Deploy a telemetry plugin

Deploy the telemetry backend as a container image, create a devfile v2 plugin, and host the plugin on a web server so that DevWorkspaces can load it.

This guide demonstrates hosting the plugin on an Apache web server on Kubernetes. In production, deploy the plugin file to a corporate web server.

Prerequisites

An active kubectl session with administrative permissions to the destination Kubernetes cluster. See Overview of kubectl.
You have a running instance of Eclipse Che.
You have a telemetry backend created and tested. See Create a telemetry backend.

Procedure

Package the Quarkus application as a container image and push it to a container registry by using one of the following options. See the Quarkus documentation for details.

Option A: JVM image

Create a Dockerfile.jvm:

FROM registry.access.redhat.com/ubi8/openjdk-11:1.11

ENV LANG='en_US.UTF-8' LANGUAGE='en_US:en'

COPY --chown=185 target/quarkus-app/lib/ /deployments/lib/
COPY --chown=185 target/quarkus-app/*.jar /deployments/
COPY --chown=185 target/quarkus-app/app/ /deployments/app/
COPY --chown=185 target/quarkus-app/quarkus/ /deployments/quarkus/

EXPOSE 8080
USER 185

ENTRYPOINT ["java", "-Dquarkus.http.host=0.0.0.0", "-Djava.util.logging.manager=org.jboss.logmanager.LogManager", "-Dquarkus.http.port=${DEVWORKSPACE_TELEMETRY_BACKEND_PORT}", "-jar", "/deployments/quarkus-run.jar"]

Build and push the image:

mvn package && \
docker build -f src/main/docker/Dockerfile.jvm -t image:tag .

Option B: Native image

Create a Dockerfile.native:

FROM registry.access.redhat.com/ubi8/ubi-minimal:8.5
WORKDIR /work/
RUN chown 1001 /work \
    && chmod "g+rwX" /work \
    && chown 1001:root /work
COPY --chown=1001:root target/*-runner /work/application

EXPOSE 8080
USER 1001

CMD ["./application", "-Dquarkus.http.host=0.0.0.0", "-Dquarkus.http.port=${DEVWORKSPACE_TELEMETRY_BACKEND_PORT}"]

Build and push the image:

mvn package -Pnative -Dquarkus.native.container-build=true && \
docker build -f src/main/docker/Dockerfile.native -t image:tag .

Create a plugin.yaml devfile v2 file representing a DevWorkspace plugin that runs your custom backend in a DevWorkspace Pod. For more information about devfile v2, see Devfile v2 documentation.

schemaVersion: 2.1.0
metadata:
  name: devworkspace-telemetry-backend-plugin
  version: 0.0.1
  description: A Demo telemetry backend
  displayName: Devworkspace Telemetry Backend
components:
  - name: devworkspace-telemetry-backend-plugin
    attributes:
      workspaceEnv:
        - name: DEVWORKSPACE_TELEMETRY_BACKEND_PORT
          value: '4167'
    container:
      image: <your_image>
      env:
        - name: WELCOME_MESSAGE
          value: 'hello world!'

where:

<your_image>: The container image built in the previous step.
WELCOME_MESSAGE: Set the value for the welcome.message optional configuration property.

Create a ConfigMap object that references the plugin.yaml file:

$ kubectl create configmap --from-file=plugin.yaml -n eclipse-che telemetry-plugin-yaml

Create a manifest.yaml file with a Deployment, a Service, and a Route to expose the Apache web server. The Deployment references this ConfigMap object and places the plugin.yaml in the /var/www/html directory.

kind: Deployment
apiVersion: apps/v1
metadata:
  name: apache
spec:
  replicas: 1
  selector:
    matchLabels:
      app: apache
  template:
    metadata:
      labels:
        app: apache
    spec:
      volumes:
        - name: plugin-yaml
          configMap:
            name: telemetry-plugin-yaml
            defaultMode: 420
      containers:
        - name: apache
          image: 'registry.redhat.io/rhscl/httpd-24-rhel7:latest'
          ports:
            - containerPort: 8080
              protocol: TCP
          resources: {}
          volumeMounts:
            - name: plugin-yaml
              mountPath: /var/www/html
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxUnavailable: 25%
      maxSurge: 25%
  revisionHistoryLimit: 10
  progressDeadlineSeconds: 600
---
kind: Service
apiVersion: v1
metadata:
  name: apache
spec:
  ports:
    - protocol: TCP
      port: 8080
      targetPort: 8080
  selector:
    app: apache
  type: ClusterIP
---
kind: Route
apiVersion: route.openshift.io/v1
metadata:
  name: apache
spec:
  host: apache-che.apps-crc.testing
  to:
    kind: Service
    name: apache
    weight: 100
  port:
    targetPort: 8080
  wildcardPolicy: None

Apply the manifest:
```
$ kubectl apply -f manifest.yaml
```

Verification

After the deployment has started, confirm that plugin.yaml is available in the web server:
```
$ curl apache-che.apps-crc.testing/plugin.yaml
```

Additional resources