Chapter 2. Build and Run a Java Application on the JBoss EAP for OpenShift Image

The following workflow demonstrates using the Source-to-Image (S2I) process to build and run a Java application on the JBoss EAP for OpenShift image.

As an example, the kitchensink quickstart is used in this procedure. It demonstrates a Jakarta EE web-enabled database application using Jakarta Server Faces, Jakarta Contexts and Dependency Injection, Jakarta Enterprise Beans, Jakarta Persistence, and Jakarta Bean Validation. See the kitchensink quickstart that ships with JBoss EAP 7 for more information.

2.1. Prerequisites

This workflow assumes that you already have an active OpenShift Online subscription and that you have installed the OpenShift CLI.

2.2. Prepare OpenShift for Application Deployment

  1. Log in to your OpenShift instance using the oc login command.
  2. Create a new project in OpenShift.

    A project allows a group of users to organize and manage content separately from other groups. You can create a project in OpenShift using the following command.

    $ oc new-project <project_name>

    For example, for the kitchensink quickstart, create a new project named eap-demo using the following command.

    $ oc new-project eap-demo
  3. Optional: Create a keystore and a secret.

    Note

    Creating a keystore and a secret is required if you are using any HTTPS-enabled features in your OpenShift project. For example, if you are using the eap74-https-s2i template, you must create a keystore and secret.

    This workflow demonstration for the kitchensink quickstart does not use an HTTPS template, so a keystore and secret are not required.

    1. Create a keystore.

      Warning

      The following commands generate a self-signed certificate, but for production environments Red Hat recommends that you use your own SSL certificate purchased from a verified Certificate Authority (CA) for SSL-encrypted connections (HTTPS).

      You can use the Java keytool command to generate a keystore:

      $ keytool -genkey -keyalg RSA -alias <alias_name> -keystore <keystore_filename.jks> -validity 360 -keysize 2048

      For example, for the kitchensink quickstart, use the following command to generate a keystore:

      $ keytool -genkey -keyalg RSA -alias eapdemo-selfsigned -keystore keystore.jks -validity 360 -keysize 2048
    2. Create a secret from the keystore.

      Create a secret from the previously created keystore using the following command.

      $ oc create secret generic <secret_name> --from-file=<keystore_filename.jks>

      For example, for the kitchensink quickstart, use the following command to create a secret.

      $ oc create secret generic eap7-app-secret --from-file=keystore.jks

2.3. Import the Latest JBoss EAP for OpenShift Imagestreams and Templates

You must import the latest JBoss EAP for OpenShift imagestreams and templates for your JDK into the namespace of your OpenShift project.

Note

Log in to the Red Hat Container Registry using your Customer Portal credentials to import the JBoss EAP imagestreams and templates. For more information, see Red Hat Container Registry Authentication.

Import command for JDK 8

oc replace -f \
https://raw.githubusercontent.com/jboss-container-images/jboss-eap-openshift-templates/eap74/eap74-openjdk8-image-stream.json

This command imports the following imagestreams and templates.

  • The JDK 8 builder imagestream: jboss-eap74-openjdk8-openshift
  • The JDK 8 runtime imagestream: jboss-eap74-openjdk8-runtime-openshift
Note

If you use OpenShift 3 and create an EAP 7.4 ImageStream for the first time, run the following command instead of oc replace:

oc create -f https://raw.githubusercontent.com/jboss-container-images/jboss-eap-openshift-templates/eap74/eap74-openjdk8-image-stream.json

Import command for JDK 11

oc replace -f \
https://raw.githubusercontent.com/jboss-container-images/jboss-eap-openshift-templates/eap74/eap74-openjdk11-image-stream.json

This command imports the following imagestreams and templates.

  • The JDK 11 builder imagestream: jboss-eap74-openjdk11-openshift
  • The JDK 11 runtime imagestream: jboss-eap74-openjdk11-runtime-openshift

Import command for templates

for resource in \
  eap74-amq-persistent-s2i.json \
  eap74-amq-s2i.json \
  eap74-basic-s2i.json \
  eap74-https-s2i.json \
  eap74-sso-s2i.json

do
  oc replace -f \
https://raw.githubusercontent.com/jboss-container-images/jboss-eap-openshift-templates/eap74/templates/${resource}
done

This command imports all templates specified in the command.

Note

The JBoss EAP imagestreams and templates imported using these commands are only available within that OpenShift project.

If you want to import the image streams and templates into a different project, add the -n PROJECT_NAME to the oc replace line of the command. For example:

...
oc replace -n PROJECT_NAME --force -f
...

If you use the cluster-samples-operator, refer to the OpenShift documentation on configuring the cluster samples operator. See Configuring the Samples Operator for details about configuring the cluster samples operator.

2.4. Deploy a JBoss EAP Source-to-Image (S2I) Application to OpenShift

After you import the images and templates, you can deploy applications to OpenShift.

Prerequisites

Optional: A template can specify default values for many template parameters, and you might have to override some, or all, of the defaults. To see template information, including a list of parameters and any default values, use the command oc describe template TEMPLATE_NAME.

Procedure

  1. Create a new OpenShift application that uses the JBoss EAP for OpenShift image and the source code of your Java application. You can use one of the provided JBoss EAP for OpenShift templates for S2I builds. You can also choose to provision a trimmed server.

    For example, to deploy the kitchensink quickstart using the JDK 8 builder image, enter the following command to use the eap74-basic-s2i template in the eap-demo project, created in Prepare OpenShift for Application Deployment, with the kitchensink source code on GitHub. This quickstart does not support the trimming capability.

    oc new-app --template=eap74-basic-s2i \ 1
     -p IMAGE_STREAM_NAMESPACE=eap-demo \ 2
     -p EAP_IMAGE_NAME=jboss-eap74-openjdk8-openshift:7.4.0 \ 3
     -p EAP_RUNTIME_IMAGE_NAME=jboss-eap74-openjdk8-runtime-openshift:7.4.0 \ 4
     -p SOURCE_REPOSITORY_URL=https://github.com/jboss-developer/jboss-eap-quickstarts \ 5
     -p SOURCE_REPOSITORY_REF=7.4.x \ 6
     -p CONTEXT_DIR=kitchensink 7
    1
    The template to use.
    2
    The latest imagestreams and templates were imported into the project’s namespace, so you must specify the namespace where to find the imagestream. This is usually the project’s name.
    3
    The name of the EAP builder image stream for JDK8.
    4
    The name of the EAP runtime image stream for JDK8.
    5
    URL to the repository containing the application source code.
    6
    The Git repository reference to use for the source code. This can be a Git branch or tag reference.
    7
    The directory within the source repository to build.

    As another example, to deploy the helloworld-html5 quickstart using the JDK 11 runtime image and trimming JBoss EAP to include only the jaxrs-server layer, enter the following command. The command uses the eap74-basic-s2i template in the eap-demo project, created in Prepare OpenShift for Application Deployment, with the helloworld-html5 source code on GitHub.

    oc new-app --template=eap74-basic-s2i \ 1
     -p IMAGE_STREAM_NAMESPACE=eap-demo \ 2
     -p EAP_IMAGE_NAME=jboss-eap74-openjdk11-openshift:7.4.0 \ 3
     -p EAP_RUNTIME_IMAGE_NAME=jboss-eap74-openjdk11-runtime-openshift:7.4.0 \ 4
     -p SOURCE_REPOSITORY_URL=https://github.com/jboss-developer/jboss-eap-quickstarts \ 5
     -p SOURCE_REPOSITORY_REF=7.4.x \ 6
     -p GALLEON_PROVISION_LAYERS=jaxrs-server \ 7
     -p CONTEXT_DIR=helloworld-html5 8
    1
    The template to use.
    2
    The latest imagestreams and templates were imported into the project’s namespace, so you must specify the namespace where to find the imagestream. This is usually the project’s name.
    3
    The name of the EAP builder image stream for JDK11.
    4
    The name of the EAP runtime image stream for JDK11.
    5
    URL to the repository containing the application source code.
    6
    The Git repository reference to use for the source code. This can be a Git branch or tag reference.
    7
    Provision a trimmed server with only the jaxrs-server layer.
    8
    The directory within the source repository to build.
    Note

    You might also want to configure environment variables when creating your new OpenShift application.

    For example, if you are using an HTTPS template such as eap74-https-s2i, you must specify the required HTTPS environment variables HTTPS_NAME, HTTPS_PASSWORD, and HTTPS_KEYSTORE to match your keystore details.

    Note

    If the template uses AMQ, you must include the AMQ_IMAGE_NAME parameter with the appropriate value.

    If the template uses SSO, you must include the SSO_IMAGE_NAME parameter with the appropriate value.

  2. Retrieve the name of the build configuration.

    $ oc get bc -o name
  3. Use the name of the build configuration from the previous step to view the Maven progress of the build.

    $ oc logs -f buildconfig/BUILD_CONFIG_NAME

    For example, for the kitchensink quickstart, the following command shows the progress of the Maven build.

    $ oc logs -f buildconfig/eap-app

2.5. Post deployment tasks

Depending on your application, some tasks might need to be performed after your OpenShift application has been built and deployed. This might include exposing a service so that the application is viewable from outside of OpenShift, or scaling your application to a specific number of replicas.

  1. Get the service name of your application using the following command.

    $ oc get service
  2. Expose the main service as a route so you can access your application from outside of OpenShift. For example, for the kitchensink quickstart, use the following command to expose the required service and port.

    $ oc expose service/eap-app --port=8080
    Note

    If you used a template to create the application, the route might already exist. If it does, continue on to the next step.

  3. Get the URL of the route.

    $ oc get route
  4. Access the application in your web browser using the URL. The URL is the value of the HOST/PORT field from the previous command’s output.

    If your application does not use the JBoss EAP root context, append the context of the application to the URL. For example, for the kitchensink quickstart, the URL might be http://HOST_PORT_VALUE/kitchensink/.

  5. Optionally, you can also scale up the application instance by running the following command. This increases the number of replicas to 3.

    $ oc scale deploymentconfig DEPLOYMENTCONFIG_NAME --replicas=3

    For example, for the kitchensink quickstart, use the following command to scale up the application.

    $ oc scale deploymentconfig eap-app --replicas=3

2.6. Chained Build Support in JBoss EAP for OpenShift

JBoss EAP for OpenShift supports chained builds in OpenShift.

JBoss EAP for OpenShift templates employ chained builds. When you use these templates, two builds result:

  • An intermediate image named [application name]-build-artifacts
  • The final image, [application name]

For details about chained builds, see the OpenShift documentation.