demo-app: canary rollout + health analysis (auto-rollback)

manifests/demo-app/analysistemplate.yaml

@@ -0,0 +1,39 @@
+# Canary ke har step par chalta hai. App theek jawab de raha hai ya nahi -
+# 5 baar check, 2 se zyada fail hue to rollout wapas purane version par.
+apiVersion: argoproj.io/v1alpha1
+kind: AnalysisTemplate
+metadata:
+  name: app-health
+  namespace: demo-app
+spec:
+  args:
+    - name: service
+  metrics:
+    - name: http-health
+      interval: 20s
+      count: 5
+      successCondition: result == "1"
+      failureLimit: 2
+      provider:
+        job:
+          spec:
+            backoffLimit: 0
+            template:
+              spec:
+                restartPolicy: Never
+                containers:
+                  - name: check
+                    image: curlimages/curl:8.11.1
+                    command: [sh, -c]
+                    args:
+                      - >-
+                        curl -sf --max-time 5 http://{{args.service}}/health
+                        >/dev/null && echo 1 || echo 0
+                    resources:
+                      requests: { cpu: "10m", memory: "16Mi" }
+                      limits:   { cpu: "100m", memory: "64Mi" }
+                    securityContext:
+                      runAsNonRoot: true
+                      runAsUser: 65534
+                      allowPrivilegeEscalation: false
+                      capabilities: { drop: ["ALL"] }

manifests/demo-app/rollout.yaml

@@ -1,5 +1,5 @@
-apiVersion: apps/v1
-kind: Deployment
+apiVersion: argoproj.io/v1alpha1
+kind: Rollout
 metadata:
   name: demo-app
   namespace: demo-app
@@ -9,11 +9,26 @@ spec:
   selector:
     matchLabels:
       app: demo-app
+  # Canary: naya version thode traffic par chalta hai, har step ke baad
+  # analysis hota hai. Analysis fail hua to Rollouts KHUD purane version par
+  # wapas le jaata hai - koi insaan nahi chahiye.
   strategy:
-    type: RollingUpdate
-    rollingUpdate:
+    canary:
       maxUnavailable: 0
       maxSurge: 1
+      analysis:
+        templates:
+          - templateName: app-health
+        startingStep: 1
+        args:
+          - name: service
+            value: demo-app.demo-app.svc.cluster.local
+      steps:
+        - setWeight: 25
+        - pause: { duration: 60s }
+        - setWeight: 50
+        - pause: { duration: 60s }
+        - setWeight: 100
   template:
     metadata:
       labels: