fix: blue-green example uses autoPromotionEnabled: false

blue-green/README.md

@@ -1,30 +1,57 @@
 # Blue Green
 
-The blue green strategy is not supported by built-in Kubernetes Deployment but available via third-party Kubernetes controller.
-This example demonstrates how to implement blue-green deployment via [Argo Rollouts](https://github.com/argoproj/argo-rollouts):
+The [blue green strategy](https://argoproj.github.io/argo-rollouts/concepts/#blue-green) is not supported by Kubernetes Deployments, 
+but it is available via [Argo Rollouts](https://github.com/argoproj/argo-rollouts). This example demonstrates how to implement a blue-green 
+deployment using Argo CD and Argo Rollouts together.
 
-1. Install Argo Rollouts controller: https://github.com/argoproj/argo-rollouts#installation
-2. Create a sample application and sync it.
+## Prerequisites:
+
+1. Install Argo CD: https://argo-cd.readthedocs.io/en/stable/operator-manual/installation/#core 
+2. Install Argo Rollouts: https://argoproj.github.io/argo-rollouts/installation/
+3. Install the kubectl rollouts plugin: https://argoproj.github.io/argo-rollouts/installation/#kubectl-plugin-installation
+
+
+## Walkthrough
+
+1. Let's start by creating an Argo CD Application and sync it with the helm chart in this git repository:
+
+```
+argocd app create blue-green --repo https://github.com/argoproj/argocd-example-apps --dest-server https://kubernetes.default.svc --dest-namespace default --path blue-green && argocd app sync blue-green
+```
+
+Once the application is synced, you can access it using `blue-green-helm-guestbook` service:
 
 ```
-argocd app create --name blue-green --repo https://github.com/argoproj/argocd-example-apps --dest-server https://kubernetes.default.svc --dest-namespace default --path blue-green && argocd app sync blue-green
+kubectl port-forward svc/blue-green-helm-guestbook 8080:80 -n default
 ```
 
-Once the application is synced you can access it using `blue-green-helm-guestbook` service.
+After running the command above, the application can be viewed at localhost:8080.
 
-3. Change image version parameter to trigger blue-green deployment process:
+2. Change the image version parameter to trigger the blue-green deployment process:
 
 ```
 argocd app set blue-green -p image.tag=0.2 && argocd app sync blue-green
 ```
 
-Now application runs `ks-guestbook-demo:0.1` and `ks-guestbook-demo:0.2` images simultaneously.
-The `ks-guestbook-demo:0.2` is still considered `blue` available only via preview service `blue-green-helm-guestbook-preview`.
+After running the command above, the Application runs `ks-guestbook-demo:0.1` and `ks-guestbook-demo:0.2` images simultaneously.
+The `ks-guestbook-demo:0.2` is still considered blue or only available via the preview service `blue-green-helm-guestbook-preview`. 
 
-4. Promote `ks-guestbook-demo:0.2` to `green` by patching `Rollout` resource:
+You can run the following to view the blue preview service:
 
 ```
-argocd app patch-resource blue-green --kind Rollout --resource-name blue-green-helm-guestbook --patch '{ "status": { "verifyingPreview": false } }' --patch-type 'application/merge-patch+json'
+kubectl port-forward svc/blue-green-helm-guestbook-preview 8081:80 -n default
 ```
 
-This promotes `ks-guestbook-demo:0.2` to `green` status and `Rollout` deletes old replica which runs `ks-guestbook-demo:0.1`.
+The blue preview version of the application will be available at localhost:8081, but the active version of the application at localhost:8080 
+is still displaying the older version of the application.
+
+3. Promote `ks-guestbook-demo:0.2` to `green` by patching `Rollout` resource:
+
+```
+kubectl argo rollouts promote blue-green-helm-guestbook -n default
+```
+
+This promotes `ks-guestbook-demo:0.2` to `green` status and the `Rollout` deletes the old replica which runs `ks-guestbook-demo:0.1`.
+
+If you stop and rerun `kubectl port-forward svc/blue-green-helm-guestbook 8080:80 -n default` again, you should see the new 
+version is now available via the active service at localhost:8080.

blue-green/templates/rollout.yaml

@@ -18,6 +18,7 @@ spec:
     blueGreen:
       activeService: {{ template "helm-guestbook.fullname" . }}
       previewService: {{ template "helm-guestbook.fullname" . }}-preview
+      autoPromotionEnabled: false
   template:
     metadata:
       labels: