Added optional metrics gathering via Prometheus client.

cmd/eps/main.go

@@ -20,15 +20,13 @@ import (
 	"github.com/iris-connect/eps"
 	"github.com/iris-connect/eps/cmd/helpers"
 	"github.com/iris-connect/eps/definitions"
-	"github.com/iris-connect/eps/metrics"
 )
 
 func main() {
 	if settings, err := helpers.Settings(&definitions.Default); err != nil {
 		eps.Log.Error(err)
 		return
 	} else {
-		metrics.OpenPrometheusEndpoint()
 		helpers.CLI(settings)
 	}
 }

cmd/helpers/server.go

@@ -19,6 +19,7 @@ package helpers
 import (
 	"github.com/iris-connect/eps"
 	"github.com/iris-connect/eps/helpers"
+	"github.com/iris-connect/eps/metrics"
 	"github.com/urfave/cli"
 	"os"
 	"os/signal"
@@ -83,6 +84,8 @@ func Server(settings *eps.Settings) ([]cli.Command, error) {
 						sigchan := make(chan os.Signal, 1)
 						signal.Notify(sigchan, syscall.SIGINT, syscall.SIGTERM)
 
+						metricsServer := metrics.MakePrometheusMetricsServer(settings.Metrics)
+
 						eps.Log.Info("Waiting for CTRL-C...")
 
 						<-sigchan
@@ -91,6 +94,12 @@ func Server(settings *eps.Settings) ([]cli.Command, error) {
 
 						closeChannels(channels)
 
+						if metricsServer != nil {
+							if err := metricsServer.Stop(); err != nil {
+								eps.Log.Error(err)
+							}
+						}
+
 						return nil
 					},
 				},

cmd/proxy/main.go

@@ -98,6 +98,8 @@ func CLI(settings *proxy.Settings) {
 							eps.Log.Fatal(err)
 						}
 
+						metricsServer := metrics.MakePrometheusMetricsServer(settings.Metrics)
+
 						// we wait for CTRL-C / Interrupt
 						sigchan := make(chan os.Signal, 1)
 						signal.Notify(sigchan, syscall.SIGINT, syscall.SIGTERM)
@@ -112,6 +114,12 @@ func CLI(settings *proxy.Settings) {
 							eps.Log.Fatal(err)
 						}
 
+						if metricsServer != nil {
+							if err := metricsServer.Stop(); err != nil {
+								eps.Log.Fatal(err)
+							}
+						}
+
 						return nil
 					},
 				},
@@ -136,6 +144,8 @@ func CLI(settings *proxy.Settings) {
 							eps.Log.Fatal(err)
 						}
 
+						metricsServer := metrics.MakePrometheusMetricsServer(settings.Metrics)
+
 						// we wait for CTRL-C / Interrupt
 						sigchan := make(chan os.Signal, 1)
 						signal.Notify(sigchan, syscall.SIGINT, syscall.SIGTERM)
@@ -150,6 +160,12 @@ func CLI(settings *proxy.Settings) {
 							eps.Log.Fatal(err)
 						}
 
+						if metricsServer != nil {
+							if err := metricsServer.Stop(); err != nil {
+								eps.Log.Fatal(err)
+							}
+						}
+
 						return nil
 					},
 				},
@@ -172,7 +188,6 @@ func main() {
 		eps.Log.Error(err)
 		return
 	} else {
-		metrics.OpenPrometheusEndpoint()
 		CLI(settings)
 	}
 }

cmd/sd/main.go

@@ -89,6 +89,8 @@ func CLI(settings *sd.Settings) {
 					eps.Log.Fatal(err)
 				}
 
+				metricsServer := metrics.MakePrometheusMetricsServer(settings.Metrics)
+
 				// we wait for CTRL-C / Interrupt
 				sigchan := make(chan os.Signal, 1)
 				signal.Notify(sigchan, syscall.SIGINT, syscall.SIGTERM)
@@ -103,6 +105,12 @@ func CLI(settings *sd.Settings) {
 					eps.Log.Fatal(err)
 				}
 
+				if metricsServer != nil {
+					if err := metricsServer.Stop(); err != nil {
+						eps.Log.Fatal(err)
+					}
+				}
+
 				return nil
 			},
 		},
@@ -123,7 +131,6 @@ func main() {
 		eps.Log.Error(err)
 		return
 	} else {
-		metrics.OpenPrometheusEndpoint()
 		CLI(settings)
 	}
 }

examples/eps-ls/ls.go

@@ -101,7 +101,6 @@ func main() {
 	if server, err := jsonrpc.MakeJSONRPCServer(settings, handler); err != nil {
 		eps.Log.Fatal(err)
 	} else {
-		metrics.OpenPrometheusEndpoint()
 		server.Start()
 
 		// we wait for CTRL-C / Interrupt

examples/internal-server/server.go

@@ -103,7 +103,6 @@ func main() {
 	if server, err := http.MakeHTTPServer(settings, routeGroups); err != nil {
 		eps.Log.Fatal(err)
 	} else {
-		metrics.OpenPrometheusEndpoint()
 		server.Start()
 
 		// we wait for CTRL-C / Interrupt

forms/settings.go

@@ -64,6 +64,17 @@ var ChannelForm = forms.Form{
 	},
 }
 
+var MetricsSettingsForm = forms.Form{
+	Fields: []forms.Field{
+		{
+			Name: "bind_address",
+			Validators: []forms.Validator{
+				forms.IsString{},
+			},
+		},
+	},
+}
+
 var SettingsForm = forms.Form{
 	Fields: []forms.Field{
 		{
@@ -80,6 +91,15 @@ var SettingsForm = forms.Form{
 				},
 			},
 		},
+		{
+			Name: "metrics",
+			Validators: []forms.Validator{
+				forms.IsOptional{},
+				forms.IsStringMap{
+					Form: &MetricsSettingsForm,
+				},
+			},
+		},
 		{
 			Name: "signing",
 			Validators: []forms.Validator{

go.sum

@@ -108,6 +108,7 @@ github.com/prometheus/procfs v0.0.2/go.mod h1:TjEm7ze935MbeOT/UhFTIMYKhuLP4wbCsT
 github.com/prometheus/procfs v0.1.3/go.mod h1:lV6e/gmhEcM9IjHGsFOCxxuZ+z1YqCvr4OA4YeYWdaU=
 github.com/prometheus/procfs v0.6.0 h1:mxy4L2jP6qMonqmq+aTtOx1ifVWUgG/TAmntgbh3xv4=
 github.com/prometheus/procfs v0.6.0/go.mod h1:cz+aTbrPOrUb4q7XlbU9ygM+/jj0fzG6c1xBZuNvfVA=
+github.com/protocolbuffers/protobuf v3.15.8+incompatible/go.mod h1:DdhgU1nye99PVSHQwKVPGBaTs902wvndr/KhlFhJxmw=
 github.com/russross/blackfriday/v2 v2.0.1 h1:lPqVAte+HuHNfhJ/0LC98ESWRz8afy9tM/0RK8m9o+Q=
 github.com/russross/blackfriday/v2 v2.0.1/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/shurcooL/sanitized_anchor_name v1.0.0 h1:PdmoCO6wvbs+7yrJyMORt4/BmY5IYyJwS/kOiWx8mHo=
@@ -189,6 +190,7 @@ google.golang.org/grpc v1.25.1/go.mod h1:c3i+UQWmh7LiEpx4sFZnkU36qjEYZ0imhYfXVyQ
 google.golang.org/grpc v1.27.0/go.mod h1:qbnxyOmOxrQa7FizSgH+ReBfzJrCY1pSN7KXBS8abTk=
 google.golang.org/grpc v1.37.0 h1:uSZWeQJX5j11bIQ4AJoj+McDBo29cY1MCoC1wO3ts+c=
 google.golang.org/grpc v1.37.0/go.mod h1:NREThFqKR1f3iQ6oBuvc5LadQuXVGo9rkm5ZGrQdJfM=
+google.golang.org/grpc/cmd/protoc-gen-go-grpc v1.1.0/go.mod h1:6Kw0yEErY5E/yWrBtf03jp27GLLJujG4z/JK95pnjjw=
 google.golang.org/protobuf v0.0.0-20200109180630-ec00e32a8dfd/go.mod h1:DFci5gLYBciE7Vtevhsrf46CRTquxDuWsQurQQe4oz8=
 google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ01Woi6D6+Kah6886xMZcty6N08ah7+eCXa0=
 google.golang.org/protobuf v0.0.0-20200228230310-ab0ca4ff8a60/go.mod h1:cfTl7dwQJ+fmap5saPgwCLgHXTUD7jkjRqWcaiX5VyM=

metrics/metrics.go

@@ -1,29 +1,47 @@
 package metrics
 
 import (
-	"fmt"
+	"context"
 	"github.com/iris-connect/eps"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"net/http"
-	"os"
+	"time"
 )
 
-const (
-	prometheusPort = 2112
-	prometheusPath = "/metrics"
-)
+type PrometheusMetricsServer struct {
+	server *http.Server
+}
+
+func MakePrometheusMetricsServer(settings *eps.MetricsSettings) *PrometheusMetricsServer {
 
-func OpenPrometheusEndpoint() {
-	if os.Getenv("METRICS_ENABLED") != "true" {
-		return
+	if settings == nil {
+		return nil
 	}
 
+	p := &PrometheusMetricsServer{
+		server: &http.Server{Addr: settings.BindAddress, Handler: promhttp.Handler()},
+	}
+
+	eps.Log.Infof("Serving metrics on %s...", settings.BindAddress)
+
 	go func() {
-		eps.Log.Infof("Starting Prometheus listener at http://localhost:%d%s", prometheusPort, prometheusPath)
-		http.Handle(prometheusPath, promhttp.Handler())
-		err := http.ListenAndServe(fmt.Sprintf(":%d", prometheusPort), nil)
-		if err != nil {
-			eps.Log.Error("Could not open prometheus endpoint: ", err)
+		if err := p.server.ListenAndServe(); err != nil {
+			if err != http.ErrServerClosed {
+				eps.Log.Error(err)
+			}
 		}
 	}()
+
+	return p
+}
+
+func (p *PrometheusMetricsServer) Stop() error {
+
+	eps.Log.Info("Shutting down Prometheus metrics server...")
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+	return p.server.Shutdown(ctx)
+
+	return nil
 }

proxy/forms.go

@@ -18,6 +18,7 @@ package proxy
 
 import (
 	"fmt"
+	epsForms "github.com/iris-connect/eps/forms"
 	"github.com/iris-connect/eps/jsonrpc"
 	"github.com/iris-connect/eps/tls"
 	"github.com/kiprotect/go-helpers/forms"
@@ -41,6 +42,15 @@ var DirectorySettingsForm = forms.Form{
 
 var SettingsForm = forms.Form{
 	Fields: []forms.Field{
+		{
+			Name: "metrics",
+			Validators: []forms.Validator{
+				forms.IsOptional{},
+				forms.IsStringMap{
+					Form: &epsForms.MetricsSettingsForm,
+				},
+			},
+		},
 		{
 			Name: "public",
 			Validators: []forms.Validator{

proxy/settings.go

@@ -17,6 +17,7 @@
 package proxy
 
 import (
+	"github.com/iris-connect/eps"
 	"github.com/iris-connect/eps/jsonrpc"
 	"github.com/iris-connect/eps/tls"
 	"time"
@@ -28,6 +29,7 @@ const (
 )
 
 type Settings struct {
+	Metrics *eps.MetricsSettings   `json:"metrics"`
 	Private *PrivateServerSettings `json:"private"`
 	Public  *PublicServerSettings  `json:"public"`
 }

sd/forms.go

@@ -17,12 +17,22 @@
 package sd
 
 import (
+	epsForms "github.com/iris-connect/eps/forms"
 	"github.com/iris-connect/eps/jsonrpc"
 	"github.com/kiprotect/go-helpers/forms"
 )
 
 var RecordDirectorySettingsForm = forms.Form{
 	Fields: []forms.Field{
+		{
+			Name: "metrics",
+			Validators: []forms.Validator{
+				forms.IsOptional{},
+				forms.IsStringMap{
+					Form: &epsForms.MetricsSettingsForm,
+				},
+			},
+		},
 		{
 			Name: "ca_certificate_files",
 			Validators: []forms.Validator{

sd/settings.go

@@ -17,10 +17,12 @@
 package sd
 
 import (
+	"github.com/iris-connect/eps"
 	"github.com/iris-connect/eps/jsonrpc"
 )
 
 type Settings struct {
+	Metrics       *eps.MetricsSettings           `json:"metrics"`
 	JSONRPCServer *jsonrpc.JSONRPCServerSettings `json:"jsonrpc_server`
 	Directory     *RecordDirectorySettings       `json:"directory"`
 }

settings.go

@@ -36,11 +36,16 @@ type SigningSettings struct {
 	KeyFile                        string   `json:"key_file"`
 }
 
+type MetricsSettings struct {
+	BindAddress string `json:"bind_address"`
+}
+
 type Settings struct {
 	Signing     *SigningSettings   `json:"signing"`
 	Definitions *Definitions       `json:"definitions"`
 	Channels    []*ChannelSettings `json:"channels"`
 	Directory   *DirectorySettings `json:"directory"`
+	Metrics     *MetricsSettings   `json:"metrics"`
 	Name        string             `json:"name"`
 }
 

settings/dev/roles/hd-1/001_default.yml

@@ -1,4 +1,6 @@
 name: hd-1
+metrics:
+  bind_address: "localhost:2112"
 directory:
 # to use the JSON directory, uncomment this and comment everything below...
 #  type: json