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authordrebs <drebs@leap.se>2012-12-06 11:07:53 -0200
committerdrebs <drebs@leap.se>2012-12-06 11:07:53 -0200
commit30c9ec2a115b157e608e97c9b8449fc9c753b60f (patch)
treee36dfed8ef7cd0beae446909eef22b662cb92554 /u1db/vectorclock.py
parent08fd87714f503c551b8e2dc29e55ae4497b42759 (diff)
Remove u1db and swiftclient dirs and refactor.
Diffstat (limited to 'u1db/vectorclock.py')
-rw-r--r--u1db/vectorclock.py89
1 files changed, 0 insertions, 89 deletions
diff --git a/u1db/vectorclock.py b/u1db/vectorclock.py
deleted file mode 100644
index 42bceaa8..00000000
--- a/u1db/vectorclock.py
+++ /dev/null
@@ -1,89 +0,0 @@
-# Copyright 2011 Canonical Ltd.
-#
-# This file is part of u1db.
-#
-# u1db is free software: you can redistribute it and/or modify
-# it under the terms of the GNU Lesser General Public License version 3
-# as published by the Free Software Foundation.
-#
-# u1db is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-# GNU Lesser General Public License for more details.
-#
-# You should have received a copy of the GNU Lesser General Public License
-# along with u1db. If not, see <http://www.gnu.org/licenses/>.
-
-"""VectorClockRev helper class."""
-
-
-class VectorClockRev(object):
- """Track vector clocks for multiple replica ids.
-
- This allows simple comparison to determine if one VectorClockRev is
- newer/older/in-conflict-with another VectorClockRev without having to
- examine history. Every replica has a strictly increasing revision. When
- creating a new revision, they include all revisions for all other replicas
- which the new revision dominates, and increment their own revision to
- something greater than the current value.
- """
-
- def __init__(self, value):
- self._values = self._expand(value)
-
- def __repr__(self):
- s = self.as_str()
- return '%s(%s)' % (self.__class__.__name__, s)
-
- def as_str(self):
- s = '|'.join(['%s:%d' % (m, r) for m, r
- in sorted(self._values.items())])
- return s
-
- def _expand(self, value):
- result = {}
- if value is None:
- return result
- for replica_info in value.split('|'):
- replica_uid, counter = replica_info.split(':')
- counter = int(counter)
- result[replica_uid] = counter
- return result
-
- def is_newer(self, other):
- """Is this VectorClockRev strictly newer than other.
- """
- if not self._values:
- return False
- if not other._values:
- return True
- this_is_newer = False
- other_expand = dict(other._values)
- for key, value in self._values.iteritems():
- if key in other_expand:
- other_value = other_expand.pop(key)
- if other_value > value:
- return False
- elif other_value < value:
- this_is_newer = True
- else:
- this_is_newer = True
- if other_expand:
- return False
- return this_is_newer
-
- def increment(self, replica_uid):
- """Increase the 'replica_uid' section of this vector clock.
-
- :return: A string representing the new vector clock value
- """
- self._values[replica_uid] = self._values.get(replica_uid, 0) + 1
-
- def maximize(self, other_vcr):
- for replica_uid, counter in other_vcr._values.iteritems():
- if replica_uid not in self._values:
- self._values[replica_uid] = counter
- else:
- this_counter = self._values[replica_uid]
- if this_counter < counter:
- self._values[replica_uid] = counter