Deploy Your Resource via `kpt`

<walkthrough-disable-features toc></walkthrough-disable-features>

Introduction

What is kpt?

Kpt is an OSS tool for Kubernetes packaging, which uses a standard format to bundle, publish, customize, update, and apply configuration manifests.

What you'll learn in this codelab

The difference between kpt pruning and kubectl pruning
How to enable kpt to deploy your configurations in their live state.
How to use kpt with kustomize.

This codelab is the second session. Check out the 01_kpt-validate about how to use kpt to validate your configuration before deploying to the cluster.

Prerequisites

If you are new to skaffold, you can check out the skaffold tutorials to get a basic idea. Or just follow this codelab, we will explain what happens in each step.

Install `skaffold`

Check if skaffold is installed and the installed version is >= v1.17.0
bash
```
skaffold version
```

If you haven't installed skaffold previously, run

bash

curl -Lo skaffold https://storage.googleapis.com/skaffold/builds/latest/skaffold-linux-amd64 && \
sudo install skaffold /usr/local/bin/ | bash

To upgrade skaffold to a newer version, run

bash

sudo rm -f /usr/local/bin/skaffold && curl -Lo skaffold https://storage.googleapis.com/skaffold/builds/latest/skaffold-linux-amd64 && \
sudo install skaffold /usr/local/bin/ | bash

Install `kpt`

Check if kpt is installed and the installed version is >= 0.34.0
bash
```
kpt version
```
If you haven't installed kpt previously, run
bash
```
sudo apt-get install google-cloud-sdk-kpt
```

Install `kustomize`

Check if kustomize is installed and the installed version is >= v3.4.3
bash
```
kustomize version
```

If you haven't installed kustomize previously, run

bash

curl -s "https://raw.githubusercontent.com/kubernetes-sigs/kustomize/master/hack/install_kustomize.sh"  | bash &&  sudo mv kustomize /usr/local/go/bin

Getting started

Time to complete: About 3 minutes

Run this command to start your local minikube cluster:
bash
```
minikube start
```
Once your cluster is set up, the following message is displayed:
terminal
```
Done! kubectl is now configured to use "minikube"
```

Now let's use kpt pkg to download the application example.

bash

kpt pkg get https://github.com/GoogleContainerTools/skaffold.git/codelab/02_kpt-deploy/resources/sample-app guestbook-cl2 && cd guestbook-cl2

<walkthrough-pin-section-icon></walkthrough-pin-section-icon> Tips

If you haven't used skaffold dev, you can go through this codelab.

Deploy

Time to complete: About 2 minutes

Skaffold supports using kpt to deploy your configurations to the cluster.

This deployment is equivalent to kpt live which reconciles the resources in their live states.

Compared to other deployment tools, one key advantage of the kpt deployment is the "pruning" feature. "Prune" means removing the resources from the cluster if the resources do not appear in the applied configuration.

"prune"

You may have used the following command to remove resources that are not shown up in the DIR. However, the prune operation cannot always remove the desired resource.

terminal

kubectl apply --prune -f DIR

<walkthrough-pin-section-icon></walkthrough-pin-section-icon> Extended Reading

This KEP gives a full context about the problems the kubectl "prune" may cause.

Next, you will compare the pruning result between kpt and kubectl to see why kpt is more reliable and accurate.

`kubectl` pruning

Time to complete: About 5 minutes

To enable the kubectl pruning, you can configure the <walkthrough-editor-open-file filePath="guestbook-cl2/skaffold.yaml">skaffold.yaml</walkthrough-editor-open-file>, and replace the following code in the <walkthrough-editor-select-line filePath="guestbook-cl2/skaffold.yaml" startLine="8" endLine="10" startCharacterOffset="0" endCharacterOffset="100">deploy</walkthrough-editor-select-line> section.
yaml
```
deploy:
  kubectl:
    flags:
      apply:
      - "--prune=true"
      - "--all=true"
      - "--namespace=default"
    manifests:
    - config/frontend/*.yaml
```
Run skaffold dev to deploy the resources.
bash
```
skaffold dev 
```
Now, let's open a new <walkthrough-editor-spotlight spotlightId="menu-terminal-new-terminal">terminal</walkthrough-editor-spotlight> and run the following command in the terminal. This will move the <walkthrough-editor-open-file filePath="guestbook-cl2/config/frontend/deployment.yaml">deployment.yaml</walkthrough-editor-open-file> out of the <walkthrough-editor-select-line filePath="guestbook-cl2/skaffold.yaml" startLine="16" endLine="16" startCharacterOffset="5" endCharacterOffset="28">config/frontend</walkthrough-editor-select-line>, meaning the Deployment resource should be pruned.
text
```
cd guestbook-cl2
mv config/frontend/deployment.yaml .
```
Check if the Deployment resource is pruned. You can run the following command in the terminal opened from the previous step.
text
```
kubectl get deployment
```
You should expect to see the following information, meaning the Deployment resource is not pruned.
terminal
```
NAME       READY   UP-TO-DATE   AVAILABLE   AGE
frontend   1/1     1            1           6m17s
```

<walkthrough-notification-menu-icon></walkthrough-notification-menu-icon> Note

Do not exit the skaffold dev in the first cloud shell tab, otherwise the Deployment resource is cleaned up due to the exist.

`kpt` pruning

How `kpt` prunes the resource

kpt uses a three-way merge strategy to compare the resources' previous state, current state and current desired state. This allows kpt to make changes more wisely.

Let's try it out.

First, you can exit skaffold dev with Ctrl+ C
You should add back the deployment.yaml from the previous step.
bash
```
mv deployment.yaml config/frontend/
```
In <walkthrough-editor-open-file filePath="guestbook-cl2/skaffold.yaml">skaffold.yaml</walkthrough-editor-open-file>, replace the <walkthrough-editor-select-line filePath="guestbook-cl2/skaffold.yaml" startLine="8" endLine="16" startCharacterOffset="0" endCharacterOffset="28">deploy</walkthrough-editor-select-line> with the following content.
yaml
```
deploy:
  kpt:
    dir: config
```
Tips

kpt enables pruning by default.
Run skaffold dev to deploy the resources.
bash
```
skaffold dev
```
Open a new <walkthrough-editor-spotlight spotlightId="menu-terminal-new-terminal">terminal</walkthrough-editor-spotlight>, remove the <walkthrough-editor-select-line filePath="guestbook-cl2/config/kustomization.yaml" startLine="1" endLine="1" startCharacterOffset="0" endCharacterOffset="26">deployment.yaml</walkthrough-editor-select-line> from the <walkthrough-editor-open-file filePath="guestbook-cl2/config/kustomization.yaml">kustomization.yaml</walkthrough-editor-open-file>.

You can either manually delete the line or run the following command in the new terminal
text
```
cd guestbook-cl2
sed -i '2d' ./config/kustomization.yaml
```
kpt is compatible with kustomize by default. Thus, removing the file reference from the kustomization.yaml resource will exclude deployment.yaml from the deployment.*
Check resource on the cluster side. You can run the following command in the terminal opened from the previous step.
text
```
kubectl get deployment
```
You should expect to see the following message.
terminal
```
No resources found in default namespace.
```

Conclusion

<walkthrough-conclusion-trophy></walkthrough-conclusion-trophy>

Congratulations, you know how to use kpt in skaffold! You can explore other kpt features from the skaffold.yaml reference doc.

You can also try out other kpt features like kpt pkg and kpt cfg from the user guide. They will be supported in the skaffold soon. Stay tuned!

Deploy Your Resource via `kpt`

Deploy Your Resource via kpt

Introduction

What is kpt?

What you'll learn in this codelab

Prerequisites

Install skaffold

Install kpt

Install kustomize

Getting started

Deploy

"prune"

kubectl pruning

kpt pruning

How kpt prunes the resource

Let's try it out.

Conclusion

Deploy Your Resource via `kpt`

Install `skaffold`

Install `kpt`

Install `kustomize`

`kubectl` pruning

`kpt` pruning

How `kpt` prunes the resource