feature: add prometheus metrics (#268)

* feature: add prometheus metrics

* bugfix: ixed issue with path

cmd/OliveTin/main.go

@@ -8,6 +8,7 @@ import (
 	"github.com/OliveTin/OliveTin/internal/entityfiles"
 	"github.com/OliveTin/OliveTin/internal/executor"
 	grpcapi "github.com/OliveTin/OliveTin/internal/grpcapi"
+	"github.com/OliveTin/OliveTin/internal/httpservers"
 	"github.com/OliveTin/OliveTin/internal/installationinfo"
 	"github.com/OliveTin/OliveTin/internal/oncalendarfile"
 	"github.com/OliveTin/OliveTin/internal/oncron"
@@ -16,13 +17,10 @@ import (
 	updatecheck "github.com/OliveTin/OliveTin/internal/updatecheck"
 	"github.com/OliveTin/OliveTin/internal/websocket"
 
-	"github.com/OliveTin/OliveTin/internal/httpservers"
-
 	config "github.com/OliveTin/OliveTin/internal/config"
 	"github.com/fsnotify/fsnotify"
 	"github.com/spf13/viper"
 	"os"
-	"path"
 )
 
 var (
@@ -98,11 +96,11 @@ func initViperConfig(configDir string) {
 		if e.Op == fsnotify.Write {
 			log.Info("Config file changed:", e.String())
 
-			reloadConfig()
+			config.Reload(cfg)
 		}
 	})
 
-	reloadConfig()
+	config.Reload(cfg)
 }
 
 func initInstallationInfo() {
@@ -130,16 +128,6 @@ func warnIfPuidGuid() {
 	}
 }
 
-func reloadConfig() {
-	if err := viper.UnmarshalExact(&cfg); err != nil {
-		log.Errorf("Config unmarshal error %+v", err)
-		os.Exit(1)
-	}
-
-	cfg.SetDir(path.Dir(viper.ConfigFileUsed()))
-	cfg.Sanitize()
-}
-
 func main() {
 	log.WithFields(log.Fields{
 		"configDir": cfg.GetDir(),

go.mod

@@ -14,6 +14,7 @@ require (
 	github.com/google/uuid v1.6.0
 	github.com/gorilla/websocket v1.4.1
 	github.com/grpc-ecosystem/grpc-gateway/v2 v2.19.1
+	github.com/prometheus/client_golang v1.19.0
 	github.com/robfig/cron/v3 v3.0.1
 	github.com/sirupsen/logrus v1.9.3
 	github.com/spf13/viper v1.15.0
@@ -33,10 +34,12 @@ require (
 	github.com/Azure/go-ansiterm v0.0.0-20230124172434-306776ec8161 // indirect
 	github.com/Microsoft/go-winio v0.6.1 // indirect
 	github.com/antlr4-go/antlr/v4 v4.13.0 // indirect
+	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/bufbuild/protocompile v0.9.0 // indirect
 	github.com/bufbuild/protovalidate-go v0.6.0 // indirect
 	github.com/bufbuild/protoyaml-go v0.1.8 // indirect
 	github.com/cenkalti/backoff/v4 v4.2.1 // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
 	github.com/containerd/stargz-snapshotter/estargz v0.15.1 // indirect
 	github.com/cpuguy83/go-md2man/v2 v2.0.4 // indirect
 	github.com/cristalhq/acmd v0.11.2 // indirect
@@ -87,11 +90,13 @@ require (
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pkg/profile v1.7.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // 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
 	github.com/quasilyte/go-ruleguard v0.4.2 // indirect
 	github.com/quasilyte/gogrep v0.5.0 // indirect
 	github.com/quasilyte/regex/syntax v0.0.0-20210819130434-b3f0c404a727 // indirect
 	github.com/quasilyte/stdinfo v0.0.0-20220114132959-f7386bf02567 // indirect
-	github.com/rogpeppe/go-internal v1.10.0 // indirect
 	github.com/rs/cors v1.10.1 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
 	github.com/spf13/afero v1.9.3 // indirect

go.sum

@@ -50,6 +50,8 @@ github.com/Microsoft/go-winio v0.6.1 h1:9/kr64B9VUZrLm5YYwbGtUJnMgqWVOdUAXu6Migc
 github.com/Microsoft/go-winio v0.6.1/go.mod h1:LRdKpFKfdobln8UmuiYcKPot9D2v6svN5+sAH+4kjUM=
 github.com/antlr4-go/antlr/v4 v4.13.0 h1:lxCg3LAv+EUK6t1i0y1V6/SLeUi0eKEKdhQAlS8TVTI=
 github.com/antlr4-go/antlr/v4 v4.13.0/go.mod h1:pfChB/xh/Unjila75QW7+VU4TSnWnnk9UTnmpPaOR2g=
+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/bufbuild/buf v1.30.1 h1:QFtanwsXodoGFAwzXFXGXpzBkb7N2u8ZDyA3jWB4Pbs=
 github.com/bufbuild/buf v1.30.1/go.mod h1:7W8DJnj76wQa55EA3z2CmDxS0/nsHh8FqtE00dyDAdA=
 github.com/bufbuild/protocompile v0.9.0 h1:DI8qLG5PEO0Mu1Oj51YFPqtx6I3qYXUAhJVJ/IzAVl0=
@@ -61,6 +63,8 @@ github.com/bufbuild/protoyaml-go v0.1.8/go.mod h1:R8vE2+l49bSiIExP4VJpxOXleHE+FD
 github.com/cenkalti/backoff/v4 v4.2.1 h1:y4OZtCnogmCPw98Zjyt5a6+QwPLGkiQsYW5oUqylYbM=
 github.com/cenkalti/backoff/v4 v4.2.1/go.mod h1:Y3VNntkOUPxTVeUxJ/G5vcM//AlwfmyYozVcomhLiZE=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
+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/chromedp/cdproto v0.0.0-20230802225258-3cf4e6d46a89/go.mod h1:GKljq0VrfU4D5yc+2qA6OVr8pmO/MBbPEWqWQ/oqGEs=
 github.com/chromedp/chromedp v0.9.2/go.mod h1:LkSXJKONWTCHAfQasKFUZI+mxqS4tZqhmtGzzhLsnLs=
 github.com/chromedp/sysutil v1.0.0/go.mod h1:kgWmDdq8fTzXYcKIBqIYvRRTnYb9aNS9moAV0xufSww=
@@ -304,7 +308,15 @@ github.com/pkg/profile v1.7.0/go.mod h1:8Uer0jas47ZQMJ7VD+OHknK4YDY07LPUC6dEvqDj
 github.com/pkg/sftp v1.13.1/go.mod h1:3HaPG6Dq1ILlpPZRO0HVMrsydcdLt6HRDccSgb87qRg=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+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 v0.0.0-20190812154241-14fe0d1b01d4/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
+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=
 github.com/quasilyte/go-ruleguard v0.4.2 h1:htXcXDK6/rO12kiTHKfHuqR4kr3Y4M0J0rOL6CH/BYs=
 github.com/quasilyte/go-ruleguard v0.4.2/go.mod h1:GJLgqsLeo4qgavUoL8JeGFNS7qcisx3awV/w9eWTmNI=
 github.com/quasilyte/gogrep v0.5.0 h1:eTKODPXbI8ffJMN+W2aE0+oL0z/nh8/5eNdiO34SOAo=

internal/config/config.go

@@ -64,6 +64,11 @@ type AccessControlList struct {
 	Permissions      PermissionsList
 }
 
+type PrometheusConfig struct {
+	Enabled          bool
+	DefaultGoMetrics bool
+}
+
 // Config is the global config used through the whole app.
 type Config struct {
 	UseSingleHTTPFrontend           bool
@@ -72,6 +77,7 @@ type Config struct {
 	ListenAddressWebUI              string
 	ListenAddressRestActions        string
 	ListenAddressGrpcActions        string
+	ListenAddressPrometheus         string
 	ExternalRestAddress             string
 	LogLevel                        string
 	LogDebugOptions                 LogDebugOptions
@@ -103,6 +109,7 @@ type Config struct {
 	InsecureAllowDumpVars           bool
 	InsecureAllowDumpSos            bool
 	InsecureAllowDumpActionMap      bool
+	Prometheus                      PrometheusConfig
 
 	usedConfigDir string
 }
@@ -131,6 +138,7 @@ func DefaultConfig() *Config {
 	config.ListenAddressRestActions = "localhost:1338"
 	config.ListenAddressGrpcActions = "localhost:1339"
 	config.ListenAddressWebUI = "localhost:1340"
+	config.ListenAddressPrometheus = "localhost:1341"
 	config.ExternalRestAddress = "."
 	config.LogLevel = "INFO"
 	config.CheckForUpdates = true
@@ -145,6 +153,8 @@ func DefaultConfig() *Config {
 	config.InsecureAllowDumpVars = false
 	config.InsecureAllowDumpSos = false
 	config.InsecureAllowDumpActionMap = false
+	config.Prometheus.Enabled = false
+	config.Prometheus.DefaultGoMetrics = false
 
 	return &config
 }

internal/config/config_reloader.go

@@ -0,0 +1,37 @@
+package config
+
+import (
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
+
+	log "github.com/sirupsen/logrus"
+	"os"
+	"path"
+
+	"github.com/spf13/viper"
+)
+
+var (
+	metricConfigActionCount = promauto.NewGauge(prometheus.GaugeOpts{
+		Name: "olivetin_config_action_count",
+		Help: "Then number of actions in the config file",
+	})
+
+	metricConfigReloadedCount = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "olivetin_config_reloaded_count",
+		Help: "The number of times the config has been reloaded",
+	})
+)
+
+func Reload(cfg *Config) {
+	if err := viper.UnmarshalExact(&cfg); err != nil {
+		log.Errorf("Config unmarshal error %+v", err)
+		os.Exit(1)
+	}
+
+	metricConfigReloadedCount.Inc()
+	metricConfigActionCount.Set(float64(len(cfg.Actions)))
+
+	cfg.SetDir(path.Dir(viper.ConfigFileUsed()))
+	cfg.Sanitize()
+}

internal/entityfiles/entityfiles.go

@@ -174,13 +174,13 @@ func updateEvmFromFile(entityname string, data []map[string]string) {
 
 	sv.RemoveKeysThatStartWith("entities." + entityname)
 
-	sv.Contents["entities."+entityname+".count"] = fmt.Sprintf("%v", count)
+	sv.Set("entities."+entityname+".count", fmt.Sprintf("%v", count))
 
 	for i, mapp := range data {
 		prefix := "entities." + entityname + "." + fmt.Sprintf("%v", i)
 
 		for k, v := range mapp {
-			sv.Contents[prefix+"."+k] = v
+			sv.Set(prefix+"."+k, v)
 		}
 	}
 }

internal/executor/executor.go

@@ -7,6 +7,9 @@ import (
 	"github.com/google/uuid"
 	log "github.com/sirupsen/logrus"
 
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
+
 	"bytes"
 	"context"
 	"fmt"
@@ -17,6 +20,13 @@ import (
 	"time"
 )
 
+var (
+	metricActionsRequested = promauto.NewGauge(prometheus.GaugeOpts{
+		Name: "olivetin_actions_requested_count",
+		Help: "The actions requested count",
+	})
+)
+
 // Executor represents a helper class for executing commands. It's main method
 // is ExecRequest
 type Executor struct {
@@ -229,6 +239,8 @@ func stepRequestAction(req *ExecutionRequest) bool {
 		}
 	}
 
+	metricActionsRequested.Inc()
+
 	req.logEntry.ActionTitle = sv.ReplaceEntityVars(req.EntityPrefix, req.Action.Title)
 	req.logEntry.ActionIcon = req.Action.Icon
 	req.logEntry.ActionId = req.Action.ID

internal/grpcapi/grpcApi.go

@@ -302,7 +302,7 @@ func (api *oliveTinAPI) DumpVars(ctx ctx.Context, req *pb.DumpVarsRequest) (*pb.
 	}
 
 	res.Alert = "Dumping variables has been enabled in the configuration. Please set InsecureAllowDumpVars = false again after you don't need it anymore"
-	res.Contents = sv.Contents
+	res.Contents = sv.GetAll()
 
 	return res, nil
 }

internal/httpservers/httpServer.go

@@ -13,5 +13,9 @@ func StartServers(cfg *config.Config) {
 		go StartSingleHTTPFrontend(cfg)
 	}
 
+	if cfg.Prometheus.Enabled {
+		go StartPrometheus(cfg)
+	}
+
 	startRestAPIServer(cfg)
 }

internal/httpservers/prometheus.go

@@ -0,0 +1,19 @@
+package httpservers
+
+import (
+	"net/http"
+
+	config "github.com/OliveTin/OliveTin/internal/config"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/collectors"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+)
+
+func StartPrometheus(cfg *config.Config) {
+	if !cfg.Prometheus.DefaultGoMetrics {
+		prometheus.Unregister(collectors.NewGoCollector())
+	}
+
+	http.Handle("/", promhttp.Handler())
+	http.ListenAndServe(cfg.ListenAddressPrometheus, nil)
+}

internal/httpservers/singleFrontend.go

@@ -62,6 +62,16 @@ func StartSingleHTTPFrontend(cfg *config.Config) {
 		webuiProxy.ServeHTTP(w, r)
 	})
 
+	if cfg.Prometheus.Enabled {
+		promURL, _ := url.Parse("http://" + cfg.ListenAddressPrometheus)
+		promProxy := httputil.NewSingleHostReverseProxy(promURL)
+
+		mux.HandleFunc("/metrics", func(w http.ResponseWriter, r *http.Request) {
+			log.Debugf("prom req: %q", r.URL)
+			promProxy.ServeHTTP(w, r)
+		})
+	}
+
 	srv := &http.Server{
 		Addr:    cfg.ListenAddressSingleHTTPFrontend,
 		Handler: mux,

internal/installationinfo/init.go

@@ -6,11 +6,11 @@ import (
 )
 
 func init() {
-	sv.Contents["OliveTin.build.commit"] = Build.Commit
-	sv.Contents["OliveTin.build.version"] = Build.Version
-	sv.Contents["OliveTin.build.date"] = Build.Date
-	sv.Contents["OliveTin.runtime.os"] = Runtime.OS
-	sv.Contents["OliveTin.runtime.os.pretty"] = Runtime.OSReleasePrettyName
-	sv.Contents["OliveTin.runtime.arch"] = Runtime.Arch
-	sv.Contents["OliveTin.runtime.incontainer"] = fmt.Sprintf("%v", Runtime.InContainer)
+	sv.Set("OliveTin.build.commit", Build.Commit)
+	sv.Set("OliveTin.build.version", Build.Version)
+	sv.Set("OliveTin.build.date", Build.Date)
+	sv.Set("OliveTin.runtime.os", Runtime.OS)
+	sv.Set("OliveTin.runtime.os.pretty", Runtime.OSReleasePrettyName)
+	sv.Set("OliveTin.runtime.arch", Runtime.Arch)
+	sv.Set("OliveTin.runtime.incontainer", fmt.Sprintf("%v", Runtime.InContainer))
 }

internal/stringvariables/entities.go

@@ -31,9 +31,9 @@ func ReplaceEntityVars(prefix string, source string) string {
 }
 
 func RemoveKeysThatStartWith(search string) {
-	for k, _ := range Contents {
+	for k, _ := range contents {
 		if strings.HasPrefix(k, search) {
-			delete(Contents, k)
+			delete(contents, k)
 		}
 	}
 }

internal/stringvariables/map.go

@@ -9,14 +9,26 @@
 
 package stringvariables
 
-var Contents map[string]string
+import (
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
+)
+
+var (
+	contents map[string]string
+
+	metricSvCount = promauto.NewGauge(prometheus.GaugeOpts{
+		Name: "olivetin_sv_count",
+		Help: "The number entries in the sv map",
+	})
+)
 
 func init() {
-	Contents = make(map[string]string)
+	contents = make(map[string]string)
 }
 
 func Get(key string) string {
-	v, ok := Contents[key]
+	v, ok := contents[key]
 
 	if !ok {
 		return ""
@@ -24,3 +36,13 @@ func Get(key string) string {
 		return v
 	}
 }
+
+func GetAll() map[string]string {
+	return contents
+}
+
+func Set(key string, value string) {
+	contents[key] = value
+
+	metricSvCount.Set(float64(len(contents)))
+}