def postgresql_load_current(self, cursor, oid):
"""Returns the current pickle and integer tid for an object.
oid is an integer. Returns (None, None) if object does not exist.
"""
if self.keep_history:
stmt = """
SELECT encode(state, 'base64'), tid
FROM current_object
JOIN object_state USING(zoid, tid)
WHERE zoid = %s
"""
else:
stmt = """
SELECT encode(state, 'base64'), tid
FROM object_state
WHERE zoid = %s
"""
cursor.execute(stmt, (oid,))
if cursor.rowcount:
assert cursor.rowcount == 1
state64, tid = cursor.fetchone()
if state64 is not None:
state = decodestring(state64)
else:
# This object's creation has been undone
state = None
return state, tid
else:
return None, None
def postgresql_load_before(self, cursor, oid, tid):
"""Returns the pickle and tid of an object before transaction tid.
Returns (None, None) if no earlier state exists.
"""
stmt = """
SELECT encode(state, 'base64'), tid
FROM object_state
WHERE zoid = %s
AND tid < %s
ORDER BY tid DESC
LIMIT 1
"""
cursor.execute(stmt, (oid, tid))
if cursor.rowcount:
assert cursor.rowcount == 1
state64, tid = cursor.fetchone()
if state64 is not None:
state = decodestring(state64)
else:
# The object's creation has been undone
state = None
return state, tid
else:
return None, None
def postgresql_detect_conflict(self, cursor):
"""Find one conflict in the data about to be committed.
If there is a conflict, returns (oid, prev_tid, attempted_prev_tid,
attempted_data). If there is no conflict, returns None.
"""
if self.keep_history:
stmt = """
SELECT temp_store.zoid, current_object.tid, temp_store.prev_tid,
encode(temp_store.state, 'base64')
FROM temp_store
JOIN current_object ON (temp_store.zoid = current_object.zoid)
WHERE temp_store.prev_tid != current_object.tid
LIMIT 1
"""
else:
stmt = """
SELECT temp_store.zoid, object_state.tid, temp_store.prev_tid,
encode(temp_store.state, 'base64')
FROM temp_store
JOIN object_state ON (temp_store.zoid = object_state.zoid)
WHERE temp_store.prev_tid != object_state.tid
LIMIT 1
"""
cursor.execute(stmt)
if cursor.rowcount:
oid, prev_tid, attempted_prev_tid, data = cursor.fetchone()
return oid, prev_tid, attempted_prev_tid, decodestring(data)
return None
def postgresql_load_current(self, cursor, oid):
"""Returns the current pickle and integer tid for an object.
oid is an integer. Returns (None, None) if object does not exist.
"""
if self.keep_history:
stmt = """
SELECT encode(state, 'base64'), tid
FROM current_object
JOIN object_state USING(zoid, tid)
WHERE zoid = %s
"""
else:
stmt = """
SELECT encode(state, 'base64'), tid
FROM object_state
WHERE zoid = %s
"""
cursor.execute(stmt, (oid, ))
if cursor.rowcount:
assert cursor.rowcount == 1
state64, tid = cursor.fetchone()
if state64 is not None:
state = decodestring(state64)
else:
# This object's creation has been undone
state = None
return state, tid
else:
return None, None
def postgresql_detect_conflict(self, cursor):
"""Find one conflict in the data about to be committed.
If there is a conflict, returns (oid, prev_tid, attempted_prev_tid,
attempted_data). If there is no conflict, returns None.
"""
if self.keep_history:
stmt = """
SELECT temp_store.zoid, current_object.tid, temp_store.prev_tid,
encode(temp_store.state, 'base64')
FROM temp_store
JOIN current_object ON (temp_store.zoid = current_object.zoid)
WHERE temp_store.prev_tid != current_object.tid
LIMIT 1
"""
else:
stmt = """
SELECT temp_store.zoid, object_state.tid, temp_store.prev_tid,
encode(temp_store.state, 'base64')
FROM temp_store
JOIN object_state ON (temp_store.zoid = object_state.zoid)
WHERE temp_store.prev_tid != object_state.tid
LIMIT 1
"""
cursor.execute(stmt)
if cursor.rowcount:
oid, prev_tid, attempted_prev_tid, data = cursor.fetchone()
return oid, prev_tid, attempted_prev_tid, decodestring(data)
return None
def postgresql_load_before(self, cursor, oid, tid):
"""Returns the pickle and tid of an object before transaction tid.
Returns (None, None) if no earlier state exists.
"""
stmt = """
SELECT encode(state, 'base64'), tid
FROM object_state
WHERE zoid = %s
AND tid < %s
ORDER BY tid DESC
LIMIT 1
"""
cursor.execute(stmt, (oid, tid))
if cursor.rowcount:
assert cursor.rowcount == 1
state64, tid = cursor.fetchone()
if state64 is not None:
state = decodestring(state64)
else:
# The object's creation has been undone
state = None
return state, tid
else:
return None, None
def decode_bytes_param(value, use_base64):
if not isinstance(value, bytes):
value = value.encode('latin1')
if use_base64:
value = decodestring(value)
return value
def decode_bytes_param(value, use_base64):
if not isinstance(value, bytes):
value = value.encode('latin1')
if use_base64:
value = decodestring(value)
return value
def postgresql_load_revision(self, cursor, oid, tid):
"""Returns the pickle for an object on a particular transaction.
Returns None if no such state exists.
"""
stmt = """
SELECT encode(state, 'base64')
FROM object_state
WHERE zoid = %s
AND tid = %s
"""
cursor.execute(stmt, (oid, tid))
if cursor.rowcount:
assert cursor.rowcount == 1
(state64,) = cursor.fetchone()
if state64 is not None:
return decodestring(state64)
return None
def postgresql_load_revision(self, cursor, oid, tid):
"""Returns the pickle for an object on a particular transaction.
Returns None if no such state exists.
"""
stmt = """
SELECT encode(state, 'base64')
FROM object_state
WHERE zoid = %s
AND tid = %s
"""
cursor.execute(stmt, (oid, tid))
if cursor.rowcount:
assert cursor.rowcount == 1
(state64, ) = cursor.fetchone()
if state64 is not None:
return decodestring(state64)
return None
def decode_bytes_param(value, use_base64):
value = str(value)
if use_base64:
value = decodestring(value)
return value
def decode_bytes_param(value, use_base64):
value = str(value)
if use_base64:
value = decodestring(value)
return value
