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ASF GitHub Bot commented on FLINK-4123: --------------------------------------- Github user tillrohrmann commented on the issue: https://github.com/apache/flink/pull/2183 If our components are not testable, then this is good indicator that we can still improve our design. But actually I think that it should be doable in this case. Can't we mock the `Session` such that it stores all `ResultSetFutures`. We can then manually let one of the futures fail and let the other complete normally. That way, we could test the newly implemented behaviour. > CassandraWriteAheadSink can hang on cassandra failure > ----------------------------------------------------- > > Key: FLINK-4123 > URL: https://issues.apache.org/jira/browse/FLINK-4123 > Project: Flink > Issue Type: Bug > Components: Streaming Connectors > Affects Versions: 1.1.0 > Reporter: Chesnay Schepler > Assignee: Chesnay Schepler > Priority: Blocker > Fix For: 1.1.0 > > > The CassandraWriteAheadSink verifies that all writes send to cassandra have > been applied by counting how many were sent and how many callbacks were > activated. Once all writes were sent the sink enters into a loop that is only > exited once both counts are equal. > Thus, should cassandra crash after all writes were sent, without having > acknowledged all writes, the sink will deadlock in the loop. -- This message was sent by Atlassian JIRA (v6.3.4#6332)