includes all changes done
+    # so far by other clients. But a round-trip to the server introduces
+    # latency so it must not be done when it's not useful. Note also that a
+    # successful commit (which ends with a response from the master) already
+    # acts as a "network barrier".
+    # BBB: What this monkey-patch does has been merged in ZODB5.
+    if not hasattr(Connection, '_flush_invalidations'):
+        return
 
-    _check(Connection.afterCompletion,
+    assert H(Connection.afterCompletion) in (
         'cd3a080b80fd957190ff3bb867149448', # Python 2.7
         )
 
@@ -81,3 +84,7 @@ if 1:
         # PATCH: do not call sync()
         self._flush_invalidations()
     Connection.afterCompletion = afterCompletion
+
+patch()
+
+import app # set up signal handers early enough to do it in the main thread

neo/client/app.py

@@ -24,7 +24,9 @@ from functools import partial
 
 from ZODB.POSException import UndoError, StorageTransactionError, ConflictError
 from ZODB.POSException import ReadConflictError
-from ZODB.ConflictResolution import ResolvedSerial
+from . import OLD_ZODB
+if OLD_ZODB:
+  from ZODB.ConflictResolution import ResolvedSerial
 from persistent.TimeStamp import TimeStamp
 
 from neo.lib import logging
@@ -108,7 +110,6 @@ class Application(ThreadedApplication):
         self._loading_oid = None
         self.new_oid_list = ()
         self.last_oid = '\0' * 8
-        self.last_tid = None
         self.storage_event_handler = storage.StorageEventHandler(self)
         self.storage_bootstrap_handler = storage.StorageBootstrapHandler(self)
         self.storage_handler = storage.StorageAnswersHandler(self)
@@ -136,8 +137,12 @@ class Application(ThreadedApplication):
         self.compress = compress
 
     def __getattr__(self, attr):
-        if attr == 'pt':
-            self._getMasterConnection()
+        if attr in ('last_tid', 'pt'):
+            if self._connecting_to_master_node.locked():
+                if attr == 'last_tid':
+                    return
+            else:
+                self._getMasterConnection()
         return self.__getattribute__(attr)
 
     def log(self):
@@ -603,7 +608,7 @@ class Application(ThreadedApplication):
                 logging.error('tpc_store failed')
                 raise NEOStorageError('tpc_store failed')
             elif oid in resolved_oid_set:
-                append((oid, ResolvedSerial))
+                append((oid, ResolvedSerial) if OLD_ZODB else oid)
         return result
 
     def tpc_vote(self, transaction, tryToResolveConflict):
@@ -950,9 +955,8 @@ class Application(ThreadedApplication):
 
     from .iterator import iterator
 
-    def lastTransaction(self):
-        self._askPrimary(Packets.AskLastTransaction())
-        return self.last_tid
+    def sync(self):
+        self._askPrimary(Packets.Ping())
 
     def pack(self, t):
         tid = TimeStamp(*time.gmtime(t)[:5] + (t % 60, )).raw()

neo/client/handlers/master.py

@@ -99,7 +99,10 @@ class PrimaryNotificationsHandler(MTEventHandler):
             app = self.app
             ltid = packet.decode()[0]
             if app.last_tid != ltid:
-                if app.master_conn is None:
+                # Either we're connecting or we already know the last tid
+                # via invalidations.
+                assert app.master_conn is None, app.master_conn
+                if 1:
                     app._cache_lock_acquire()
                     try:
                         if app.last_tid < ltid:

neo/client/iterator.py

@@ -63,7 +63,7 @@ def iterator(app, start=None, stop=None):
     """NEO transaction iterator"""
     if start is None:
         start = ZERO_TID
-    stop = min(stop or MAX_TID, app.lastTransaction())
+    stop = min(stop or MAX_TID, app.last_tid)
     while 1:
         max_tid, chunk = app.transactionLog(start, stop, CHUNK_LENGTH)
         if not chunk:

neo/lib/handler.py

@@ -226,8 +226,9 @@ class MTEventHandler(EventHandler):
 
     def packetReceived(self, conn, packet, kw={}):
         """Redirect all received packet to dispatcher thread."""
-        if packet.isResponse() and type(packet) is not Packets.Pong:
-            if not self.dispatcher.dispatch(conn, packet.getId(), packet, kw):
+        if packet.isResponse():
+            if not (self.dispatcher.dispatch(conn, packet.getId(), packet, kw)
+                    or type(packet) is Packets.Pong):
                 raise ProtocolError('Unexpected response packet from %r: %r'
                                     % (conn, packet))
         else:

neo/tests/client/testClientApp.py

@@ -38,6 +38,7 @@ class Dispatcher(object):
 
 def _getMasterConnection(self):
     if self.master_conn is None:
+        self.last_tid = None
         self.uuid = 1 + (UUID_NAMESPACES[NodeTypes.CLIENT] << 24)
         self.num_partitions = 10
         self.num_replicas = 1

neo/tests/functional/testClient.py

@@ -335,7 +335,7 @@ class ClientTests(NEOFunctionalTest):
             t3.description = 'desc'
             st3.tpc_begin(t3)
             # retreive the last revision
-            data, serial = st3.load(oid, '')
+            data, serial = st3.load(oid)
             # try to store again, should not be delayed
             st3.store(oid, serial, data, '', t3)
             # the vote should not timeout

neo/tests/threaded/test.py

@@ -632,7 +632,8 @@ class Test(NEOThreadedTest):
             t.begin()
             s0.stop() # force client to ask s1
             self.assertEqual(sorted(c.root()), [1])
-            t0, t1 = c._storage.iterator()
+            self.tic()
+            t0, t1 = c.db().storage.iterator()
         finally:
             cluster.stop()
 
@@ -884,7 +885,7 @@ class Test(NEOThreadedTest):
 
             # Now test cache invalidation during a load from a storage
             ll = LockLock()
-            def _loadFromStorage(orig, *args):
+            def break_after(orig, *args):
                 try:
                     return orig(*args)
                 finally:
@@ -892,7 +893,7 @@ class Test(NEOThreadedTest):
             x2._p_deactivate()
             # Remove last version of x from cache
             cache._remove(cache._oid_dict[x2._p_oid].pop())
-            with ll, Patch(cluster.client, _loadFromStorage=_loadFromStorage):
+            with ll, Patch(cluster.client, _loadFromStorage=break_after):
                 t = self.newThread(x2._p_activate)
                 ll()
                 # At this point, x could not be found the cache and the result
@@ -910,16 +911,18 @@ class Test(NEOThreadedTest):
             self.assertEqual(x2.value, 1)
             self.assertEqual(x1.value, 0)
 
-            # l1 is acquired and l2 is released
+            def invalidations(conn):
+                try:
+                    return conn._storage._invalidations
+                except AttributeError: # BBB: ZODB < 5
+                    return conn._invalidated
+
             # Change x again from 0 to 1, while the checking connection c1
             # is suspended at the beginning of the transaction t1,
             # between Storage.sync() and flush of invalidations.
-            def _flush_invalidations(orig):
-                ll()
-                orig()
             x1._p_deactivate()
             t1.abort()
-            with ll, Patch(c1, _flush_invalidations=_flush_invalidations):
+            with ll, Patch(c1._storage, sync=break_after):
                 t = self.newThread(t1.begin)
                 ll()
                 txn = transaction.Transaction()
@@ -927,10 +930,14 @@ class Test(NEOThreadedTest):
                 client.store(x2._p_oid, tid, y, '', txn)
                 tid = client.tpc_finish(txn, None)
                 client.close()
+                self.assertEqual(invalidations(c1), {x1._p_oid})
             t.join()
-            # A transaction really begins when it acquires the lock to flush
-            # invalidations. The previous lastTransaction() only does a ping
-            # to make sure we have a recent enough view of the DB.
+            # A transaction really begins when it gets the last tid from the
+            # storage, just before flushing invalidations (on ZODB < 5, it's
+            # when it acquires the lock to flush invalidations). The previous
+            # call to sync() only does a ping to make sure we have a recent
+            # enough view of the DB.
+            self.assertFalse(invalidations(c1))
             self.assertEqual(x1.value, 1)
 
         finally:
@@ -969,7 +976,7 @@ class Test(NEOThreadedTest):
             # transaction before the last one, and clearing the cache before
             # reloading x.
             c1._storage.load(x._p_oid)
-            t0, t1, t2 = c1._storage.iterator()
+            t0, t1, t2 = c1.db().storage.iterator()
             self.assertEqual(map(u64, t0.oid_list), [0])
             self.assertEqual(map(u64, t1.oid_list), [0, 1])
             # Check oid 1 is part of transaction metadata.
@@ -1282,6 +1289,7 @@ class Test(NEOThreadedTest):
             t, c = cluster.getTransaction()
             m2c, = cluster.master.getConnectionList(cluster.client)
             cluster.client._cache.clear()
+            c.cacheMinimize()
             with cluster.client.filterConnection(cluster.storage) as c2s:
                 c2s.add(disconnect)
                 # Storages are currently notified of clients that get

neo/tests/threaded/testReplication.py

@@ -404,14 +404,14 @@ class ReplicationTests(NEOThreadedTest):
                 self.tic()
                 s1.stop()
                 cluster.join((s1,))
-            t0, t1, t2 = c._storage.iterator()
+            t0, t1, t2 = c.db().storage.iterator()
             s1.resetNode()
             s1.start()
             self.tic()
             self.assertEqual([], cluster.getOutdatedCells())
             s0.stop()
             cluster.join((s0,))
-            t0, t1, t2 = c._storage.iterator()
+            t0, t1, t2 = c.db().storage.iterator()
         finally:
             cluster.stop()
 

neo/tests/zodb/__init__.py

@@ -43,7 +43,11 @@ class ZODBTestCase(TestCase):
 
     def _tearDown(self, success):
         self._storage.cleanup()
-        self.neo.stop()
+        try:
+            self.neo.stop()
+        except Exception:
+            if success:
+                raise
         del self.neo, self._storage
         super(ZODBTestCase, self)._tearDown(success)
 

neo/tests/zodb/testUndo.py

@@ -28,6 +28,14 @@ class UndoTests(ZODBTestCase, StorageTestBase, TransactionalUndoStorage,
     checkTransactionalUndoAfterPack = expectedFailure()(
         TransactionalUndoStorage.checkTransactionalUndoAfterPack)
 
+for x in ('checkUndoMultipleConflictResolution',
+          'checkUndoMultipleConflictResolutionReversed'):
+    try:
+        setattr(UndoTests, x,
+            expectedFailure(KeyError)(getattr(TransactionalUndoStorage, x)))
+    except AttributeError:
+        pass
+
 if __name__ == "__main__":
     suite = unittest.makeSuite(UndoTests, 'check')
     unittest.main(defaultTest='suite')