[Zodb-checkins] CVS: ZODB4/BDBStorage - BDBFullStorage.py:2.3
Mon, 16 Dec 2002 16:00:13 -0500
Update of /cvs-repository/ZODB4/BDBStorage
In directory cvs.zope.org:/tmp/cvs-serv6050
_dostore(): Fix the VersionLockError to the constructor interface used
_dorestore(): Forward porting fix from zodb3, namely that if prev_txn
points to a non-existant transaction, just ignore it.
=== ZODB4/BDBStorage/BDBFullStorage.py 2.2 => 2.3 ===
--- ZODB4/BDBStorage/BDBFullStorage.py:2.2 Fri Dec 6 15:41:30 2002
+++ ZODB4/BDBStorage/BDBFullStorage.py Mon Dec 16 16:00:12 2002
@@ -498,11 +498,11 @@
nvrevid = orevid
elif ovid <> vid:
+ # Figure out the version name for the exception
+ oversion = self._versions[ovid]
# We're trying to make a change on a version that's different
# than the version the current revision is on. Nuh uh.
- raise POSException.VersionLockError(
- 'version mismatch for object %s (was: %s, got: %s)' %
- tuple(map(u64, (oid, ovid, vid))))
+ raise POSException.VersionLockError(oid, oversion)
# We're making another change to this object on this version.
# The non-version revid is the same as for the previous
@@ -562,20 +562,28 @@
# Get the metadata for the previous revision, so that we can dig out
# the non-version revid, but only if there /is/ a previous revision
if prevrevid <> ZERO:
- ovid, onvrevid = unpack(
- '>8s8s', self._metadata[oid+prevrevid][:16])
- if ovid == ZERO:
- # The last revision of this object was made on the
- # non-version, we don't care where the current change is
- # made. But if we're storing this change on a version then
- # the non-version revid will be the previous revid
- if version:
- nvrevid = prevrevid
+ ovid, onvrevid = unpack(
+ '>8s8s', self._metadata[oid+prevrevid][:16])
+ except KeyError:
+ # prev_txn is just a hint. If the transaction it points to
+ # does not exist, perhaps because it's been packed away, just
+ # ignore it. Also, check to see if the data matches. If
+ # not...
+ prevrevid = ZERO
- # We're making another change to this object on this version.
- # The non-version revid is the same as for the previous
- # revision of the object.
- nvrevid = onvrevid
+ if ovid == ZERO:
+ # The last revision of this object was made on the
+ # non-version, we don't care where the current change is
+ # made. But if we're storing this change on a version
+ # then the non-version revid will be the previous revid
+ if version:
+ nvrevid = prevrevid
+ # We're making another change to this object on this
+ # version. The non-version revid is the same as for the
+ # previous revision of the object.
+ nvrevid = onvrevid
# Check for George Bailey Events
if data is None:
lrevid = DNE
@@ -616,8 +624,14 @@
# - data can be None, which indicates a George Bailey object
# (i.e. one who's creation has been transactionally undone).
- # If prev_txn is not None, it should contain the same data as
- # the argument data. If it does, write a backpointer to it.
+ # prev_txn is a backpointer. In the original database, it's possible
+ # that the data was actually living in a previous transaction. This
+ # can happen for transactional undo and other operations, and is used
+ # as a space saving optimization. Under some circumstances the
+ # prev_txn may not actually exist in the target database (i.e. self)
+ # for example, if it's been packed away. In that case, the prev_txn
+ # should be considered just a hint, and is ignored if the transaction
+ # doesn't exist.
if transaction is not self._transaction:
raise POSException.StorageTransactionError(self, transaction)