🤖 fix: remove app-of-apps ordering ambiguity in Argo example

Refactor the Argo CD example so the ApplicationSet generates one multi-source Application instead of a parent app that applies child Application resources.

This avoids cross-Application wave ordering ambiguity, adds a cascading resources finalizer for cleanup, and keeps dependency ordering at the resource level via sync waves.

---

_Generated with [`mux`](https://github.com/coder/mux) • Model: `openai:gpt-5.3-codex` • Thinking: `xhigh` • Cost: `$0.56`_

<!-- mux-attribution: model=openai:gpt-5.3-codex thinking=xhigh costs=0.56 -->

Author: ThomasK33

examples/argocd/README.md

@@ -1,9 +1,11 @@
 # Argo CD single-apply example (CloudNativePG + coder-k8s)
 
-This example bootstraps the full stack from one `ApplicationSet`:
+This example bootstraps the full stack from one `ApplicationSet`.
 
-1. CloudNativePG operator
-2. `coder-k8s` operator stack (CRDs + RBAC + deployment)
+The generated Argo CD `Application` uses multiple sources to deploy:
+
+1. CloudNativePG operator (Helm chart)
+2. `coder-k8s` operator stack (`config/crd/bases`, `config/rbac`, `deploy`)
 3. CloudNativePG PostgreSQL `Cluster`
 4. `CoderControlPlane`
 
@@ -12,7 +14,7 @@ This example bootstraps the full stack from one `ApplicationSet`:
 - A Kubernetes cluster
 - `kubectl` configured for that cluster
 - Argo CD installed (including the ApplicationSet controller)
-- Argo CD v2.6+ (required for Application `sources` in `apps/01-coder-k8s-operator.yaml`)
+- Argo CD v2.6+ (required for `spec.sources` in the generated Application)
 
 ## Apply one manifest
 
@@ -23,14 +25,18 @@ kubectl apply -f examples/argocd/applicationset.yaml
 That creates:
 
 - `ApplicationSet` `coder-k8s-stack`
-- parent `Application` `coder-k8s-stack`
-- child Applications in `examples/argocd/apps/`
+- generated `Application` `coder-k8s-stack`
+
+## Ordering behavior
 
-### Ordering behavior
+This setup avoids app-of-apps ordering ambiguity by using a single generated `Application` with multiple sources.
 
-`apps/00-cnpg-operator.yaml` and `apps/01-coder-k8s-operator.yaml` are synced in wave `0`, and `apps/02-coder-cloudnativepg.yaml` in wave `1`.
+Resource-level sync waves provide dependency ordering for workload resources:
 
-The CloudNativePG example manifests (`examples/cloudnativepg/`) also include resource-level sync waves so PostgreSQL is applied before `CoderControlPlane`.
+- `examples/argocd/resources/00-coder-system-namespace.yaml` uses `wave -1`
+- `examples/cloudnativepg/00-namespace.yaml` uses `wave 0`
+- `examples/cloudnativepg/cnpg-cluster.yaml` uses `wave 1`
+- `examples/cloudnativepg/codercontrolplane.yaml` uses `wave 2`
 
 ## Watch rollout
 
@@ -50,15 +56,15 @@ Open <http://localhost:3000/setup> and complete the setup flow.
 
 ## Customization
 
-- This example tracks `https://github.com/coder/coder-k8s.git` at `main` for child apps.
-  Update `repoURL` and `targetRevision` in `examples/argocd/apps/*.yaml` if you want to pin to a tag or use a fork.
-- `apps/00-cnpg-operator.yaml` uses `targetRevision: "*"` for the CloudNativePG chart.
-  Pin this to a specific chart version for reproducibility.
+- This example tracks `https://github.com/coder/coder-k8s.git` at `main`.
+  Update `repoURL` and `targetRevision` in `examples/argocd/applicationset.yaml` if you want to pin to a tag or use a fork.
+- The CloudNativePG chart version is configurable with `cloudnativepgChartVersion`.
+  Pin it to an explicit chart version for reproducible environments.
 
 ## Cleanup
 
 ```bash
 kubectl -n argocd delete applicationset coder-k8s-stack
 ```
 
-Depending on your storage class reclaim policy, PVCs from PostgreSQL may remain after cleanup.
+The generated `Application` includes `resources-finalizer.argocd.argoproj.io` so deleting the `ApplicationSet` cascades cleanup of managed resources. Depending on your storage class reclaim policy, PVCs from PostgreSQL may remain after cleanup.

examples/argocd/applicationset.yaml

@@ -14,24 +14,44 @@ spec:
         elements:
           - name: coder-k8s-stack
             destinationServer: https://kubernetes.default.svc
+            destinationNamespace: cnpg-system
             repoURL: https://github.com/coder/coder-k8s.git
             targetRevision: main
-            path: examples/argocd/apps
+            cloudnativepgChartVersion: "*"
   template:
     metadata:
       name: "{{ .name }}"
       namespace: argocd
+      finalizers:
+        - resources-finalizer.argocd.argoproj.io
       labels:
         app.kubernetes.io/part-of: coder-k8s-example
     spec:
       project: default
-      source:
-        repoURL: "{{ .repoURL }}"
-        targetRevision: "{{ .targetRevision }}"
-        path: "{{ .path }}"
+      sources:
+        - repoURL: https://cloudnative-pg.github.io/charts
+          chart: cloudnative-pg
+          targetRevision: "{{ .cloudnativepgChartVersion }}"
+          helm:
+            releaseName: cnpg
+        - repoURL: "{{ .repoURL }}"
+          targetRevision: "{{ .targetRevision }}"
+          path: examples/argocd/resources
+        - repoURL: "{{ .repoURL }}"
+          targetRevision: "{{ .targetRevision }}"
+          path: config/crd/bases
+        - repoURL: "{{ .repoURL }}"
+          targetRevision: "{{ .targetRevision }}"
+          path: config/rbac
+        - repoURL: "{{ .repoURL }}"
+          targetRevision: "{{ .targetRevision }}"
+          path: deploy
+        - repoURL: "{{ .repoURL }}"
+          targetRevision: "{{ .targetRevision }}"
+          path: examples/cloudnativepg
       destination:
         server: "{{ .destinationServer }}"
-        namespace: argocd
+        namespace: "{{ .destinationNamespace }}"
       syncPolicy:
         automated:
           prune: true

examples/argocd/apps/00-cnpg-operator.yaml

@@ -0,0 +1,8 @@
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: coder-system
+  annotations:
+    argocd.argoproj.io/sync-wave: "-1"
+  labels:
+    app.kubernetes.io/part-of: coder-k8s-example