Merge pull request #14309 from bergerhoffer/OSDOCS-34

OSDOCS-34: Updating with the latest examples

Author: bergerhoffer

modules/osdk-monitoring-prometheus-metrics-helper-modifying-port.adoc

@@ -3,16 +3,16 @@
 // * applications/operator_sdk/osdk-monitoring-prometheus.adoc
 
 [id="osdk-monitoring-prometheus-metrics-helper-modifying-port-{context}"]
-= Modifying metrics port
+= Modifying the metrics port
 
 Operator authors can modify the port that metrics are exposed on.
 
 .Prerequisites
 
-- Go-based Operator generated using the Operator SDK
-- Kubernetes-based cluster with the Prometheus Operator deployed
+* Go-based Operator generated using the Operator SDK
+* Kubernetes-based cluster with the Prometheus Operator deployed
 
 .Procedure
 
-. In the generated Operator's `cmd/manager/main.go` file, change the `var
-metricsPort int32 = 8383` variable.
+* In the generated Operator's `cmd/manager/main.go` file, change the value of `metricsPort` in the line `var
+metricsPort int32 = 8383`.

modules/osdk-monitoring-prometheus-metrics-helper.adoc

@@ -5,16 +5,15 @@
 [id="osdk-monitoring-prometheus-metrics-helper-{context}"]
 = Metrics helper
 
-In Go-based Operators generated using the Operator SDK, the following helper
+In Go-based Operators generated using the Operator SDK, the following
 function exposes general metrics about the running program:
 
 [source,go]
 ----
 func ExposeMetricsPort(ctx context.Context, port int32) (*v1.Service, error)
 ----
 
-These metrics are inherited from the `controller-runtime` library API. The
-metrics are by default served on `:8383/metrics`.
+These metrics are inherited from the `controller-runtime` library API. By default, the metrics are served on `0.0.0.0:8383/metrics`.
 
 A Service object is created with the metrics port exposed, which can be then
 accessed by Prometheus. The Service object is garbage collected when the leader
@@ -25,29 +24,34 @@ Operators generated using the Operator SDK:
 
 [source,go]
 ----
-    import(
-     "github.com/operator-framework/operator-sdk/pkg/metrics"
-	"sigs.k8s.io/controller-runtime/pkg/manager"
-    )
-
-    // Change the below variables to serve metrics on different host or port.
-    var metricsHost = "0.0.0.0" <1>
-    var metricsPort int32 = 8383 <2>
-
+import(
+    "github.com/operator-framework/operator-sdk/pkg/metrics"
+    "sigs.k8s.io/controller-runtime/pkg/manager"
+)
+
+var (
+    // Change the below variables to serve metrics on a different host or port.
+    metricsHost       = "0.0.0.0" <1>
+    metricsPort int32 = 8383 <2>
+)
+...
+func main() {
+    ...
     // Pass metrics address to controller-runtime manager
-	mgr, err := manager.New(cfg, manager.Options{
-		Namespace:          namespace,
-		MetricsBindAddress: fmt.Sprintf("%s:%d", metricsHost, metricsPort),
-	})
+    mgr, err := manager.New(cfg, manager.Options{
+        Namespace:          namespace,
+        MetricsBindAddress: fmt.Sprintf("%s:%d", metricsHost, metricsPort),
+    })
 
     ...
-
-	// Create Service object to expose the metrics port.
-	_, err = metrics.ExposeMetricsPort(ctx, metricsPort)
-	if err != nil {
+    // Create Service object to expose the metrics port.
+    _, err = metrics.ExposeMetricsPort(ctx, metricsPort)
+    if err != nil {
         // handle error
-		log.Info(err.Error())
-	}
+        log.Info(err.Error())
+    }
+    ...
+}
 ----
-<1> Host the metrics are exposed on.
-<2> Port the metrics are exposed on.
+<1> The host that the metrics are exposed on.
+<2> The port that the metrics are exposed on.

modules/osdk-monitoring-prometheus-servicemonitor-creating.adoc

@@ -11,22 +11,36 @@ newly created Service.
 
 .Prerequisites
 
-- Go-based Operator generated using the Operator SDK
-- Kubernetes-based cluster with the Prometheus Operator deployed
+* Go-based Operator generated using the Operator SDK
+* Kubernetes-based cluster with the Prometheus Operator deployed
 
 .Procedure
 
-. Add the `metrics.CreateServiceMonitor()` helper function to your Operator code,
-creating only one ServiceMonitor per application and namespace:
+* Add the `metrics.CreateServiceMonitor()` helper function to your Operator code:
 +
 [source,go]
 ----
-    import "github.com/operator-framework/operator-sdk/pkg/metrics"
+import(
+    "k8s.io/api/core/v1"
+    "github.com/operator-framework/operator-sdk/pkg/metrics"
+    "sigs.k8s.io/controller-runtime/pkg/client/config"
+)
+func main() {
 
-    serviceMonitors, err := metrics.CreateServiceMonitors(config *rest.Config, ns string, services []*v1.Service) <1>
+    ...
+    // Populate below with the Service(s) for which you want to create ServiceMonitors.
+    services := []*v1.Service{}
+    // Create one ServiceMonitor per application per namespace.
+    // Change the below value to name of the Namespace you want the ServiceMonitor to be created in.
+    ns := "default"
+    // restConfig is used for talking to the Kubernetes apiserver
+    restConfig := config.GetConfig()
+
+    // Pass the Service(s) to the helper function, which in turn returns the array of ServiceMonitor objects.
+    serviceMonitors, err := metrics.CreateServiceMonitors(restConfig, ns, services)
     if err != nil {
-        <2>
+        // Handle errors here.
     }
+    ...
+}
 ----
-<1> Pass the Service(s) to the helper function, which in turn returns the ServiceMonitor object.
-<2> Handle errors here.

modules/osdk-monitoring-prometheus-servicemonitor.adoc

@@ -15,6 +15,6 @@ generate a ServiceMonitor Custom Resource (CR) based on it.
 
 .Additional resources
 
-- See the
+* See the
 link:https://github.com/coreos/prometheus-operator/blob/7a25bf6b6bb2347dacb235659b73bc210117acc7/Documentation/design.md#servicemonitor[Prometheus Operator documentation]
-for more about the ServiceMonitor CRD.
+for more information about the ServiceMonitor CRD.