$ mkdir memcached-operator
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To demonstrate the basics of setting up and running a Java-based Operator using tools and libraries provided by the Operator SDK, Operator developers can build an example Java-based Operator for Memcached, a distributed key-value store, and deploy it to a cluster.
Operator SDK CLI installed
OpenShift CLI (oc
) 4.15+ installed
Java 11+
Maven 3.6.3+
Logged into an OpenShift Container Platform 4.15 cluster with oc
with an account that has cluster-admin
permissions
To allow the cluster to pull the image, the repository where you push your image must be set as public, or you must configure an image pull secret
You can build and deploy a simple Java-based Operator for Memcached by using the Operator SDK.
Create a project.
Create your project directory:
$ mkdir memcached-operator
Change into the project directory:
$ cd memcached-operator
Run the operator-sdk init
command
with the quarkus
plugin
to initialize the project:
$ operator-sdk init \
--plugins=quarkus \
--domain=example.com \
--project-name=memcached-operator
Create an API.
Create a simple Memcached API:
$ operator-sdk create api \
--plugins quarkus \
--group cache \
--version v1 \
--kind Memcached
Build and push the Operator image.
Use the default Makefile
targets to build and push your Operator. Set IMG
with a pull spec for your image that uses a registry you can push to:
$ make docker-build docker-push IMG=<registry>/<user>/<image_name>:<tag>
Run the Operator.
Install the CRD:
$ make install
Deploy the project to the cluster. Set IMG
to the image that you pushed:
$ make deploy IMG=<registry>/<user>/<image_name>:<tag>
Create a sample custom resource (CR).
Create a sample CR:
$ oc apply -f config/samples/cache_v1_memcached.yaml \
-n memcached-operator-system
Watch for the CR to reconcile the Operator:
$ oc logs deployment.apps/memcached-operator-controller-manager \
-c manager \
-n memcached-operator-system
Delete a CR.
Delete a CR by running the following command:
$ oc delete -f config/samples/cache_v1_memcached.yaml -n memcached-operator-system
Clean up.
Run the following command to clean up the resources that have been created as part of this procedure:
$ make undeploy
See Operator SDK tutorial for Java-based Operators for a more in-depth walkthrough on building a Java-based Operator.