MessageBodyWriter not found Error when running from fatjar - jax-rs

Question

I'm getting this error only when running from the fatjar, mvn run:java works as expected.
SEVERE: MessageBodyWriter not found for media type=application/json, type=class com.example.Greeting, genericType=class com.example.Greeting.
I'm using moxy for json handling. I tried jackson, made no difference. Tried grizzly instead o jetty, same issue.
Here are my pom dependencies:
<dependencies>
<dependency>
<groupId>org.glassfish.jersey.containers</groupId>
<artifactId>jersey-container-jetty-http</artifactId>
</dependency>
<dependency>
<groupId>org.glassfish.jersey.inject</groupId>
<artifactId>jersey-hk2</artifactId>
</dependency>
<dependency>
<groupId>org.glassfish.jersey.media</groupId>
<artifactId>jersey-media-moxy</artifactId>
</dependency>
<dependency>
<groupId>org.glassfish.jersey.test-framework</groupId>
<artifactId>jersey-test-framework-core</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.glassfish.jersey.test-framework.providers</groupId>
<artifactId>jersey-test-framework-provider-jetty</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>${logback.version}</version>
</dependency>
</dependencies>
Shade plugin config:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>3.2.3</version>
<configuration>
<createDependencyReducedPom>true</createDependencyReducedPom>
<filters>
<filter>
<artifact>*:*</artifact>
<excludes>
<exclude>META-INF/*.SF</exclude>
<exclude>META-INF/*.DSA</exclude>
<exclude>META-INF/*.RSA</exclude>
</excludes>
</filter>
</filters>
</configuration>
<executions>
<execution>
<id>shade</id>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<!--<minimizeJar>true</minimizeJar>-->
<transformers>
<transformer implementation="org.apache.maven.plugins.shade.resource.ServicesResourceTransformer"/>
<transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
<mainClass>com.example.http.JettyHttpServer</mainClass>
</transformer>
</transformers>
</configuration>
</execution>
</executions>
</plugin>
Jersey version is 2.30.1.
Thanks!
EDIT
Contents of org.glassfish.jersey.internal.spi.AutoDiscoverable does not include org.glassfish.jersey.moxy.json.internal.MoxyJsonAutoDiscoverable
org.glassfish.jersey.logging.LoggingFeatureAutoDiscoverable
org.glassfish.jersey.internal.config.ExternalPropertiesAutoDiscoverable
According to this it should. How do I fix it?

Answer 1

Try loading the dependencies you need explicitly on code and not relying on auto discovery, registering them on Jersey.
The fat jar plug-in tries to analyze your code and see what's being used and what's not, so it can exclude references not used and make a smaller jar. The problem with auto discovery is that since there are no explicit references to some classes, the shade plug-in can just think their aren't being used so they can be removed.
I think there's a way to force them to be included on the plug-in configuration, but I don't remember that configuration from memory, you would have to search for it in the docs.