create-update-delete-cloneset

README

Create CloneSet

This example program demonstrates the fundamental operations for managing on CloneSet resources, such as Create, List, Update and Delete.

You can adopt the source code from this example to write programs that manage other types of resources through the Kubernetes API.

Running this example

Make sure you have a Kubernetes cluster with kruise-manager installed and kubectl is configured:

kubectl get nodes

Compile this example on your workstation:

cd create-update-delete-cloneset
go build -o ./app

Now, run this application on your workstation with your local kubeconfig file:

./app
# or specify a kubeconfig file with flag
./app -kubeconfig=$HOME/.kube/config

Running this command will execute the following operations on your cluster:

1. Create CloneSet: This will create a 2 replica CloneSet. Verify with kubectl get pods and kubectl get cloneset.
2. Update CloneSet: This will update the CloneSet resource created in previous step by setting the replica count to 1 and changing the container image to nginx:1.13. You are encouraged to inspect the retry loop that handles conflicts. Verify the new replica count and container image with kubectl describe cloneset demo.
3. List CloneSet: This will retrieve CloneSet in the default namespace and print their names and replica counts.
4. Delete CloneSet: This will delete the CloneSet object and its dependent pod resource. Verify with kubectl get cloneset.

Each step is separated by an interactive prompt. You must hit the Return key to proceed to the next step. You can use these prompts as a break to take time to run kubectl and inspect the result of the operations executed.

You should see an output like the following:

Created cloneset "demo-cloneset".
-> Press Return key to continue.

Updating cloneset...
Updated cloneset...
-> Press Return key to continue.

Listing clonesets in namespace "default":
 * demo-cloneset (1 replicas)
-> Press Return key to continue.

Deleting cloneset...
Deleted cloneset.

Cleanup

Successfully running this program will clean the created artifacts. If you terminate the program without completing, you can clean up the created deployment with:

kubectl delete cloneset demo-cloneset

Troubleshooting