def load(self, oid, version):
serial = self.__serial
S = self.__base
filter= lambda t, serial= serial: t['tid'] <= serial # this might need to become a picklable object, once ZEO supports 'filter'.
if _hasSmartHistory(S):
ts= S.history(oid, None, 1, filter= filter,)
else:
ts = HistoryFetcher(S, oid, None, last=1, filter=filter).next()
if not ts: raise POSKeyError((oid, serial))
oserial = ts[0]['tid']
return S.loadSerial(oid, oserial), oserial
def __init__(self, storage, oid, version=None, first=0, last=None, filter=None):
'''prepare fetching historical records for *oid* in *version*.
Tries to find records satisfying *filter*. Records *first*
through *last* are returned.
'''
S = storage
history = S.history
if _hasSmartHistory(S): self._smartHistory = history
else: self._getRawHistory = history
self._oid = oid
self._version = version
self._first = first
self._last = last
self._filter = _Filter(filter)
