Add Prometheus exporter.

cmd/node_problem_detector.go

@@ -24,6 +24,7 @@ import (
 
 	"k8s.io/node-problem-detector/cmd/options"
 	"k8s.io/node-problem-detector/pkg/exporters/k8sexporter"
+	"k8s.io/node-problem-detector/pkg/exporters/prometheusexporter"
 	"k8s.io/node-problem-detector/pkg/problemdaemon"
 	"k8s.io/node-problem-detector/pkg/problemdetector"
 	"k8s.io/node-problem-detector/pkg/types"
@@ -57,6 +58,10 @@ func main() {
 		exporters = append(exporters, ke)
 		glog.Info("K8s exporter started.")
 	}
+	if pe := prometheusexporter.NewExporterOrDie(npdo); pe != nil {
+		exporters = append(exporters, pe)
+		glog.Info("Prometheus exporter started.")
+	}
 	if len(exporters) == 0 {
 		glog.Fatalf("No exporter is successfully setup")
 	}

cmd/options/options.go

@@ -52,6 +52,12 @@ type NodeProblemDetectorOptions struct {
 	// ApiServerOverride is the custom URI used to connect to Kubernetes ApiServer.
 	ApiServerOverride string
 
+	// prometheusExporter options
+	// PrometheusServerPort is the port to bind the Prometheus scrape endpoint. Use 0 to disable.
+	PrometheusServerPort int
+	// PrometheusServerAddress is the address to bind the Prometheus scrape endpoint.
+	PrometheusServerAddress string
+
 	// problem daemon options
 
 	// SystemLogMonitorConfigPaths specifies the list of paths to system log monitor configuration
@@ -96,6 +102,11 @@ func (npdo *NodeProblemDetectorOptions) AddFlags(fs *pflag.FlagSet) {
 	fs.StringVar(&npdo.ServerAddress, "address",
 		"127.0.0.1", "The address to bind the node problem detector server.")
 
+	fs.IntVar(&npdo.PrometheusServerPort, "prometheus-port",
+		20257, "The port to bind the Prometheus scrape endpoint. Prometheus exporter is enabled by default at port 20257. Use 0 to disable.")
+	fs.StringVar(&npdo.PrometheusServerAddress, "prometheus-address",
+		"127.0.0.1", "The address to bind the Prometheus scrape endpoint.")
+
 	for _, problemDaemonName := range problemdaemon.GetProblemDaemonNames() {
 		npdo.MonitorConfigPaths[problemDaemonName] = &[]string{}
 		fs.StringSliceVar(