In this article we show HOW-TO create a docker image containing WildFly with a Java application deployed in it; the docker image is ready to be run in OpenShift, Kubernetes or just locally with docker or podman;

The process is broken to pieces in order to provide a deep understanding of all the moving parts;

The first 3 steps are not meant to be executed during the usual development life-cycle: their goal is just to show how those artifacts are produced;

1. wildfly-preview-cloud-galleon-pack : provides e.g. health endpoint

   git clone git@github.com:wildfly-extras/wildfly-cloud-galleon-pack.git 
   cd wildfly-cloud-galleon-pack
   mvn install -DskipTests
   --> .m2/repository/org/wildfly/cloud/wildfly-preview-cloud-galleon-pack/2.0.0.Alpha5-SNAPSHOT
   

2. wildfly : the "Jakarta EE 10" server to run our application

   git clone git@github.com:wildfly/wildfly.git
   cd wildfly
   mvn install -DskipTests
   --> .m2/repository/org/wildfly/wildfly-galleon-pack/27.0.0.Alpha5-SNAPSHOT
   --> .m2/repository/org/wildfly/wildfly-preview-feature-pack/27.0.0.Alpha5-SNAPSHOT
   

3. wildfly-maven-plugin : the maven plugin capable of assembling server+application from wildfly-galleon-pack and wildfly-preview-cloud-galleon-pack

   git clone git@github.com:wildfly/wildfly-maven-plugin.git
   cd wildfly-maven-plugin
   mvn install -DskipTests
   --> .m2/repository/org/wildfly/plugins/wildfly-maven-plugin/4.0.0.Beta4-SNAPSHOT
   

4. wildfly-s2itest-app : the "Jakarta EE 10" application

   git clone git@github.com:wildfly/wildfly-s2i.git
   cd wildfly-s2i/test/test-app
   

Adjust the wildfly-maven-plugin configuration in order to use the versions we just built of the following artifacts:

• wildfly-maven-plugin
• wildfly-preview-feature-pack
• wildfly-preview-cloud-galleon-pack

  <plugin>
    <groupId>org.wildfly.plugins</groupId>
    <artifactId>wildfly-maven-plugin</artifactId>
    <version>4.0.0.Beta4-SNAPSHOT</version>
    <configuration>
        <!-- some tests check for the provisioned galleon layers -->
        <record-provisioning-state>true</record-provisioning-state>
        <feature-packs>
            <feature-pack>
                <location>org.wildfly:wildfly-preview-feature-pack:27.0.0.Alpha5-SNAPSHOT</location>
            </feature-pack>
            <feature-pack>
                <location>org.wildfly.cloud:wildfly-preview-cloud-galleon-pack:2.0.0.Alpha5-SNAPSHOT</location>
            </feature-pack>
        </feature-packs>
        <layers>
            <layer>cloud-server</layer>
        </layers>
        <runtime-name>ROOT.war</runtime-name>
    </configuration>
    <executions>
        <execution>
            <goals>
                <goal>package</goal>
            </goals>
        </execution>
    </executions>
  </plugin>
  

mvn install -P openshift
--> ./target/server

./target/server contains WildFly with the Java application deployed in it

Check our server actually works:

./target/server/bin/standalone.sh

curl http://127.0.0.1:9990/health/live
curl http://127.0.0.1:9990/health/ready

1. create a runnable image

Create a Dockerfile with the following content (see github.com/wildfly/wildfly-s2i/blob/main/ex..)

ARG runtime_image=quay.io/wildfly/wildfly-runtime-jdk11:latest
FROM ${runtime_image}
COPY --chown=jboss:root target/server $JBOSS_HOME
RUN rm -f /opt/server/standalone/configuration/standalone_xml_history/standalone.last.xml /opt/server/standalone/configuration/standalone_xml_history/standalone.boot.xml
RUN chmod -R ug+rwX $JBOSS_HOME

Then create and run the image:

podman build -t myapp:latest .
podman run -p 8081:8080 -p 9990:9990 --rm myapp:latest

curl http://127.0.0.1:9990/health/live
curl http://127.0.0.1:9990/health/ready