service-internal.yaml: Target metrics port by name

Use the "metrics" port name instead of port number 1936 for the router
internal service's metrics port's target.

Before this commit, the router's internal service's metrics port always
targeted port 1936 on the router pod.  However, the router pod's metrics
port can be customized, and so it is not necessarily port 1936.  As a
consequence, the service's metrics port didn't work when the router pod's
metrics port was customized.  The router pod's metrics port always has the
name "metrics", so this commit changes the service to reference the port by
name to avoid breaking when the port number changes.

This commit fixes OCPBUGS-4573.

https://issues.redhat.com/browse/OCPBUGS-4573

Follow-up to commit af653f9.

* assets/router/service-internal.yaml: Use the "metrics" port name instead
of port 1936 for the metrics port's target.
* pkg/manifests/bindata.go: Regenerate.
* pkg/operator/controller/ingress/internal_service_test.go
(Test_desiredInternalIngressControllerService): Expect the metrics port to
reference the "metrics" target port by name.
(Test_internalServiceChanged): Add a test case for changing the "metrics"
port's target port from an integer to a string.

assets/router/service-internal.yaml

@@ -17,4 +17,4 @@ spec:
   - name: metrics
     port: 1936
     protocol: TCP
-    targetPort: 1936
+    targetPort: metrics

pkg/operator/controller/ingress/internal_service.go

@@ -25,7 +25,8 @@ const (
 )
 
 // ensureInternalRouterServiceForIngress ensures that an internal service exists
-// for a given IngressController.
+// for a given IngressController.  Returns a Boolean indicating whether the
+// service exists, the current service if it does exist, and an error value.
 func (r *reconciler) ensureInternalIngressControllerService(ic *operatorv1.IngressController, deploymentRef metav1.OwnerReference) (bool, *corev1.Service, error) {
 	desired := desiredInternalIngressControllerService(ic, deploymentRef)
 	have, current, err := r.currentInternalIngressControllerService(ic)

pkg/operator/controller/ingress/internal_service_test.go

@@ -50,7 +50,7 @@ func Test_desiredInternalIngressControllerService(t *testing.T) {
 		Name:       "metrics",
 		Protocol:   "TCP",
 		Port:       int32(1936),
-		TargetPort: intstr.FromInt(1936),
+		TargetPort: intstr.FromString("metrics"),
 	}}, svc.Spec.Ports)
 }
 
@@ -116,6 +116,19 @@ func Test_internalServiceChanged(t *testing.T) {
 			},
 			expect: true,
 		},
+		{
+			description: "if .spec.ports changes by changing the metrics port's target port from an integer to a string",
+			mutate: func(svc *corev1.Service) {
+				for i := range svc.Spec.Ports {
+					if svc.Spec.Ports[i].Name == "metrics" {
+						svc.Spec.Ports[i].TargetPort = intstr.FromString("metrics")
+						return
+					}
+				}
+				panic("no metrics port found!")
+			},
+			expect: true,
+		},
 		{
 			description: "if .spec.selector changes",
 			mutate: func(svc *corev1.Service) {