rewrote prometheus metrics handling

prometheus.go

@@ -14,7 +14,7 @@ import (
 // handling
 type metrics struct {
 	// The channel to pass metrics that should be processed
-	metricsCh chan metricType
+	promRegistry *prometheus.Registry
 	// host and port where prometheus metrics will be exported
 	hostAndPort string
 }
@@ -22,56 +22,15 @@ type metrics struct {
 // newMetrics will prepare and return a *metrics
 func newMetrics(hostAndPort string) *metrics {
 	m := metrics{
-		metricsCh:   make(chan metricType),
-		hostAndPort: hostAndPort,
+		promRegistry: prometheus.NewRegistry(),
+		hostAndPort:  hostAndPort,
 	}
 
 	return &m
 }
 
-type Metricer interface {
-	Set(float64)
-}
-
-type metricType struct {
-	metric prometheus.Collector
-	value  float64
-}
-
 func (s *server) startMetrics() {
 
-	// Receive and process all metrics
-	go func() {
-		for {
-			for f := range s.metrics.metricsCh {
-				// // Try to register the metric of the interface type prometheus.Collector
-				// prometheus.Register(f.metric)
-
-				// Check the real type of the interface type
-				switch ff := f.metric.(type) {
-				case prometheus.Gauge:
-
-					// Try to register. If it is already registered we need to check the error
-					// to get the previously registered collector, and update it's value. If it
-					// is not registered we register the new collector, and sets it's value.
-					err := prometheus.Register(ff)
-					if err != nil {
-						are, ok := err.(prometheus.AlreadyRegisteredError)
-						if ok {
-							// already registered, use the one we have and put it into ff
-							ff = are.ExistingCollector.(prometheus.Gauge)
-
-						}
-					}
-
-					ff.Set(f.value)
-				}
-
-			}
-
-		}
-	}()
-
 	//http.Handle("/metrics", promhttp.Handler())
 	//http.ListenAndServe(":2112", nil)
 	n, err := net.Listen("tcp", s.metrics.hostAndPort)

server.go

@@ -11,6 +11,7 @@ import (
 
 	"github.com/nats-io/nats.go"
 	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
 )
 
 type processName string
@@ -29,17 +30,21 @@ type processes struct {
 	mu sync.RWMutex
 	// The last processID created
 	lastProcessID int
-	// metrics channel
-	metricsCh chan metricType
+	//
+	promTotalProcesses prometheus.Gauge
 }
 
 // newProcesses will prepare and return a *processes
-func newProcesses(metricsCh chan metricType) *processes {
+func newProcesses(promRegistry *prometheus.Registry) *processes {
 	p := processes{
-		active:    make(map[processName]process),
-		metricsCh: metricsCh,
+		active: make(map[processName]process),
 	}
 
+	p.promTotalProcesses = promauto.NewGauge(prometheus.GaugeOpts{
+		Name: "total_running_processes",
+		Help: "The current number of total running processes",
+	})
+
 	return &p
 }
 
@@ -91,7 +96,7 @@ func NewServer(c *Configuration) (*server, error) {
 		nodeName:       c.NodeName,
 		natsConn:       conn,
 		netListener:    nl,
-		processes:      newProcesses(metrics.metricsCh),
+		processes:      newProcesses(metrics.promRegistry),
 		toRingbufferCh: make(chan []subjectAndMessage),
 		metrics:        metrics,
 	}
@@ -156,13 +161,7 @@ func (p *processes) printProcessesMap() {
 	}
 	p.mu.Unlock()
 
-	p.metricsCh <- metricType{
-		metric: prometheus.NewGauge(prometheus.GaugeOpts{
-			Name: "total_running_processes",
-			Help: "The current number of total running processes",
-		}),
-		value: float64(len(p.active)),
-	}
+	p.promTotalProcesses.Set(float64(len(p.active)))
 
 	fmt.Println("--------------------------------------------------------------------------------------------")
 }

startup_processes.go

@@ -7,6 +7,7 @@ import (
 	"time"
 
 	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
 )
 
 func (p process) ProcessesStart() {
@@ -186,6 +187,12 @@ func (s startup) subREQHello(p process) {
 	// which is the information we pass along to generate metrics.
 	proc.procFunc = func(ctx context.Context) error {
 		sayHelloNodes := make(map[node]struct{})
+
+		promHelloNodes := promauto.NewGauge(prometheus.GaugeOpts{
+			Name: "hello_nodes",
+			Help: "The current number of total nodes who have said hello",
+		})
+
 		for {
 			// Receive a copy of the message sent from the method handler.
 			var m Message
@@ -203,13 +210,7 @@ func (s startup) subREQHello(p process) {
 			sayHelloNodes[m.FromNode] = struct{}{}
 
 			// update the prometheus metrics
-			proc.processes.metricsCh <- metricType{
-				metric: prometheus.NewGauge(prometheus.GaugeOpts{
-					Name: "hello_nodes",
-					Help: "The current number of total nodes who have said hello",
-				}),
-				value: float64(len(sayHelloNodes)),
-			}
+			promHelloNodes.Set(float64(len(sayHelloNodes)))
 		}
 	}
 	go proc.spawnWorker(p.processes, p.natsConn)