Fix suppressGoMetrics, rename it to suppressDefaultMetrics (#967)

Fixes #944

Author: jotak

README.md

@@ -876,7 +876,7 @@ A sample is the following:
 
 ```
 metricsSettings:
-  suppressGoMetrics: true
+  suppressDefaultMetrics: true
   prefix: flp_operational_
   port: 9102
 
@@ -887,7 +887,7 @@ In addition, there are default metrics reported by `Go`, which are also directed
 The port to which these metrics are made available is specified in the `port` configuration parameter.
 If a `prefix` is specified, then the specified prefix is prepended to each of the operational metrics generated by FLP.
 A different `prefix` may be specified on an `encode prom` stage to be prepended to the prometheus metrics defined in that stage.
-The `suppressGoMetrics` parameter may be set to `true` in order to suppress the reporting of the `Go` and process metrics in the prometheus client interface.
+The `suppressDefaultMetrics` parameter may be set to `true` in order to suppress the reporting of the default Prometheus metrics, such as `Go` and process metrics.
 
 # Development
 

hack/examples/docker-ipfix-config.yaml

@@ -1,6 +1,9 @@
 log-level: info
 health:
   port: 8080
+metricsSettings:
+  suppressDefaultMetrics: true
+  prefix: flp_
 pipeline:
   - name: ingest
   - name: conntrack

pkg/config/config.go

@@ -75,7 +75,7 @@ type MetricsSettings struct {
 	DisableGlobalServer    bool   `yaml:"disableGlobalServer,omitempty" json:"disableGlobalServer,omitempty" doc:"disabling the global metrics server makes operational metrics unavailable. If prometheus-encoding stages are defined, they need to contain their own metrics server parameters."`
 	Prefix                 string `yaml:"prefix,omitempty" json:"prefix,omitempty" doc:"prefix for names of the operational metrics"`
 	NoPanic                bool   `yaml:"noPanic,omitempty" json:"noPanic,omitempty"`
-	SuppressGoMetrics      bool   `yaml:"suppressGoMetrics,omitempty" json:"suppressGoMetrics,omitempty" doc:"filter out Go and process metrics"`
+	SuppressDefaultMetrics bool   `yaml:"suppressDefaultMetrics,omitempty" json:"suppressDefaultMetrics,omitempty" doc:"filter out default Prometheus metrics such as Go and process metrics"`
 }
 
 // PerfSettings allows setting some internal configuration parameters

pkg/prometheus/prom_server.go

@@ -73,9 +73,12 @@ func InitializePrometheus(settings *config.MetricsSettings) *PromServer {
 		return nil
 	}
 	r := prom.DefaultGatherer
-	if settings.SuppressGoMetrics {
+	if settings.SuppressDefaultMetrics {
 		// set up private prometheus registry
-		r = prom.NewRegistry()
+		nr := prom.NewRegistry()
+		prom.DefaultRegisterer = nr
+		prom.DefaultGatherer = nr
+		r = nr
 	}
 	SharedServer = StartServerAsync(&settings.PromConnectionInfo, "", r)
 	return SharedServer