CDI: Injecting a bean produced by a dependency

Question

I'm creating a maven dependency, which has a MessageHandler class. Alongside which there is a MessageHandlerProduceer class:

public class MessageHandlerProducer {

    @Produces
    public MessageHandler messageHandler() {
        return new MessageHandler();
    }
}

Having listed the dependency in the core project, and when I'm trying to inject the MessageHandler bean, I'm getting the following error:

Build step io.quarkus.arc.deployment.ArcProcessor#validate threw an exception: javax.enterprise.inject.spi.DeploymentException: javax.enterprise.inject.UnsatisfiedResolutionException: Unsatisfied dependency for type com.example.MessageHandler and qualifiers [@Default]

Answer 1

In a multi-module setup, we need information of beans provided by sibling modules. The easiest way to generate those information is enabling Jandex support through the jandex-plugin.

For Maven, the following snippet should be added to the module providing the producer:

<build>
  <plugins>
    <plugin>
      <groupId>org.jboss.jandex</groupId>
      <artifactId>jandex-maven-plugin</artifactId>
      <version>1.1.0</version>
      <executions>
        <execution>
          <id>make-index</id>
          <goals>
            <goal>jandex</goal>
          </goals>
        </execution>
      </executions>
    </plugin>
  </plugins>
</build>

For gradle, the following snippet can be used:

plugins {
    id 'org.kordamp.gradle.jandex' version '0.11.0'
}

Both snippets are taken from the documentation linked above and are only included to make this answer self-contained. Credits for those go to Red Hat, as they are the maintainer of quarkus and provide the snippets in the documentation linked above.