Camel-Netty-* connectors are not working

[oscerd]

[2021-01-27 17:19:21,237] INFO Apache Camel 3.7.0 (camel-1) is shutting down (org.apache.camel.impl.engine.AbstractCamelContext:2907)
[2021-01-27 17:19:21,245] INFO Apache Camel 3.7.0 (camel-1) uptime 78ms (org.apache.camel.impl.engine.AbstractCamelContext:3028)
[2021-01-27 17:19:21,245] INFO Apache Camel 3.7.0 (camel-1) is shutdown in 8ms (org.apache.camel.impl.engine.AbstractCamelContext:3029)
[2021-01-27 17:19:21,246] INFO WorkerSourceTask{id=CamelNettySourceConnector-0} Committing offsets (org.apache.kafka.connect.runtime.WorkerSourceTask:416)
[2021-01-27 17:19:21,246] INFO WorkerSourceTask{id=CamelNettySourceConnector-0} flushing 0 outstanding messages for offset commit (org.apache.kafka.connect.runtime.WorkerSourceTask:433)
[2021-01-27 17:19:21,246] ERROR WorkerSourceTask{id=CamelNettySourceConnector-0} Task threw an uncaught and unrecoverable exception (org.apache.kafka.connect.runtime.WorkerTask:179)
org.apache.kafka.connect.errors.ConnectException: Failed to create and start Camel context
	at org.apache.camel.kafkaconnector.CamelSourceTask.start(CamelSourceTask.java:144)
	at org.apache.kafka.connect.runtime.WorkerSourceTask.execute(WorkerSourceTask.java:208)
	at org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:177)
	at org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:227)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.IllegalArgumentException: hostname can't be null
	at java.net.InetSocketAddress.checkHost(InetSocketAddress.java:149)
	at java.net.InetSocketAddress.<init>(InetSocketAddress.java:216)
	at org.apache.camel.component.netty.SingleTCPNettyServerBootstrapFactory.startServerBootstrap(SingleTCPNettyServerBootstrapFactory.java:184)
	at org.apache.camel.component.netty.SingleTCPNettyServerBootstrapFactory.doStart(SingleTCPNettyServerBootstrapFactory.java:113)
	at org.apache.camel.support.service.BaseService.start(BaseService.java:115)
	at org.apache.camel.support.service.ServiceHelper.startService(ServiceHelper.java:84)
	at org.apache.camel.component.netty.NettyConsumer.doStart(NettyConsumer.java:75)
	at org.apache.camel.support.service.BaseService.start(BaseService.java:115)
	at org.apache.camel.impl.engine.AbstractCamelContext.startService(AbstractCamelContext.java:3108)
	at org.apache.camel.impl.engine.InternalRouteStartupManager.doStartOrResumeRouteConsumers(InternalRouteStartupManager.java:362)
	at org.apache.camel.impl.engine.InternalRouteStartupManager.doStartRouteConsumers(InternalRouteStartupManager.java:282)
	at org.apache.camel.impl.engine.InternalRouteStartupManager.safelyStartRouteServices(InternalRouteStartupManager.java:181)
	at org.apache.camel.impl.engine.InternalRouteStartupManager.doStartOrResumeRoutes(InternalRouteStartupManager.java:115)
	at org.apache.camel.impl.engine.AbstractCamelContext.doStartCamel(AbstractCamelContext.java:2889)
	at org.apache.camel.impl.engine.AbstractCamelContext.doStartContext(AbstractCamelContext.java:2702)
	at org.apache.camel.impl.engine.AbstractCamelContext.doStart(AbstractCamelContext.java:2665)
	at org.apache.camel.support.service.BaseService.start(BaseService.java:115)
	at org.apache.camel.impl.engine.AbstractCamelContext.start(AbstractCamelContext.java:2431)
	at org.apache.camel.main.SimpleMain.doStart(SimpleMain.java:43)
	at org.apache.camel.support.service.BaseService.start(BaseService.java:115)
	at org.apache.camel.kafkaconnector.CamelSourceTask.start(CamelSourceTask.java:141)
	... 8 more

with this configuration

name=CamelNettySourceConnector
connector.class=org.apache.camel.kafkaconnector.netty.CamelNettySourceConnector
tasks.max=1

# use the kafka converters that better suit your needs, these are just defaults:
key.converter=org.apache.kafka.connect.storage.StringConverter
value.converter=org.apache.kafka.connect.storage.StringConverter

# comma separated topics to send messages into
topics=mytopic

# mandatory properties (for a complete properties list see the connector documentation):

# The hostname. For the consumer the hostname is localhost or 0.0.0.0. For the producer the hostname is the remote host to connect to
camel.source.path.host=localhost
# The host port number
camel.source.path.port=8182
# The protocol to use which can be tcp or udp. One of: [tcp] [udp]
camel.source.path.protocol=tcp

It seems that the BootstrapFactory fails at finding the host. But it's defined.

[valdar]

Possibly related to #665

[oscerd]

Yes, it's the same problem.

[oscerd]

With a plain camel.source.url it works

name=CamelNettySourceConnector
connector.class=org.apache.camel.kafkaconnector.netty.CamelNettySourceConnector
tasks.max=1

# use the kafka converters that better suit your needs, these are just defaults:
key.converter=org.apache.kafka.connect.storage.StringConverter
value.converter=org.apache.kafka.connect.storage.StringConverter

# comma separated topics to send messages into
topics=mytopic

# mandatory properties (for a complete properties list see the connector documentation):

# The hostname. For the consumer the hostname is localhost or 0.0.0.0. For the producer the hostname is the remote host to connect to
# The protocol to use which can be tcp or udp. One of: [tcp] [udp]
camel.source.url=netty:tcp://0.0.0.0:8182

[tadayosi]

I'll work on #1036 next, so let's see if I can catch this issue there, too.

[tadayosi]

I think I figured out what's causing the issue and #665. It turns out it's potentially broader than just a couple of connectors. It's an issue in how the EndpointUriFactorys map properties to the endpoint URL, which is used in the TaskHelper. For Netty, the endpoint syntax is defined as netty:protocol:host:port as follows:
https://github.com/apache/camel/blob/master/components/camel-netty/src/generated/java/org/apache/camel/component/netty/NettyEndpointUriFactory.java#L18
https://github.com/apache/camel/blob/master/components/camel-netty/src/main/java/org/apache/camel/component/netty/NettyEndpoint.java#L43
but it really should be netty:protocol://host:port. So I think Camel upstream needs to be fixed first.

For the time being, a workaround would be to use camel.source.path.host=//localhost or camel.sink.path.host=//localhost.

But I suspect there are potentially more components/connectors that have the same issue. I wonder if it's easy for the Camel core side to generate some basic tests against the EndpointUriFactories that check its url syntax with the mandatory properties (like protocol, host, and port, etc.).

[tadayosi]

https://issues.apache.org/jira/browse/CAMEL-16280

[orpiske]

I think

I think I figured out what's causing the issue and #665. It turns out it's potentially broader than just a couple of connectors. It's an issue in how the EndpointUriFactorys map properties to the endpoint URL, which is used in the TaskHelper. For Netty, the endpoint syntax is defined as netty:protocol:host:port as follows:
https://github.com/apache/camel/blob/master/components/camel-netty/src/generated/java/org/apache/camel/component/netty/NettyEndpointUriFactory.java#L18
https://github.com/apache/camel/blob/master/components/camel-netty/src/main/java/org/apache/camel/component/netty/NettyEndpoint.java#L43
but it really should be netty:protocol://host:port. So I think Camel upstream needs to be fixed first.

For the time being, a workaround would be to use camel.source.path.host=//localhost or camel.sink.path.host=//localhost.

But I suspect there are potentially more components/connectors that have the same issue. I wonder if it's easy for the Camel core side to generate some basic tests against the EndpointUriFactories that check its url syntax with the mandatory properties (like protocol, host, and port, etc.).

I think this might also be the related to #629.

[orpiske]

I mean: the same type of issue. Not netty specifically.

[valdar]

Thanks @tadayosi for looking into this!

Please signal when the camel issue is fixed so we can review this one in the next release.

[valdar]

AA! I see that will be in camel 3.9.0 awesome!

[valdar]

Do we have a unit/itest for this?

[valdar]

related to #1077