shashank created CAMEL-25278:
--------------------------------
Summary: camel-cometd - a stopped consumer stays subscribed to its
channel (each message is processed twice after a route restart), and the
extensions and server listeners are added again for every producer and consumer
Key: CAMEL-25278
URL: https://issues.apache.org/jira/browse/CAMEL-25278
Project: Camel
Issue Type: Bug
Components: camel-cometd
Reporter: shashank
The producers and consumers of a host and port share one CometD server
({{CometdComponent.connect}} / {{disconnect}} with a reference count); the
server is only stopped with the last of them.
h3. 1. A stopped consumer keeps listening to its channel
{{CometdConsumer.doStart}} creates a {{ConsumerService}}
({{AbstractService.addService(channel, "push")}}, a listener on the channel)
and {{doStop}} only calls {{endpoint.disconnect(this)}}: the listener stays on
the channel. When the server outlives the consumer (a producer, or a consumer
of another channel, on the same host and port) the old listener keeps calling
the processor of the route. After a restart of the route there are two
listeners, and every message is processed twice (three times after two
restarts, ...).
h3. 2. Extensions and server listeners are added for every producer and consumer
{{CometdComponent.connect}} adds the configured {{extensions}} and
{{serverListeners}} to the {{BayeuxServerImpl}} on every call, also when the
server already exists. {{BayeuxServerImpl}} keeps them in a
{{CopyOnWriteArrayList}}, so with a producer and a consumer on the same host
and port each extension and listener is called twice per message or session
(and once more after each restart). An extension that changes or counts
messages (or does authentication work) runs several times.
h3. Reproduction
{{CometdConsumerRestartTest}} (a producer route and a consumer route on the
same host and port, in process):
* stop and start the consumer route, send one message: main delivers it twice
({{mock://test Received message count. Expected: <1> but was: <2>}});
* a {{SessionListener}} registered with {{addServerListener}} is called twice
for one new session ({{expected: <1> but was: <2>}});
* control: a stopped consumer route does not receive (passes on main too: the
stopped route refuses the exchange).
h3. Proposed fix
* {{CometdConsumer.doStop}}: remove the service from the channel and disconnect
its local session.
* {{CometdComponent.connect}}: set the security policy and add the extensions
and server listeners only when the server is created.
With the fix the camel-cometd tests pass (26).
Affected: 4.14.x, 4.18.x and main (same code).
Duplicate check (2026-10-02): JIRA component camel-cometd / text "cometd" (87
issues, mostly camel-salesforce): none about consumer stop or duplicate
extensions (CAMEL-23507 header filter, CAMEL-12267 transport properties).
GitHub pull requests "cometd consumer", "cometd extension": none; open #22358
(getOut cleanup) touches another line of {{CometdConsumer}}.
_Filed with Claude Code on behalf of allthingssecurity._
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
