anwarchk / my-app-deployment

Hands-On: GitOps with Kustomize and Argo CD

Hands-On

1. Install Kustomize

brew install kustomize
kustomize version

2. Fork The Example Repo

• Open https://github.com/gitops-workshop/my-app-deployment
• Click “Fork”.

3. Clone Your Fork

In your terminal:

export username=... ;# your Github username in lowercase
git clone [email protected]:${username}/my-app-deployment.git
cd my-app-deployment

4. Build The Base

kustomize build base

Note: The above URL should start with "git@" and you'll need to enter your username.

5. Create An Overlay

mkdir -p overlays/dev

cat > overlays/dev/kustomization.yaml <<EOL
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
  - ../../base
EOL

kustomize build overlays/dev
git add . && git commit -am "add dev overlay"
git push

6. Change The Name Prefix

cd overlays/dev
kustomize edit set nameprefix ${username}-
git diff
kustomize build
git commit -am "set name prefix"
git push

7. Open Argo CD And Create Your App

• Open https://argo-cd-kubecon.apps.argoproj.io/
• Click "Login Via Github"
• Click "New application"

Field	Value
Application name:	${username}
Project:	default
Sync policy:	Manual
Repository:	https://github.com/${username}/my-app-deployment
Revision:	HEAD
Path:	overlays/dev
Cluster:	https://kubernetes.default.svc
Namespace:	default

8. Sync Your App

• Click "Sync".
• Click "Synchronize" in the Sliding panel.

9. Upgrade Your App

kustomize edit set image gitopsworkshop/my-app:v2
git diff
kustomize build

git commit -am "upgrade to version 2"
git push

• Detect git changes: "Refresh"
• Preview Differences: "App Diff"
• Deploy New Version: "Sync"

10. Troubleshoot Degraded App

1. Open app
2. Find the red heart
3. Clik on the resource and check each tab

11. Emergency Rollback

• Click "History And Rollback"
• Click "..." button in the last row
• Click "Rollback"
• Click "Ok" in the modal panel

12. GitOps Rollback

git revert $(git rev-parse HEAD)
git push