Setting Up To Deploy With Helm 3

Helm helps you manage Kubernetes applications — Helm Charts help you define, install, and upgrade even the most complex Kubernetes application.

We do not have the time to completely explain creating a Helm chart for this application, and besides we want you to check out my colleague Jamie Land telling you about Helm. In this case, our Quarkus setup will be using Eclipse JKube to create our Helm chart for us:

1. Open the Maven pom.xml and locate the Eclipse JKube plugin (Either kubernetes-maven-plugin or openshift-maven-plugin depending on your target)
2. Add some customizations to the plugin config so allow for overriding the application configuration

   <configuration>
     <enricher>
       <config>
         <jkube-openshift-route> <!-- Used for OpenShift Routes -->
           <generateRoute>true</generateRoute>
           <tlsInsecureEdgeTerminationPolicy>Redirect</tlsInsecureEdgeTerminationPolicy>
           <tlsTermination>edge</tlsTermination>
         </jkube-openshift-route>
       </config>
     </enricher>
     <resources>
       <ingress> <!-- Used for Kubernetes Ingress -->
         <ingressTlsConfigs>
           <ingressTlsConfig>
              <hosts>
                <host>foo.bar.com</host>
              </hosts>
              <secretName>testsecret-tls</secretName>
           </ingressTlsConfig>
         </ingressTlsConfigs>
         <ingressRules>
           <ingressRule>
             <host>foo.bar.com</host>
             <paths>
               <path>
                 <pathType>Prefix</pathType>
                 <path>/foo</path>
                 <serviceName>service1</serviceName>
                 <servicePort>8080</servicePort>
               </path>
             </paths>
           </ingressRule>
         </ingressRules>
       </ingress>
     </resources>
     <helm>
       <chart>todoapp</chart>
       <keywords>quarkus,todo,postgresql,rest,api,openapi</keywords>
     </helm>
   </configuration>

3. Create the directory src/main/jkube where we can add additional Kubernetes/OpenShift resources
4. Add a ConfigMap to contain our application settings:

   data:
     application.yaml: |
       mp:
         openapi:
           scan:
             disable: 'true'
       quarkus:
         datasource:
           db-kind :  postgresql
             username: ${TODODB_USER:tododb}
             password: ${TODODB_PASS:tododb}
             jdbc:
               driver: org.postgresql.Driver
               url: ${TODODB_URL:jdbc:postgresql://localhost:5432/hibernate_orm_test}
       log:
         console:
           json: 'true'
       oidc:
         auth-sever-url: https://oidc.example.c

   TIP

   Notice that you do NOT need to add a metadata header to the configmap. JKube will do that based on your configuration

5. Add a Deployment for our Database pod to src/main/jkube/postgresql-deployment.yml

   metadata:
     annotations:
       configmap.jkube.io/update-on-change: ${project.artifactId}
   spec:
     template:
       spec:
         volumes:
           - name: config
             configMap:
               name: ${project.artifactId}
               items:
               - key: application.yaml
                 path: application.yaml
         containers:
           - volumeMounts:
             - name: config
               mountPath: /deployments/config
           - env:
             - name: JAVA_OPTS
               value: '-Dquarkus.config.locations=/deployments/config'
             - name: TODODB_USER
               value: tododb
             - name: TODODB_PASS
               value: tododb
             - name: TODODB_URL
               value: 'jdbc:postgresql://tododb:5432/todo'

6. Generate the Helm chart

   ./mvnw oc:resource oc:helm    ### For OpenShift
   ./mvnw k8s:resource k8s:helm  ### For Kubernetes

7. The Helm chart will be created in target/jkube/helm/todoapp and can be run from there.