Merge pull request #10416 from k8s-infra-cherrypick-robot/cherry-pick…

…-10410-to-release-1.6

[release-1.6] 📖 Add workload bootstrap with GitOps

docs/book/src/SUMMARY.md

@@ -23,6 +23,7 @@
         - [Kubeadm based control plane management](./tasks/control-plane/kubeadm-control-plane.md)
         - [MicroK8s based control plane management](./tasks/control-plane/microk8s-control-plane.md)
     - [Updating Machine Infrastructure and Bootstrap Templates](tasks/updating-machine-templates.md)
+    - [Workload bootstrap using GitOps](tasks/workload-bootstrap-gitops.md)
     - [Automated Machine management](./tasks/automated-machine-management/index.md)
       - [Scaling](./tasks/automated-machine-management/scaling.md)
       - [Autoscaling](./tasks/automated-machine-management/autoscaling.md)

docs/book/src/tasks/workload-bootstrap-gitops.md

@@ -0,0 +1,107 @@
+# Workload bootstrap using GitOps
+
+Cluster API can be utilized in combination with the [Cluster API addon provider for helm (CAAPH)](https://github.com/kubernetes-sigs/cluster-api-addon-provider-helm/blob/main/docs/quick-start.md) to install and configure a GitOps agent and then the GitOps agent hydrates clusters automatically with various workloads.
+
+## Prerequisites
+
+Follow the quickstart setup guide for your provider but ensure that CAAPH is installed via including the `addon=helm` with either:
+
+1. [clusterctl](https://cluster-api.sigs.k8s.io/user/quick-start#initialize-the-management-cluster) using `clusterctl init --infrastructure ### --addon helm` or
+1. [Cluster API Operator](https://cluster-api.sigs.k8s.io/user/quick-start-operator) using `helm install capi-operator capi-operator/cluster-api-operator ... --set infrastructure=#### --set addon=helm`
+
+## Bootstrap ManagedCluster using ArgoCD
+
+Add the labels `argoCDChart: enabled` and `guestbook: enabled` to your desired workload cluster yaml file in the `Cluster` metadata section, for example:
+
+```yaml
+apiVersion: cluster.x-k8s.io/v1beta1
+kind: Cluster
+metadata:
+  name: my-cluster
+  namespace: default
+  labels:
+    argoCDChart: enabled
+    guestbook: enabled
+```
+
+Then create and `kubectl apply -f` the following file on the management cluster to install the ArgoCD agent and the sample guestbook app to the workload cluster via the argo helm charts using CAAPH:
+
+```yaml
+apiVersion: addons.cluster.x-k8s.io/v1alpha1
+kind: HelmChartProxy
+metadata:
+  name: argocd
+spec:
+  clusterSelector:
+    matchLabels:
+      argoCDChart: enabled
+  repoURL: https://argoproj.github.io/argo-helm
+  chartName: argo-cd
+  options:
+    waitForJobs: true
+    wait: true
+    timeout: 5m
+    install:
+      createNamespace: true
+---
+apiVersion: addons.cluster.x-k8s.io/v1alpha1
+kind: HelmChartProxy
+metadata:
+  name: argocdguestbook
+spec:
+  clusterSelector:
+    matchLabels:
+      guestbook: enabled
+  repoURL: https://argoproj.github.io/argo-helm
+  chartName: argocd-apps
+  options:
+    waitForJobs: true
+    wait: true
+    timeout: 5m
+    install:
+      createNamespace: true
+  valuesTemplate: |
+    applications:
+      - name: guestbook
+        namespace: argocd
+        finalizers:
+        - resources-finalizer.argocd.argoproj.io
+        project: default
+        sources:
+          - repoURL: https://github.com/argoproj/argocd-example-apps.git
+            path: guestbook
+            targetRevision: HEAD
+        destination:
+          server: https://kubernetes.default.svc
+          namespace: guestbook
+        syncPolicy:
+          automated:
+            prune: false
+            selfHeal: false
+          syncOptions:
+          - CreateNamespace=true
+        revisionHistoryLimit: null
+    ignoreDifferences:
+      - group: apps
+        kind: Deployment
+        jsonPointers:
+        - /spec/replicas
+    info:
+    - name: url
+      value: https://argoproj.github.io/
+```
+
+This will automatically install ArgoCD in the ArgoCD namespace and the guestbook application into the guestbook namespace.  Adding or labeling additional clusters with `argoCDChart: enabled` and `guestbook: enabled` will automatically install the ArgoCD agent and the guestbook application and there is no need to create additional CAAPH HelmChartProxy entries.
+
+The ArgoCD console can be viewed by connecting to the workload cluster and then doing the following:
+
+```bash
+# Get the admin password
+kubectl get secrets argocd-initial-admin-secret -n argocd --template="{{index .data.password | base64decode}}"
+kubectl port-forward service/capiargo-argocd-server -n default 8080:443
+# and then open the browser on http://localhost:8080 and accept the certificate
+```
+
+The Guestbook application deployment can be seen once logged into the ArgoCD console. Since the GitOps agent points to the git repository, any changes to the repository will automatically update the workload cluster.  The git repository could be configured to utilize the [App of Apps pattern](https://argo-cd.readthedocs.io/en/stable/operator-manual/cluster-bootstrapping/#app-of-apps-pattern) to install all platform requirements for the cluster. The App of Apps pattern is a single application that installs all other applications and configurations for the cluster.
+
+This same pattern could also utilize the Flux agent using the [Flux helm charts](https://github.com/fluxcd-community/helm-charts/) being installed and configured by CAAPH.