Axon server connector

Axon Server
1

Do you have a Java example without an Axon server?

I used MySQL version 8.0.33
But I got org.hibernate.hql.internal.ast.QuerySyntaxException: DomainEventEntry Error

this GitHub - dharanikumarp/axon-kafka-example: Example of axon-kafka module usage for 5 years ago

2

We need a Java example in which there is no Axon server and there is Kafka and Mongo with the latest version of axon?

3

In that case, you still have no command or query gateway. Also, as it’s not advised to use Mongo as an event store, you likely want to add a relational database to the mix. So that comes down to adding the Axon Starter, disabling Axon Server, and adding the Mongo and Kafka extension. Maybe the Kafka example might be a good start. It is in Kotlin, not Java through. Alternatively there is a Mongo example, also in Kotlin.

4 
<axon.version>4.8.2</axon.version>

and spring boot 3.1.1
org.axonframework.extensions.mongo axon-mongo-spring 4.8.0 org.axonframework.extensions.kafka axon-kafka-spring-boot-starter 4.8.0

this dependency are ok?

5

Yes, you could also import the Axon bom, so you only need to manage a single dependency.

6

when we use the last version that was mentioned before the question I get an Error.
“Consider defining a bean named ‘kafkaMessageSource’ in your configuration”.
my config in cusrumer:
spring.data.mongodb.host=localhost
spring.data.mongodb.port=27017
spring.data.mongodb.database=accounts

spring.application.name=accountoperations-query

axon.eventhandling.processors.Accounts.source=kafkaMessageSource
axon.eventhandling.processors.Accounts.mode=TRACKING

axon.serializer.general=xstream
axon.kafka.client-id=accountconsumer
axon.kafka.default-topic=account_topic
axon.kafka.consumer.group-id=account_group
axon.kafka.consumer.auto-offset-reset=earliest
axon.kafka.consumer.bootstrap-servers=127.0.0.1:9092
axon.distributed.enabled=true
axon.kafka.consumer.enable-auto-commit=true
axon.kafka.consumer.event-processor-mode=pooled_streaming
logging.level.root=info
server.port=9090
@Configuration
@AutoConfigureAfter(AxonAutoConfiguration.class)
public class AccountQueryConfig {

 @ConditionalOnMissingBean
 @Bean
  public KafkaMessageConverter<String, byte[]> kafkaMessageConverter(
		@Qualifier("eventSerializer") Serializer eventSerializer) {
	return new DefaultKafkaMessageConverter
			.Builder().serializer(eventSerializer)
			.build();
}

}

the producer is correct and I can send messages on the topic but the customer can not see them.

7

You likely need something like this. Please note it’s important to differentiate ‘local’ events, the ones directly stored in an EventStore which are there forever. And ‘integration’ events which are sent via Kafka and might not be stored forever.

8

We have a big team working on Axon Serverless. and version 4.8.2, Java, Kafka, and MongoDB, but we can’t find an example that is correct or a tutorial that is correct and correct in Spring Boot on your site. And it took a long time to understand the issue
Do you have a source where we can use the axon with spring boot sooner?

9

I’m not sure what you are asking for. Do you have any issues still? By not using Axon Server some things are becoming more complicated. Especially when running multiple distributed applications. As such I don’t know what you mean with a correct example. All the bits and pieces should be there. And how you combine them very much depends on the kind of applications, and how you split them.

10

You are right, I implemented the correct example with your help, but it took too long.
I am sorry that we are taking so much of your time to solve the problem.
For example, now I want to use Tracking Tokens in a MongoDB serverless project, but the site is only a description.
I am really grateful to you