[jira] [Created] (CAMEL-24919) camel-debezium - the consumer health check has no startup readiness signal

["Andrea Cosentino (Jira)" <ji...@apache.org>]

Andrea Cosentino created CAMEL-24919:
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             Summary: camel-debezium - the consumer health check has no startup readiness signal
                 Key: CAMEL-24919
                 URL: https://issues.apache.org/jira/browse/CAMEL-24919
             Project: Camel
          Issue Type: Improvement
          Components: camel-debezium
            Reporter: Andrea Cosentino


h3. Summary

The Debezium consumer health check added by CAMEL-24889 reports {{UP}} from the moment the route starts,
because it only knows about failures. It has no notion of "the connector is actually consuming yet", so a
readiness probe green-lights the pod before the engine has connected.

h3. Details

{{ScheduledPollConsumerHealthCheck}} can honour {{HealthCheckRegistry.getInitialState()}} - typically
{{DOWN}} - because {{ScheduledPollConsumer.isConsumerReady()}} flips after the first successful poll, so
the check leaves {{DOWN}} on its own. {{DebeziumConsumer}} has no equivalent signal, which is why
CAMEL-24889 deliberately did not adopt {{initialState}}: on the {{failure == null}} path it would pin the
route {{DOWN}} for its whole life.

The embedded engine does offer the signal, through the other callback on the builder:

{code:java}
DebeziumEngine.create(Connect.class)
        .using(...)
        .using(connectorCallback)   // connectorStarted / taskStarted / pollingStarted
        .notifying(this::onEventListener)
        .build();
{code}

{{DebeziumEngine.ConnectorCallback}} has {{connectorStarted()}}, {{taskStarted()}} and
{{pollingStarted()}} (all default methods). Flipping a ready flag from {{pollingStarted()}} - the point at
which {{AsyncEmbeddedEngine}} enters {{POLLING_TASKS}} - would let the health check honour
{{initialState}} the way the scheduled-poll one does, so a route that is still snapshotting or still
connecting reports {{DOWN}} to a readiness probe instead of {{UP}}.

This matters for the connectors whose initial snapshot can take minutes; today the pod is declared ready
long before any change event can be delivered.

h3. Notes

Raised during the review of CAMEL-24889 (https://github.com/apache/camel/pull/26733) by both reviewers and
deliberately left out of that PR, which is scoped to failure detection. Whoever picks this up should keep
the {{failure != null}} branch as it is and only change what the {{failure == null}} branch returns.

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_Reported by Claude Code on behalf of oscerd (Andrea Cosentino)._



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