Add Service to Fortio so that the sidecar can become ready. (istio#12353

)

* Add annotation to Fortio so that the sidecar can become ready.

* Configure Envoy to record stats so that the Circuit Breaking task can use them

* Use a Service to allow Fortio to become ready.  It is more clear than using an annotation.

samples/httpbin/sample-client/fortio-deploy.yaml

@@ -1,3 +1,16 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: fortio
+  labels:
+    app: fortio
+spec:
+  ports:
+  - port: 8080
+    name: http
+  selector:
+    app: fortio
+---
 apiVersion: apps/v1beta1
 kind: Deployment
 metadata:
@@ -6,6 +19,11 @@ spec:
   replicas: 1
   template:
     metadata:
+      annotations:
+        # This annotation causes Envoy to serve cluster.outbound statistics via 15000/stats
+        # in addition to the stats normally served by Istio.  The Circuit Breaking example task
+        # gives an example of inspecting Envoy stats.
+        sidecar.istio.io/statsInclusionPrefixes: cluster.outbound,cluster_manager,listener_manager,http_mixer_filter,tcp_mixer_filter,server,cluster.xds-grpc
       labels:
         app: fortio
     spec: