Just for the record, I have tried adding "bridgeErrorHandler=true" to the
route . This does not help and Camel still tries to connect to the
non-existing Kafka. Final route looks like this:
from("kafka:{{consumer.topic}}?bridgeErrorHandler=true&brokers={{kafka.host}}:{{kafka.port}}"
+ "&maxPollRecords={{consumer.maxPollRecords}}"
+ "&consumersCount={{consumer.consumersCount}}"
+ "&seekTo={{consumer.seekTo}}"
+ "&groupId={{consumer.group}}")
I was expecting an exception to be thrown but this does not happen. This is
based on https://github.com/apache/camel/blob/master/examples/camel-e
xample-kafka/src/main/java/org/apache/camel/example/kafka/
MessageConsumerClient.java with just an additional
"bridgeErrorHandler=true" added to the route.
2017-12-03 14:54 GMT+02:00 Yacov Schondorf <[email protected]>:
> No solution by Camel for detecting connection errors? I gave a very clear
> reproducible scenario...
>
> 2017-11-28 11:44 GMT+02:00 Yacov Schondorf <[email protected]>:
>
>> But this is exactly my point - there is no stack trace! I want there to
>> be a stacktrace so that I could catch it using the regular error handler.
>> This is the purpose of the call to endpoint1.setBridgeErrorHandler(true);
>> However, the call does not work, no trace is printed and the polling
>> continues. Here is the complete code based on https://github.com/apache/c
>> amel/blob/master/examples/camel-example-kafka/src/main/java/
>> org/apache/camel/example/kafka/MessageConsumerClient.java with my
>> addition between the *// change start *and *// change end *blocks:
>>
>> package org.apache.camel.example.kafka;
>>
>> import org.apache.camel.CamelContext;
>> import org.apache.camel.Endpoint;
>> import org.apache.camel.Exchange;
>> import org.apache.camel.Processor;
>> import org.apache.camel.builder.RouteBuilder;
>> import org.apache.camel.component.kafka.KafkaEndpoint;
>> import org.apache.camel.component.properties.PropertiesComponent;
>> import org.apache.camel.impl.DefaultCamelContext;
>> import org.apache.camel.impl.DefaultEndpoint;
>> import org.slf4j.Logger;
>> import org.slf4j.LoggerFactory;
>>
>> import java.util.Collection;
>> import java.util.HashMap;
>> import java.util.Iterator;
>>
>> public final class MessageConsumerClient {
>>
>> private static final Logger LOG = LoggerFactory.getLogger(Messag
>> eConsumerClient.class);
>>
>> private MessageConsumerClient() {
>> }
>>
>> public static void main(String[] args) throws Exception {
>>
>> LOG.info("About to run Kafka-camel integration...");
>>
>> CamelContext camelContext = new DefaultCamelContext();
>>
>> // Add route to send messages to Kafka
>>
>> camelContext.addRoutes(new RouteBuilder() {
>> public void configure() {
>> PropertiesComponent pc =
>> getContext().getComponent("properties",
>> PropertiesComponent.class);
>> pc.setLocation("classpath:application.properties");
>>
>> log.info("About to start route: Kafka Server -> Log ");
>> onException(Exception.class).process(new Processor() {
>> @Override
>> public void process(Exchange exchange) throws
>> Exception {
>> System.out.println("Exception occurred!!");
>> }
>> });
>> from("kafka:{{consumer.topic}}
>> ?brokers={{kafka.host}}:{{kafka.port}}"
>> + "&maxPollRecords={{consumer.maxPollRecords}}"
>> + "&consumersCount={{consumer.consumersCount}}"
>> + "&seekTo={{consumer.seekTo}}"
>> + "&groupId={{consumer.group}}")
>> .routeId("FromKafka")
>> .log("${body}");
>> }
>> });
>>
>> camelContext.start();
>>
>> //
>> // change start
>> //
>> final Collection<Endpoint> endpoints =
>> camelContext.getEndpoints();
>> for (Endpoint endpoint : endpoints) {
>> if (endpoint instanceof DefaultEndpoint) {
>> final DefaultEndpoint endpoint1 = (DefaultEndpoint)
>> endpoint;
>> endpoint1.setBridgeErrorHandler(true);
>> final HashMap<String, Object> consumerProperties = new
>> HashMap<>();
>> consumerProperties.put("backoffMultiplier", 10);
>> consumerProperties.put("backoffErrorThreshold", 5);
>> endpoint1.setConsumerProperties(consumerProperties);
>> }
>> }
>> //
>> // change end here
>> //
>>
>> // let it run for 5 minutes before shutting down
>> Thread.sleep(5 * 60 * 1000);
>>
>> camelContext.stop();
>> }
>>
>> }
>>
>>
>>
>>
>>
>> 2017-11-25 19:18 GMT+02:00 Claus Ibsen <[email protected]>:
>>
>>> Post the stactrace so we can see from where the error is thrown.
>>>
>>>
>>> On Wed, Nov 22, 2017 at 11:01 AM, Yacov Schondorf
>>> <[email protected]> wrote:
>>> > I am trying to detect when Kafka is not available. I have modified the
>>> > example -
>>> >
>>> > https://github.com/apache/camel/blob/master/examples/camel-e
>>> xample-kafka/src/main/java/org/apache/camel/example/kafka/
>>> MessageConsumerClient.java
>>> > and
>>> > added following code right after camelContext.start()
>>> >
>>> >
>>> >
>>> > final Collection<Endpoint> endpoints =
>>> camelContext.getEndpoints();
>>> >
>>> > for (Endpoint endpoint : endpoints) {
>>> >
>>> > if (endpoint instanceof DefaultEndpoint) {
>>> >
>>> > final DefaultEndpoint endpoint1 = (DefaultEndpoint)
>>> > endpoint;
>>> >
>>> > endpoint1.setBridgeErrorHandler(true);
>>> >
>>> > final HashMap<String, Object> consumerProperties = new
>>> > HashMap<>();
>>> >
>>> > consumerProperties.put("backoffMultiplier", 10);
>>> >
>>> > consumerProperties.put("backoffErrorThreshold", 5);
>>> >
>>> > endpoint1.setConsumerProperties(consumerProperties);
>>> >
>>> > }
>>> >
>>> > }
>>> >
>>> >
>>> >
>>> > I ran the main() and hoped to see the consumer stopping the attempts to
>>> > connect to Kafka after 5 tries, but this did not work. I keep getting
>>> > output messages of “Connection to node -1 could not be established.
>>> Broker
>>> > may not be available.”
>>> >
>>> > Is this the right way to go? What am I doing wrong?
>>> >
>>> >
>>> > Thanks.
>>>
>>>
>>>
>>> --
>>> Claus Ibsen
>>> -----------------
>>> http://davsclaus.com @davsclaus
>>> Camel in Action 2: https://www.manning.com/ibsen2
>>>
>>
>>
>>
