add prometheus exporter

.github/workflows/build.yml

@@ -10,5 +10,6 @@ jobs:
       - uses: actions/setup-go@v5
         with:
           go-version: "1.22"
-      - run: go build wowPing.go
-      - run: ./wowPing -n=2
+      - run: go build cmd/wow-ping/wow-ping.go
+      - run: go build cmd/wow-ping-service/wow-ping-service.go
+      - run: ./wow-ping -n=2

cmd/wow-ping-service/wow-ping-service.go

@@ -0,0 +1,98 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"time"
+
+	"github.com/egoroof/wow-server-ping-go/pkg/ping"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+)
+
+const port = 8090
+const sleepBetweenRequestsMs = 500
+
+var promRespTime = prometheus.NewGaugeVec(prometheus.GaugeOpts{
+	Name: "wow_server_response_time_ms",
+	Help: "WoW server response time in ms",
+}, []string{"server"})
+
+var promRespTimeout = prometheus.NewCounterVec(prometheus.CounterOpts{
+	Name: "wow_server_timeout_count",
+	Help: "WoW server timeout count",
+}, []string{"server"})
+
+var promRespErr = prometheus.NewCounterVec(prometheus.CounterOpts{
+	Name: "wow_server_error_count",
+	Help: "WoW server error count",
+}, []string{"server"})
+
+func recordMetrics() {
+	params := ping.ParseArguments(os.Args[1:])
+	responseChan := make(chan ping.ServerResponse)
+
+	for _, group := range ping.Servers {
+		if group.Name != params.ServerGroup {
+			continue
+		}
+
+		for _, server := range group.List {
+			promRespTimeout.WithLabelValues(server.Name).Add(0)
+			promRespErr.WithLabelValues(server.Name).Add(0)
+		}
+	}
+
+	for {
+		connectionCount := 0
+
+		for _, group := range ping.Servers {
+			if group.Name != params.ServerGroup {
+				continue
+			}
+
+			for _, server := range group.List {
+				connectionCount++
+				go ping.OpenConnection(server.Name, server.Host, server.Port, params.Timeout, responseChan)
+			}
+		}
+
+		for i := 0; i < connectionCount; i++ {
+			response := <-responseChan
+
+			if response.Error == nil {
+				promRespTime.WithLabelValues(response.Name).Set(float64(response.Duration))
+			} else {
+				promRespTime.DeleteLabelValues(response.Name)
+				if errors.Is(response.Error, context.DeadlineExceeded) || errors.Is(response.Error, os.ErrDeadlineExceeded) {
+					promRespTimeout.WithLabelValues(response.Name).Inc()
+				} else {
+					log.Printf("%v %v\n", response.Name, response.Error)
+					promRespErr.WithLabelValues(response.Name).Inc()
+				}
+			}
+		}
+
+		time.Sleep(time.Millisecond * sleepBetweenRequestsMs)
+	}
+}
+
+func main() {
+	promReg := prometheus.NewRegistry()
+	promReg.MustRegister(promRespTime)
+	promReg.MustRegister(promRespTimeout)
+	promReg.MustRegister(promRespErr)
+
+	handler := promhttp.HandlerFor(promReg, promhttp.HandlerOpts{})
+	http.Handle("/metrics", handler)
+
+	go recordMetrics()
+
+	log.Printf("Listening port %v\n", port)
+	err := http.ListenAndServe(fmt.Sprintf(":%v", port), nil)
+	log.Fatal(err)
+}

go.mod

@@ -1,3 +1,15 @@
 module github.com/egoroof/wow-server-ping-go
 
 go 1.22.1
+
+require github.com/prometheus/client_golang v1.19.0
+
+require (
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
+	github.com/prometheus/client_model v0.5.0 // indirect
+	github.com/prometheus/common v0.48.0 // indirect
+	github.com/prometheus/procfs v0.12.0 // indirect
+	golang.org/x/sys v0.16.0 // indirect
+	google.golang.org/protobuf v1.32.0 // indirect
+)

go.sum

@@ -0,0 +1,20 @@
+github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
+github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
+github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=
+github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
+github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/prometheus/client_golang v1.19.0 h1:ygXvpU1AoN1MhdzckN+PyD9QJOSD4x7kmXYlnfbA6JU=
+github.com/prometheus/client_golang v1.19.0/go.mod h1:ZRM9uEAypZakd+q/x7+gmsvXdURP+DABIEIjnmDdp+k=
+github.com/prometheus/client_model v0.5.0 h1:VQw1hfvPvk3Uv6Qf29VrPF32JB6rtbgI6cYPYQjL0Qw=
+github.com/prometheus/client_model v0.5.0/go.mod h1:dTiFglRmd66nLR9Pv9f0mZi7B7fk5Pm3gvsjB5tr+kI=
+github.com/prometheus/common v0.48.0 h1:QO8U2CdOzSn1BBsmXJXduaaW+dY/5QLjfB8svtSzKKE=
+github.com/prometheus/common v0.48.0/go.mod h1:0/KsvlIEfPQCQ5I2iNSAWKPZziNCvRs5EC6ILDTlAPc=
+github.com/prometheus/procfs v0.12.0 h1:jluTpSng7V9hY0O2R9DzzJHYb2xULk9VTR1V1R/k6Bo=
+github.com/prometheus/procfs v0.12.0/go.mod h1:pcuDEFsWDnvcgNzo4EEweacyhjeA9Zk3cnaOZAZEfOo=
+golang.org/x/sys v0.16.0 h1:xWw16ngr6ZMtmxDyKyIgsE93KNKz5HKmMa3b8ALHidU=
+golang.org/x/sys v0.16.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+google.golang.org/protobuf v1.32.0 h1:pPC6BG5ex8PDFnkbrGU3EixyhKcQ2aDuBS36lqK/C7I=
+google.golang.org/protobuf v1.32.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=