Move error handling logic to the connection layer #322
Conversation
It was previously spread between `RoutingSession`, `RoutingTransaction` and `RoutingStatementResult` and they all did the same thing when connection errors happened. This commit introduces `RoutingPooledConnection` that handles errors for routing driver by removing entries from the routing table and purging connection pool for failed address.
| // In the future, we might be able to move this logic to the server. | ||
| switch ( accessMode ) | ||
| { | ||
| case READ: |
There was a problem hiding this comment.
We actually do not need this READ/WRITE mode as the error itself already self explained:
Neo.ClientError.Cluster.NotALeader -> server at xx no longer accepts writes
Neo.ClientError.General.ForbiddenOnReadOnlyDatabase -> Write queries cannot be performed in READ access mode
So we could totally remove access mode from this class
There was a problem hiding this comment.
It is possible to get NotALeader when trying to write in a read session with connection towards follower and ForbiddenOnReadOnlyDatabase when connection is towards read replica. So it looks like we still need this switch on the access mode.
|
|
||
| public interface PooledConnection extends Connection | ||
| { | ||
| long lastUsedTimestamp(); |
There was a problem hiding this comment.
We should also move
onError
hasUnrecoverableErrors
from Connection to PooledConnection
|
|
||
| private static boolean isFailureToWrite( ClientException e ) | ||
| { | ||
| return e.code().equals( "Neo.ClientError.Cluster.NotALeader" ) || |
There was a problem hiding this comment.
Warning: you might get ClientException without code field at this stage :)
Methods `#onError()` and `#hasUnrecoverableErrors()` are only useful in pooled connection and their implementations threw exceptions in regular connection. This commit moves them to `PooledConnection` interface.
|
@zhenlineo comments should be addressed now |
2 participants
It was previously spread between
RoutingSession,RoutingTransactionandRoutingStatementResultand they all did the same thing when connection errors happened.This PR introduces
RoutingPooledConnectionthat handles errors for routing driver by removing entries from the routing table and purging connection pool for failed address.