memgraph/tests/e2e/replication/edge_delete.py
Gareth Andrew Lloyd 14f92b4a0f
Bugfix: correct replication handler (#1540)
Fixes root cause of a cascade of failures in replication code:
- Replica handling of deleting an edge is now corrected. Now tolerant of multiple edges of the same relationship type.
- Improved robustness: correct exception handling around failed stream of current WAL file. This now means a REPLICA failure will no longer prevent transactions on MAIN from performing WAL writes.
- Slightly better diagnostic messages, not user friendly but helps get developer to correct root cause quicker.
- Proactively remove vertex+edges during Abort rather than defer to GC to do that work, this included fixing constraints and indexes to be safe.


Co-authored-by: Andreja Tonev <andreja.tonev@memgraph.io>
2023-12-01 12:38:48 +00:00

57 lines
1.9 KiB
Python
Executable File

# Copyright 2022 Memgraph Ltd.
#
# Use of this software is governed by the Business Source License
# included in the file licenses/BSL.txt; by using this file, you agree to be bound by the terms of the Business Source
# License, and you may not use this file except in compliance with the Business Source License.
#
# As of the Change Date specified in that file, in accordance with
# the Business Source License, use of this software will be governed
# by the Apache License, Version 2.0, included in the file
# licenses/APL.txt.
import sys
import time
import pytest
from common import execute_and_fetch_all
from mg_utils import mg_sleep_and_assert
# BUGFIX: for issue https://github.com/memgraph/memgraph/issues/1515
def test_replication_handles_delete_when_multiple_edges_of_same_type(connection):
# Goal is to check the timestamp are correctly computed from the information we get from replicas.
# 0/ Check original state of replicas.
# 1/ Add nodes and edges to MAIN, then delete the edges.
# 2/ Check state of replicas.
# 0/
conn = connection(7687, "main")
conn.autocommit = True
cursor = conn.cursor()
actual_data = set(execute_and_fetch_all(cursor, "SHOW REPLICAS;"))
expected_data = {
("replica_1", "127.0.0.1:10001", "sync", 0, 0, "ready"),
("replica_2", "127.0.0.1:10002", "async", 0, 0, "ready"),
}
assert actual_data == expected_data
# 1/
execute_and_fetch_all(cursor, "CREATE (a)-[r:X]->(b) CREATE (a)-[:X]->(b) DELETE r;")
# 2/
expected_data = {
("replica_1", "127.0.0.1:10001", "sync", 2, 0, "ready"),
("replica_2", "127.0.0.1:10002", "async", 2, 0, "ready"),
}
def retrieve_data():
return set(execute_and_fetch_all(cursor, "SHOW REPLICAS;"))
actual_data = mg_sleep_and_assert(expected_data, retrieve_data)
assert actual_data == expected_data
if __name__ == "__main__":
sys.exit(pytest.main([__file__, "-rA"]))