EventListener not triggered

Data Services
1

Hey,
I am trying to create an EventListener in Data Services, but it won’t register. This is my code:

Entrypoint (BapApplicationServer.java)

package com.mgmtp.a12.template.server;

import com.mgmtp.a12.dataservices.server.app.ServerApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
class BapServerApplication extends ServerApplication {

    // Workaround for "NoSuchMethodException: main()" when starting in Docker
    public static void main(String[] args) {
        ServerApplication.main(args);
    }
}

Class with the EventListener logic

package com.mgmtp.a12.template.server;

import com.mgmtp.a12.dataservices.attachment.events.AttachmentAfterCreateEvent;
import org.springframework.context.event.EventListener;
import org.springframework.stereotype.Component;

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStreamReader;

@Component
public class PDFAttachmentListener {
    @EventListener
    public void afterCreateListener(AttachmentAfterCreateEvent event) throws IOException {
        System.out.println("triggered")
        String path = event.getAttachment().getAbsolutePath();
        System.out.println(path);

        // other logic 
    }
}

Are there some special steps I need to do? Shouldn’t Spring automatically find the Component and register the EventListener? Both classes are in the same package, so that shouldn’t really be a problem?

2

Hi @anon11273509,

The events are not published in different instances. If you want to create a DS extension where you will implement @EventListeneryou also need to include component scanning from DS packages and define dependencies to DS BOM files. Please see the fullstack project template how it is done there. I.e. this is our example of how to create DS extension:

buildscript {
	dependencies {
	}
}


description = 'examples-extending-server'

configurations {
	bootExtendedServerJar.canBeResolved = false
}

artifacts {
	bootExtendedServerJar(tasks.bootJar)
}

dependencies {
	implementation project(':dataservices-server-app')
	implementation(libs.uaaAuthenticationUserExtension) { exclude group: 'jakarta.servlet', module: 'jakarta.servlet-api' } 
	implementation libs.uaaAuthorization
	implementation libs.uaaAuthorizationA12Extension
	implementation libs.hazelcast
	implementation libs.hazelcastSpring
	implementation libs.hazelcastHibernate
	compileOnly libs.springBootDevtools

	testImplementation libs.testng
	testImplementation libs.springTest
	testImplementation libs.springBootTest
	testImplementation libs.springSecurityTest
	testImplementation libs.hamcrest
	bootExtendedServerJarTask(project(path: ':examples:examples-extending-server', configuration: 'bootExtendedServerJar'))
}

springBoot {
	mainClass.set 'com.mgmtp.a12.dataservices.server.app.ServerApplication'
}

bootRun {
	systemProperties 'workDir': "${project.rootDir}/"
}

I have gutted this from our example-server so I hope I have not made some mistakes :slight_smile:

3

Moin,

the Eventlisteners are only picked up from dataservices packages, as configured in this version of the project template. (This was change in the later release of the Project Template 202206.3.0)
This should be fixed by doing the following two things:

  1. Change the mainClass in server/app/build.gradle 
mainClass = 'com.mgmtp.a12.dataservices.server.app.ServerApplication'

to this:

mainClass = 'com.mgmtp.a12.template.server.BapServerApplication'
  1. Change the BapServerApplication to not use the dataservices spring application anymore
package com.mgmtp.a12.template.server;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
class BapServerApplication {
    public static void main(String[] args) {
        SpringApplication.run(BapServerApplication.class, args);
    }
}