packages/hyprspace: enable optional prometheus metrics endpoint

packages/networking/hyprspace/cli/up.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"io/fs"
 	"net"
+	"net/http"
 	"os"
 	"os/signal"
 	"path/filepath"
@@ -26,6 +27,7 @@ import (
 	"github.com/libp2p/go-libp2p/core/peer"
 	"github.com/multiformats/go-multiaddr"
 	"github.com/multiformats/go-multibase"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 )
 
 var (
@@ -140,6 +142,17 @@ func UpRun(r *cmd.Root, c *cmd.Sub) {
 	// RPC server
 	go hsrpc.RpcServer(ctx, multiaddr.StringCast(fmt.Sprintf("/unix/run/hyprspace-rpc.%s.sock", cfg.Interface.Name)), host, *cfg)
 
+	// metrics endpoint
+	metricsPort, ok := os.LookupEnv("HYPRSPACE_METRICS_PORT")
+	if ok {
+		metricsTuple := fmt.Sprintf("127.0.0.1:%s", metricsPort)
+		http.Handle("/metrics", promhttp.Handler())
+		go func() {
+			http.ListenAndServe(metricsTuple, nil)
+		}()
+		fmt.Printf("[+] Listening for metrics scrape requests on http://%s/metrics\n", metricsTuple)
+	}
+
 	// Write lock to filesystem to indicate an existing running daemon.
 	err = os.WriteFile(lockPath, []byte(fmt.Sprint(os.Getpid())), os.ModePerm)
 	checkErr(err)

packages/networking/hyprspace/go.mod

@@ -8,6 +8,7 @@ require (
 	github.com/libp2p/go-libp2p-kad-dht v0.25.0
 	github.com/multiformats/go-multiaddr v0.11.0
 	github.com/multiformats/go-multibase v0.2.0
+	github.com/prometheus/client_golang v1.16.0
 	github.com/songgao/water v0.0.0-20200317203138-2b4b6d7c09d8
 	github.com/vishvananda/netlink v1.1.0
 	gopkg.in/yaml.v2 v2.4.0
@@ -87,7 +88,6 @@ require (
 	github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/polydawn/refmt v0.89.0 // indirect
-	github.com/prometheus/client_golang v1.16.0 // indirect
 	github.com/prometheus/client_model v0.4.0 // indirect
 	github.com/prometheus/common v0.44.0 // indirect
 	github.com/prometheus/procfs v0.11.1 // indirect