Add CanaryDeployment kind

- bootstrap the deployments. services and Istio virtual service
- use google/go-cmp to detect changes in the deployment pod spec

artifacts/canaries/canary.yaml

@@ -0,0 +1,37 @@
+apiVersion: flagger.app/v1beta1
+kind: CanaryDeployment
+metadata:
+  name: podinfo
+  namespace: test
+spec:
+  targetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name: podinfo
+  service:
+    port: 9898
+    gateways:
+    - public-gateway.istio-system.svc.cluster.local
+    hosts:
+    - app.istio.weavedx.com
+  canaryAnalysis:
+    # max number of failed metric checks
+    # before rolling back the canary
+    threshold: 5
+    # max traffic percentage routed to canary
+    # percentage (0-100)
+    maxWeight: 50
+    # canary increment step
+    # percentage (0-100)
+    stepWeight: 10
+    metrics:
+    - name: istio_requests_total
+      # minimum req success rate (non 5xx responses)
+      # percentage (0-100)
+      threshold: 99
+      interval: 1m
+    - name: istio_request_duration_seconds_bucket
+      # maximum req duration P99
+      # milliseconds
+      threshold: 500
+      interval: 30s

artifacts/canaries/deployment.yaml

@@ -0,0 +1,70 @@
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: podinfo
+  namespace: test
+  labels:
+    app: podinfo
+spec:
+  strategy:
+    rollingUpdate:
+      maxUnavailable: 0
+    type: RollingUpdate
+  selector:
+    matchLabels:
+      app: podinfo
+  template:
+    metadata:
+      annotations:
+        prometheus.io/scrape: "true"
+      labels:
+        app: podinfo
+    spec:
+      containers:
+      - name: podinfod
+        image: quay.io/stefanprodan/podinfo:1.2.0
+        imagePullPolicy: IfNotPresent
+        ports:
+        - containerPort: 9898
+          name: http
+          protocol: TCP
+        command:
+        - ./podinfo
+        - --port=9898
+        - --level=info
+        - --random-delay=false
+        - --random-error=false
+        env:
+        - name: PODINFO_UI_COLOR
+          value: blue
+        livenessProbe:
+          exec:
+            command:
+            - podcli
+            - check
+            - http
+            - localhost:9898/healthz
+          initialDelaySeconds: 5
+          failureThreshold: 3
+          periodSeconds: 10
+          successThreshold: 1
+          timeoutSeconds: 1
+        readinessProbe:
+          exec:
+            command:
+            - podcli
+            - check
+            - http
+            - localhost:9898/readyz
+          initialDelaySeconds: 5
+          failureThreshold: 3
+          periodSeconds: 3
+          successThreshold: 1
+          timeoutSeconds: 1
+        resources:
+          limits:
+            cpu: 2000m
+            memory: 512Mi
+          requests:
+            cpu: 10m
+            memory: 64Mi

artifacts/flagger/crd.yaml

@@ -64,4 +64,48 @@ spec:
                           pattern: "^[0-9]+(m)"
                         threshold:
                           type: number
-
+---
+apiVersion: apiextensions.k8s.io/v1beta1
+kind: CustomResourceDefinition
+metadata:
+  name: canarydeployments.flagger.app
+spec:
+  group: flagger.app
+  version: v1beta1
+  versions:
+  - name: v1beta1
+    served: true
+    storage: true
+  names:
+    plural: canarydeployments
+    singular: canarydeployment
+    kind: CanaryDeployment
+  scope: Namespaced
+  validation:
+    openAPIV3Schema:
+      properties:
+        spec:
+          required:
+          - canaryAnalysis
+          properties:
+            canaryAnalysis:
+              properties:
+                threshold:
+                  type: number
+                maxWeight:
+                  type: number
+                stepWeight:
+                  type: number
+                metrics:
+                  type: array
+                  properties:
+                    items:
+                      type: object
+                      properties:
+                        name:
+                          type: string
+                        interval:
+                          type: string
+                          pattern: "^[0-9]+(m)"
+                        threshold:
+                          type: number