Remote dev-watch development with WildFly Jar Maven Plugin

By Emmanuel Hugonnet | September 14, 2022

The 8.0.0.Alpha2 version of the WildFly bootable JAR Maven plugin has been released.

This release is not yet Final, as it is only there to gather feedback on a new feature that simplifies development on the "cloud" using the dev-watch goal.

For people who are not familiar with WildFly bootable JAR and its dev-watch goal, I strongly recommend that you read this blog post that covers it in details.

Dev-watch goal

The current dev-watch goal, although offering an efficient workflow to develop WildFly applications, requires the bootable application or server to run locally, in the same place as the project. The improvement made on this release is to allow the bootable application or server to run remotely so that it can be in an environment that is closer to the target runtime environment. We are going to use this example to see how we can work remotely.

Important

This application applies the script anonymous-management.cli which disable security on the Management API of WildFly, please make sure not to include it when going to production.

Developping with a docker container.

Build and run the application with docker

The first step is to create the container image where the application is running. For this we are going to use a very simple Dockerfile:

FROM registry.access.redhat.com/ubi8/openjdk-11:latest
COPY --chown=jboss:root target/*.jar /deployments/.
RUN chmod -R ug+rwX /deployments/.

To build that container image we are executing:

$ mvn clean install
$ podman build -f Dockerfile -t remote-microprofile-config:latest

And then we are going to run the container and expose the ports 8080 and 9990:

$ podman run -p 8080:8080 -p 9990:9990 -it remote-microprofile-config:latest

Develop and update this application

Now we need to run the dev-watch goal and remotely attach to the Wildfly Management API. For this we need to execute the following command line:

$ mvn org.wildfly.plugins:wildfly-jar-maven-plugin:8.0.0.Alpha2:dev-watch \
-Dwildfly.bootable.remote=true \
-Dwildfly.bootable.remote.username=admin \
-Dwildfly.bootable.remote.password=passW0rd! \
-Dwildfly.hostname=${container.ip.address}

Check that the application is running properly :

$ curl http://${container.ip.address}:8080
config1 = Value from Config1 comes from an env var in the DeploymentConfig
config2 = Value for config2 comes from a properties file inside the application
config3 = Default value for config3 comes from my code

Once this is done you can edit the code and your changes will be automatically pushed to the remote container. For example:

Change the config2 property value to be "Hello from dev-watch remote" in the file: src/main/resources/META-INF/microprofile-config.properties.
Save your changes
The application is redeployed and the new configuration will be taken into account:

$ curl http://${container.ip.address}:8080
config1 = Value from Config1 comes from an env var in the DeploymentConfig
config2 = Hello from dev-watch remote
config3 = Default value for config3 comes from my code

Developping on OpenShift.

Build and run the application with OpenShift

We first need to build the application :

$ mvn clean install

Then to deploy it you need to drag and drop the produced remote-microprofile-config-bootable.jar on the Topology page on OpenShift. Now we need to expose the management API of WilFly by first editing the service to add a TCP port for 9990, and then add a route to that port:

$ oc create route edge management-remote-microprofile-config-bootable --service=remote-microprofile-config-bootable --port=9990 --insecure-policy='Redirect'

Develop and update this application

Now we need to run the dev-watch goal and remotely attach to the Wildfly Management API. For this we need to execute the following command line:

$ mvn -P bootable-jar-remote -Dwildfly.hostname=$(oc get route management-remote-microprofile-config-bootable --template='{{ .spec.host }}') install

You may also use a command like this one:

$ mvn org.wildfly.plugins:wildfly-jar-maven-plugin:8.0.0.Alpha2:dev-watch \
-Dwildfly.bootable.remote=true \
-Dwildfly.port=443 \
-Dwildfly.bootable.remote.protocol=remote+https \
-Dwildfly.hostname=$(oc get route management-remote-microprofile-config-bootable --template='{{ .spec.host }}')

Check that the application is running properly :

$ curl https://$(oc get route remote-microprofile-config-bootable --template='{{ .spec.host }}')
config1 = Value from Config1 comes from an env var in the DeploymentConfig
config2 = Value for config2 comes from a properties file inside the application
config3 = Default value for config3 comes from my code

Once this is done you can edit the code and your changes will be automatically pushed to the OpenShift instance. For example:

Change the config2 property value to be "Hello from dev-watch remote" in the file: src/main/resources/META-INF/microprofile-config.properties.
Save your changes
The application is redeployed and the new configuration will be taken into account:

$ curl https://$(oc get route remote-microprofile-config-bootable --template='{{ .spec.host }}')
config1 = Value from Config1 comes from an env var in the DeploymentConfig
config2 = Hello from dev-watch remote
config3 = Default value for config3 comes from my code

Conclusion

We hope that you are seeing the benefits of the new features that this release is bringing.

We would really appreciate your feedback on the dev-watch goal. We aim toward a smooth and efficient first class WildFly developer experience and we need you there!

Thank-you.