In and only in RelWithDebInfo mode the access of the maybe_unused
variable results in segfaults, this change is making sure that does no
happen ever if the maybe_unused variable is nullopt without changing the
overall logic.
Implement constant time label and edge type retrieval
Memgraph now includes two additional queries designed to retrieve
information about the schema of the stored graphs. The SHOW
NODE_LABELS INFO and SHOW EDGE_TYPES INFO queries return
the list of vertex-labels and edge-types that are currently present or at
some point were present in the database respectively. In order for
these queries to work, the flag --storage-enable-schema-metadata has
to be set to True on startup.
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>
Single (instance level) connection to a replica (messages from all databases get multiplexed through it)
ReplicationClient split in two: ReplicationClient and ReplicationStorageClient
New ReplicationClient, moved under replication, handles the raw connection, owned by MainRoleData
ReplicationStorageClient handles the storage <-> replica state machine and holds to a stream
Removed epoch and storage from *Clients
rpc::Stream proactively aborts on error and sets itself to a defunct state
Removed HandleRpcFailure, instead we simply log the error and let the FrequentCheck handle re-connection
replica_state is now a synced variable
ReplicaStorageClient state machine bugfixes
Single FrequentCheck that goes through DBMS
Moved ReplicationState under DbmsHandler
Moved some replication startup logic under the DbmsHandler's constructor
Removed InMemoryReplicationClient
CreateReplicationClient has been removed from Storage
Simplified GetRecoverySteps and made safer
---------
Co-authored-by: Gareth Lloyd <gareth.lloyd@memgraph.io>
