add Prometheus support

some basic counters and gauges are now exposed

README.md

@@ -19,6 +19,7 @@ Full featured and highly configurable SFTP server
 - Atomic uploads are configurable.
 - Optional SCP support.
 - REST API for users and quota management and real time reports for the active connections with possibility of forcibly closing a connection.
+- Prometheus metrics are exposed.
 - Configuration is a your choice: JSON, TOML, YAML, HCL, envfile are supported.
 - Log files are accurate and they are saved in the easily parsable JSON format.
 
@@ -289,6 +290,23 @@ A sample CLI client for the REST API can be found inside the source tree [script
 
 You can also generate your own REST client, in your preferred programming language or even bash scripts, using an OpenAPI generator such as [swagger-codegen](https://github.com/swagger-api/swagger-codegen) or [OpenAPI Generator](https://openapi-generator.tech/)
 
+## Metrics
+
+SFTPGo exposes [Prometheus](https://prometheus.io/) metrics at the `/metrics` HTTP endpoint.
+Several counters and gauges are available, for example:
+
+- Total uploads and downloads
+- Total uploads and downloads size
+- Total uploads and downloads errors
+- Number of active connections
+- Data provider availability
+- Total successful and failed logins using a password or a public key
+- Total HTTP requests served and totals for response code
+- Go's runtime like details about GC, number of gouroutines and OS threads
+- Process information like CPU, memory, file descriptor usage and start time
+
+Please check the `/metrics` page for more details.
+
 ## Logs
 
 Inside the log file each line is a JSON struct, each struct has a `sender` fields that identify the log type.

api/api.go

@@ -19,6 +19,7 @@ const (
 	quotaScanPath         = "/api/v1/quota_scan"
 	userPath              = "/api/v1/user"
 	versionPath           = "/api/v1/version"
+	metricsPath           = "/metrics"
 )
 
 var (

api/api_test.go

@@ -36,6 +36,7 @@ const (
 	activeConnectionsPath = "/api/v1/connection"
 	quotaScanPath         = "/api/v1/quota_scan"
 	versionPath           = "/api/v1/version"
+	metricsPath           = "/metrics"
 )
 
 var (
@@ -710,6 +711,12 @@ func TestMethodNotAllowedMock(t *testing.T) {
 	checkResponseCode(t, http.StatusMethodNotAllowed, rr.Code)
 }
 
+func TestMetricsMock(t *testing.T) {
+	req, _ := http.NewRequest(http.MethodGet, metricsPath, nil)
+	rr := executeRequest(req)
+	checkResponseCode(t, http.StatusOK, rr.Code)
+}
+
 func waitTCPListening(address string) {
 	for {
 		conn, err := net.Dial("tcp", address)

api/router.go

@@ -9,6 +9,7 @@ import (
 	"github.com/go-chi/chi"
 	"github.com/go-chi/chi/middleware"
 	"github.com/go-chi/render"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 )
 
 // GetHTTPRouter returns the configured HTTP handler
@@ -31,6 +32,8 @@ func initializeRouter() {
 		sendAPIResponse(w, r, nil, "Method not allowed", http.StatusMethodNotAllowed)
 	}))
 
+	router.Handle(metricsPath, promhttp.Handler())
+
 	router.Get(versionPath, func(w http.ResponseWriter, r *http.Request) {
 		render.JSON(w, r, utils.GetAppVersion())
 	})

dataprovider/bolt.go

@@ -59,6 +59,11 @@ func initializeBoltProvider(basePath string) error {
 	return err
 }
 
+func (p BoltProvider) checkAvailability() error {
+	_, err := p.getUsers(1, 0, "ASC", "")
+	return err
+}
+
 func (p BoltProvider) validateUserAndPass(username string, password string) (User, error) {
 	var user User
 	if len(password) == 0 {

dataprovider/dataprovider.go

@@ -15,6 +15,7 @@ import (
 	"path/filepath"
 	"strconv"
 	"strings"
+	"time"
 
 	"github.com/alexedwards/argon2id"
 	"golang.org/x/crypto/bcrypt"
@@ -22,6 +23,7 @@ import (
 	"golang.org/x/crypto/ssh"
 
 	"github.com/drakkan/sftpgo/logger"
+	"github.com/drakkan/sftpgo/metrics"
 	"github.com/drakkan/sftpgo/utils"
 )
 
@@ -52,9 +54,10 @@ var (
 	sqlPlaceholders    []string
 	validPerms         = []string{PermAny, PermListItems, PermDownload, PermUpload, PermDelete, PermRename,
 		PermCreateDirs, PermCreateSymlinks}
-	hashPwdPrefixes  = []string{argonPwdPrefix, bcryptPwdPrefix, pbkdf2SHA1Prefix, pbkdf2SHA256Prefix, pbkdf2SHA512Prefix}
-	pbkdfPwdPrefixes = []string{pbkdf2SHA1Prefix, pbkdf2SHA256Prefix, pbkdf2SHA512Prefix}
-	logSender        = "dataProvider"
+	hashPwdPrefixes    = []string{argonPwdPrefix, bcryptPwdPrefix, pbkdf2SHA1Prefix, pbkdf2SHA256Prefix, pbkdf2SHA512Prefix}
+	pbkdfPwdPrefixes   = []string{pbkdf2SHA1Prefix, pbkdf2SHA256Prefix, pbkdf2SHA512Prefix}
+	logSender          = "dataProvider"
+	availabilityTicker *time.Ticker
 )
 
 // Config provider configuration
@@ -144,23 +147,34 @@ type Provider interface {
 	deleteUser(user User) error
 	getUsers(limit int, offset int, order string, username string) ([]User, error)
 	getUserByID(ID int64) (User, error)
+	checkAvailability() error
+}
+
+func init() {
+	availabilityTicker = time.NewTicker(30 * time.Second)
 }
 
 // Initialize the data provider.
 // An error is returned if the configured driver is invalid or if the data provider cannot be initialized
 func Initialize(cnf Config, basePath string) error {
+	var err error
 	config = cnf
 	sqlPlaceholders = getSQLPlaceholders()
 	if config.Driver == SQLiteDataProviderName {
-		return initializeSQLiteProvider(basePath)
+		err = initializeSQLiteProvider(basePath)
 	} else if config.Driver == PGSQLDataProviderName {
-		return initializePGSQLProvider()
+		err = initializePGSQLProvider()
 	} else if config.Driver == MySQLDataProviderName {
-		return initializeMySQLProvider()
+		err = initializeMySQLProvider()
 	} else if config.Driver == BoltDataProviderName {
-		return initializeBoltProvider(basePath)
+		err = initializeBoltProvider(basePath)
+	} else {
+		err = fmt.Errorf("Unsupported data provider: %v", config.Driver)
+	}
+	if err == nil {
+		startAvailabilityTimer()
 	}
-	return fmt.Errorf("Unsupported data provider: %v", config.Driver)
+	return err
 }
 
 // CheckUserAndPass retrieves the SFTP user with the given username and password if a match is found or an error
@@ -374,6 +388,23 @@ func getSSLMode() string {
 	return ""
 }
 
+func startAvailabilityTimer() {
+	checkDataprovider()
+	go func() {
+		for range availabilityTicker.C {
+			checkDataprovider()
+		}
+	}()
+}
+
+func checkDataprovider() {
+	err := provider.checkAvailability()
+	if err != nil {
+		providerLog(logger.LevelWarn, "check availability error: %v", err)
+	}
+	metrics.UpdateDataProviderAvailability(err)
+}
+
 func providerLog(level logger.LogLevel, format string, v ...interface{}) {
 	logger.Log(level, logSender, "", format, v...)
 }

dataprovider/mysql.go

@@ -35,6 +35,10 @@ func initializeMySQLProvider() error {
 	return err
 }
 
+func (p MySQLProvider) checkAvailability() error {
+	return sqlCommonCheckAvailability(p.dbHandle)
+}
+
 func (p MySQLProvider) validateUserAndPass(username string, password string) (User, error) {
 	return sqlCommonValidateUserAndPass(username, password, p.dbHandle)
 }

dataprovider/pgsql.go

@@ -33,6 +33,10 @@ func initializePGSQLProvider() error {
 	return err
 }
 
+func (p PGSQLProvider) checkAvailability() error {
+	return sqlCommonCheckAvailability(p.dbHandle)
+}
+
 func (p PGSQLProvider) validateUserAndPass(username string, password string) (User, error) {
 	return sqlCommonValidateUserAndPass(username, password, p.dbHandle)
 }

dataprovider/sqlcommon.go

@@ -50,6 +50,10 @@ func sqlCommonValidateUserAndPubKey(username string, pubKey string, dbHandle *sq
 	return checkUserAndPubKey(user, pubKey)
 }
 
+func sqlCommonCheckAvailability(dbHandle *sql.DB) error {
+	return dbHandle.Ping()
+}
+
 func sqlCommonGetUserByID(ID int64, dbHandle *sql.DB) (User, error) {
 	var user User
 	q := getUserByIDQuery()

dataprovider/sqlite.go

@@ -50,6 +50,10 @@ func initializeSQLiteProvider(basePath string) error {
 	return err
 }
 
+func (p SQLiteProvider) checkAvailability() error {
+	return sqlCommonCheckAvailability(p.dbHandle)
+}
+
 func (p SQLiteProvider) validateUserAndPass(username string, password string) (User, error) {
 	return sqlCommonValidateUserAndPass(username, password, p.dbHandle)
 }

go.mod

@@ -12,6 +12,10 @@ require (
 	github.com/mattn/go-sqlite3 v1.11.0
 	github.com/pelletier/go-toml v1.4.0 // indirect
 	github.com/pkg/sftp v1.10.2-0.20190913011139-8fc59612f2b0
+	github.com/prometheus/client_golang v1.1.0
+	github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4 // indirect
+	github.com/prometheus/common v0.7.0 // indirect
+	github.com/prometheus/procfs v0.0.4 // indirect
 	github.com/rs/xid v1.2.1
 	github.com/rs/zerolog v1.15.0
 	github.com/spf13/afero v1.2.2 // indirect
@@ -19,9 +23,9 @@ require (
 	github.com/spf13/jwalterweatherman v1.1.0 // indirect
 	github.com/spf13/viper v1.4.0
 	go.etcd.io/bbolt v1.3.3
-	golang.org/x/crypto v0.0.0-20190829043050-9756ffdc2472
+	golang.org/x/crypto v0.0.0-20190911031432-227b76d455e7
 	golang.org/x/net v0.0.0-20190827160401-ba9fcec4b297 // indirect
-	golang.org/x/sys v0.0.0-20190830142957-1e83adbbebd0 // indirect
+	golang.org/x/sys v0.0.0-20190913121621-c3b328c6e5a7 // indirect
 	google.golang.org/appengine v1.6.2 // indirect
 	gopkg.in/natefinch/lumberjack.v2 v2.0.0
 )

go.sum

@@ -1,13 +1,18 @@
 cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
+github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/OneOfOne/xxhash v1.2.2/go.mod h1:HSdplMjZKSmBqAxg5vPj2TmRDmfkzw+cTzAElWljhcU=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
+github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
+github.com/alecthomas/units v0.0.0-20190717042225-c3de453c63f4/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
 github.com/alexedwards/argon2id v0.0.0-20190612080829-01a59b2b8802 h1:RwMM1q/QSKYIGbHfOkf843hE8sSUJtf1dMwFPtEDmm0=
 github.com/alexedwards/argon2id v0.0.0-20190612080829-01a59b2b8802/go.mod h1:4dsm7ufQm1Gwl8S2ss57u+2J7KlxIL2QUmFGlGtWogY=
 github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
 github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
 github.com/beorn7/perks v1.0.0/go.mod h1:KWe93zE9D1o94FZ5RNwFwVgaQK1VOXiVxmqh+CedLV8=
+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 v1.1.0/go.mod h1:XrSqR1VqqWfGrhpAt58auRo0WTKS1nRRg3ghfAqPWnc=
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
 github.com/coreos/bbolt v1.3.2/go.mod h1:iRUV2dpdMOn7Bo10OQBFzIJO9kkE559Wcmn+qkEiiKk=
@@ -18,6 +23,7 @@ github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7
 github.com/coreos/pkg v0.0.0-20180928190104-399ea9e2e55f/go.mod h1:E3G3o1h8I7cfcXa63jLwjI0eiQQMgzzUDFVpN/nH/eA=
 github.com/cpuguy83/go-md2man v1.0.10/go.mod h1:SmD6nW6nTyfqj6ABTjUi3V3JVMnlJmwcJI5acqYI6dE=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+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/dgrijalva/jwt-go v3.2.0+incompatible/go.mod h1:E3ru+11k8xSBh+hMPgOLZmtrrCbhqsmaPHjLKYnJCaQ=
 github.com/dgryski/go-sip13 v0.0.0-20181026042036-e10d5fee7954/go.mod h1:vAd38F8PWV+bWy6jNmig1y/TA+kYO4g3RSRF0IAv0no=
@@ -29,6 +35,7 @@ github.com/go-chi/chi v4.0.2+incompatible/go.mod h1:eB3wogJHnLi3x/kFX2A+IbTBlXxm
 github.com/go-chi/render v1.0.1 h1:4/5tis2cKaNdnv9zFLfXzcquC9HbeZgCnxGnKrltBS8=
 github.com/go-chi/render v1.0.1/go.mod h1:pq4Rr7HbnsdaeHagklXub+p6Wd16Af5l9koip1OvJns=
 github.com/go-kit/kit v0.8.0/go.mod h1:xBxKIO96dXMWWy0MnWVtmwkA9/13aqxPnvrjFYMA2as=
+github.com/go-kit/kit v0.9.0/go.mod h1:xBxKIO96dXMWWy0MnWVtmwkA9/13aqxPnvrjFYMA2as=
 github.com/go-logfmt/logfmt v0.3.0/go.mod h1:Qt1PoO58o5twSAckw1HlFXLmHsOX5/0LbT9GBnD5lWE=
 github.com/go-logfmt/logfmt v0.4.0/go.mod h1:3RMwSq7FuexP4Kalkev3ejPJsZTpXXBr9+V4qmtdjCk=
 github.com/go-sql-driver/mysql v1.4.1 h1:g24URVg0OFbNUTx9qqY1IRZ9D9z3iPyi5zKhQZpNwpA=
@@ -41,16 +48,24 @@ github.com/golang/groupcache v0.0.0-20190129154638-5b532d6fd5ef/go.mod h1:cIg4er
 github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/golang/protobuf v1.3.2 h1:6nsPYzhq5kReh6QImI3k5qWzO4PEbvbIW2cwSfR/6xs=
+github.com/golang/protobuf v1.3.2/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/google/btree v1.0.0/go.mod h1:lNA+9X1NB3Zf8V7Ke586lFgjr2dZNuvo3lPJSGZ5JPQ=
 github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
+github.com/google/go-cmp v0.3.0 h1:crn/baboCvb5fXaQ0IJ1SGTsTVrWpDsCWC8EGETZijY=
+github.com/google/go-cmp v0.3.0/go.mod h1:8QqcDgzrUqlUb/G2PQTWiueGozuR1884gddMywk6iLU=
+github.com/google/gofuzz v1.0.0/go.mod h1:dBl0BpW6vV/+mYPU4Po3pmUjxk6FQPldtuIdl/M65Eg=
 github.com/gorilla/websocket v1.4.0/go.mod h1:E7qHFY5m1UJ88s3WnNqhKjPHQ0heANvMoAMk2YaljkQ=
 github.com/grpc-ecosystem/go-grpc-middleware v1.0.0/go.mod h1:FiyG127CGDf3tlThmgyCl78X/SZQqEOJBCDaAfeWzPs=
 github.com/grpc-ecosystem/go-grpc-prometheus v1.2.0/go.mod h1:8NvIoxWQoOIhqOTXgfV/d3M/q6VIi02HzZEHgUlZvzk=
 github.com/grpc-ecosystem/grpc-gateway v1.9.0/go.mod h1:vNeuVxBJEsws4ogUvrchl83t/GYV9WGTSLVdBhOQFDY=
 github.com/hashicorp/hcl v1.0.0 h1:0Anlzjpi4vEasTeNFn2mLJgTSwt0+6sfsiTG8qcWGx4=
 github.com/hashicorp/hcl v1.0.0/go.mod h1:E5yfLk+7swimpb2L/Alb/PJmXilQ/rhwaUYs4T20WEQ=
+github.com/inconshreveable/mousetrap v1.0.0 h1:Z8tu5sraLXCXIcARxBp/8cbvlwVa7Z1NHg9XEKhtSvM=
 github.com/inconshreveable/mousetrap v1.0.0/go.mod h1:PxqpIevigyE2G7u3NXJIT2ANytuPF1OarO4DADm73n8=
 github.com/jonboulle/clockwork v0.1.0/go.mod h1:Ii8DK3G1RaLaWxj9trq07+26W01tbo22gdxWY5EU2bo=
+github.com/json-iterator/go v1.1.6/go.mod h1:+SdeFBvtyEkXs7REEP0seUULqWtbJapLOCVDaaPEHmU=
+github.com/json-iterator/go v1.1.7/go.mod h1:KdQUCv79m/52Kvf8AW2vK1V8akMuk1QjK/uOdHXbAo4=
 github.com/julienschmidt/httprouter v1.2.0/go.mod h1:SYymIcj16QtmaHHD7aYtjjsJG7VTCxuUUipMqKk8s4w=
 github.com/kisielk/errcheck v1.1.0/go.mod h1:EZBBE59ingxPouuu3KfxchcWSUPOHkagtvWXihfKN4Q=
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
@@ -58,8 +73,10 @@ github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxv
 github.com/kr/fs v0.1.0 h1:Jskdu9ieNAYnjxsi0LbQp1ulIKZV1LAFgK1tWhpZgl8=
 github.com/kr/fs v0.1.0/go.mod h1:FFnZGqtBN9Gxj7eW1uZ42v5BccTP0vu6NEaFoC2HwRg=
 github.com/kr/logfmt v0.0.0-20140226030751-b84e30acd515/go.mod h1:+0opPa2QZZtGFBFZlji/RkVcI2GknAs/DXo4wKdlNEc=
+github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
+github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/lib/pq v1.2.0 h1:LXpIM/LZ5xGFhOpXAQUIMM1HdyqzVYM13zNdjCEEcA0=
 github.com/lib/pq v1.2.0/go.mod h1:5WUZQaWbwv1U+lTReE5YruASi9Al49XbQIvNi/34Woo=
@@ -68,10 +85,15 @@ github.com/magiconair/properties v1.8.1 h1:ZC2Vc7/ZFkGmsVC9KvOjumD+G5lXy2RtTKyzR
 github.com/magiconair/properties v1.8.1/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
 github.com/mattn/go-sqlite3 v1.11.0 h1:LDdKkqtYlom37fkvqs8rMPFKAMe8+SgjbwZ6ex1/A/Q=
 github.com/mattn/go-sqlite3 v1.11.0/go.mod h1:FPy6KqzDD04eiIsT53CuJW3U88zkxoIYsOqkbpncsNc=
+github.com/matttproud/golang_protobuf_extensions v1.0.1 h1:4hp9jkHxhMHkqkrB3Ix0jegS5sx/RkqARlsWZ6pIwiU=
 github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/mitchellh/mapstructure v1.1.2 h1:fmNYVwqnSfB9mZU6OS2O6GsXM+wcskZDuKQzvN1EDeE=
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
+github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
+github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
+github.com/modern-go/reflect2 v0.0.0-20180701023420-4b7aa43c6742/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
+github.com/modern-go/reflect2 v1.0.1/go.mod h1:bx2lNnkwVCuqBIxFjflWJWanXIb3RllmbCylyMrvgv0=
 github.com/mwitkow/go-conntrack v0.0.0-20161129095857-cc309e4a2223/go.mod h1:qRWi+5nqEBWmkhHvq77mSJWrCKwh8bxhgT7d/eI7P4U=
 github.com/oklog/ulid v1.3.1/go.mod h1:CirwcVhetQ6Lv90oh/F+FBtV6XMibvdAFo93nm5qn4U=
 github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic=
@@ -80,19 +102,34 @@ github.com/pelletier/go-toml v1.4.0/go.mod h1:PN7xzY2wHTK0K9p34ErDQMlFxa51Fk0OUr
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
-github.com/pkg/sftp v1.10.1 h1:VasscCm72135zRysgrJDKsntdmPN+OuU3+nnHYA9wyc=
-github.com/pkg/sftp v1.10.1/go.mod h1:lYOWFsE0bwd1+KfKJaKeuokY15vzFx25BLbzYYoAxZI=
 github.com/pkg/sftp v1.10.2-0.20190913011139-8fc59612f2b0 h1:uSPJdIuCJRCOQWSER5+E2xC2KwmgKR4XFGiOSlJdsqA=
 github.com/pkg/sftp v1.10.2-0.20190913011139-8fc59612f2b0/go.mod h1:lYOWFsE0bwd1+KfKJaKeuokY15vzFx25BLbzYYoAxZI=
+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 v0.9.1/go.mod h1:7SWBe2y4D6OKWSNQJUaRYU/AaXPKyh/dDVn+NZz0KFw=
 github.com/prometheus/client_golang v0.9.3/go.mod h1:/TN21ttK/J9q6uSwhBd54HahCDft0ttaMvbicHlPoso=
+github.com/prometheus/client_golang v1.0.0/go.mod h1:db9x61etRT2tGnBNRi70OPL5FsnadC4Ky3P0J6CfImo=
+github.com/prometheus/client_golang v1.1.0 h1:BQ53HtBmfOitExawJ6LokA4x8ov/z0SYYb0+HxJfRI8=
+github.com/prometheus/client_golang v1.1.0/go.mod h1:I1FGZT9+L76gKKOs5djB6ezCbFQP1xR9D75/vuwEF3g=
 github.com/prometheus/client_model v0.0.0-20180712105110-5c3871d89910/go.mod h1:MbSGuTsp3dbXC40dX6PRTWyKYBIrTGTE9sqQNg2J8bo=
+github.com/prometheus/client_model v0.0.0-20190129233127-fd36f4220a90 h1:S/YWwWx/RA8rT8tKFRuGUZhuA90OyIBpPCXkcbwU8DE=
 github.com/prometheus/client_model v0.0.0-20190129233127-fd36f4220a90/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
+github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4 h1:gQz4mCbXsO+nc9n1hCxHcGA3Zx3Eo+UHZoInFGUIXNM=
+github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
 github.com/prometheus/common v0.0.0-20181113130724-41aa239b4cce/go.mod h1:daVV7qP5qjZbuso7PdcryaAu0sAZbrN9i7WWcTMWvro=
 github.com/prometheus/common v0.4.0/go.mod h1:TNfzLD0ON7rHzMJeJkieUDPYmFC7Snx/y86RQel1bk4=
+github.com/prometheus/common v0.4.1/go.mod h1:TNfzLD0ON7rHzMJeJkieUDPYmFC7Snx/y86RQel1bk4=
+github.com/prometheus/common v0.6.0 h1:kRhiuYSXR3+uv2IbVbZhUxK5zVD/2pp3Gd2PpvPkpEo=
+github.com/prometheus/common v0.6.0/go.mod h1:eBmuwkDJBwy6iBfxCBob6t6dR6ENT/y+J+Zk0j9GMYc=
+github.com/prometheus/common v0.7.0 h1:L+1lyG48J1zAQXA3RBX/nG/B3gjlHq0zTt2tlbJLyCY=
+github.com/prometheus/common v0.7.0/go.mod h1:DjGbpBbp5NYNiECxcL/VnbXCCaQpKd3tt26CguLLsqA=
 github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
 github.com/prometheus/procfs v0.0.0-20190507164030-5867b95ac084/go.mod h1:TjEm7ze935MbeOT/UhFTIMYKhuLP4wbCsTZCD3I8kEA=
+github.com/prometheus/procfs v0.0.2/go.mod h1:TjEm7ze935MbeOT/UhFTIMYKhuLP4wbCsTZCD3I8kEA=
+github.com/prometheus/procfs v0.0.3 h1:CTwfnzjQ+8dS6MhHHu4YswVAD99sL2wjPqP+VkURmKE=
+github.com/prometheus/procfs v0.0.3/go.mod h1:4A/X28fw3Fc593LaREMrKMqOKvUAntwMDaekg4FpcdQ=
+github.com/prometheus/procfs v0.0.4 h1:w8DjqFMJDjuVwdZBQoOozr4MVWOnwF7RcL/7uxBjY78=
+github.com/prometheus/procfs v0.0.4/go.mod h1:4A/X28fw3Fc593LaREMrKMqOKvUAntwMDaekg4FpcdQ=
 github.com/prometheus/tsdb v0.7.1/go.mod h1:qhTCs0VvXwvX/y3TZrWD7rabWM+ijKTux40TwIPHuXU=
 github.com/rogpeppe/fastuuid v0.0.0-20150106093220-6724a57986af/go.mod h1:XWv6SoW27p1b0cqNHllgS5HIMJraePCO15w5zCzIWYg=
 github.com/rs/xid v1.2.1 h1:mhH9Nq+C1fY2l1XIpgxIiUOfNpRBYH1kKcr+qfKgjRc=
@@ -101,6 +138,7 @@ github.com/rs/zerolog v1.15.0 h1:uPRuwkWF4J6fGsJ2R0Gn2jB1EQiav9k3S6CSdygQJXY=
 github.com/rs/zerolog v1.15.0/go.mod h1:xYTKnLHcpfU2225ny5qZjxnj9NvkumZYjJHlAThCjNc=
 github.com/russross/blackfriday v1.5.2/go.mod h1:JO/DiYxRf+HjHt06OyowR9PTA263kcR/rfWxYHBV53g=
 github.com/sirupsen/logrus v1.2.0/go.mod h1:LxeOpSwHxABJmUn/MG1IvRgCAasNZTLOkJPxbbu5VWo=
+github.com/sirupsen/logrus v1.4.2/go.mod h1:tLMulIdttU9McNUspp0xgXVQah82FyeX6MwdIuYE2rE=
 github.com/soheilhy/cmux v0.1.4/go.mod h1:IM3LyeVVIOuxMH7sFAkER9+bJ4dT7Ms6E4xg4kGIyLM=
 github.com/spaolacci/murmur3 v0.0.0-20180118202830-f09979ecbc72/go.mod h1:JwIasOWyU6f++ZhiEuf87xNszmSA2myDM2Kzu9HwQUA=
 github.com/spf13/afero v1.1.2/go.mod h1:j4pytiNVoe2o6bmDsKpLACNPDBIoEAkihy7loJ1B0CQ=
@@ -121,6 +159,8 @@ github.com/spf13/viper v1.4.0/go.mod h1:PTJ7Z/lr49W6bUbkmS1V3by4uWynFiR9p7+dSq/y
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
+github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
+github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/tmc/grpc-websocket-proxy v0.0.0-20190109142713-0ad062ec5ee5/go.mod h1:ncp9v5uamzpCO7NfCPTXjqaC+bZgJeR0sMTm6dMHP7U=
 github.com/ugorji/go v1.1.4/go.mod h1:uQMGLiO92mf5W77hV/PUCpI3pbzQx3CRekS0kk+RGrc=
@@ -139,8 +179,8 @@ golang.org/x/crypto v0.0.0-20181203042331-505ab145d0a9/go.mod h1:6SG95UA2DQfeDnf
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20190605123033-f99c8df09eb5/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/crypto v0.0.0-20190820162420-60c769a6c586/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
-golang.org/x/crypto v0.0.0-20190829043050-9756ffdc2472 h1:Gv7RPwsi3eZ2Fgewe3CBsuOebPwO27PoXzRpJPsvSSM=
-golang.org/x/crypto v0.0.0-20190829043050-9756ffdc2472/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
+golang.org/x/crypto v0.0.0-20190911031432-227b76d455e7 h1:0hQKqeLdqlt5iIwVOBErRisrHJAN57yOiPRQItI20fU=
+golang.org/x/crypto v0.0.0-20190911031432-227b76d455e7/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/lint v0.0.0-20181026193005-c67002cb31c3/go.mod h1:UVdnD1Gm6xHRNCYTkRU2/jEulfH38KcIWyp/GAMgvoE=
 golang.org/x/lint v0.0.0-20190313153728-d0100b6bd8b3/go.mod h1:6SW0HCj/g11FgYtHlgUYUwCkIfeOF89ocIRzGO/8vkc=
 golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
@@ -150,6 +190,8 @@ golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190522155817-f3200d17e092/go.mod h1:HSz+uSET+XFnRR8LxR5pz3Of3rY3CfYBVs4xY44aLks=
 golang.org/x/net v0.0.0-20190603091049-60506f45cf65/go.mod h1:HSz+uSET+XFnRR8LxR5pz3Of3rY3CfYBVs4xY44aLks=
+golang.org/x/net v0.0.0-20190613194153-d28f0bde5980/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20190827160401-ba9fcec4b297 h1:k7pJ2yAPLPgbskkFdhRCsA77k2fySZ1zf2zCjvQCiIM=
 golang.org/x/net v0.0.0-20190827160401-ba9fcec4b297/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -163,9 +205,11 @@ golang.org/x/sys v0.0.0-20181116152217-5ac8a444bdc5/go.mod h1:STP8DvDyc/dI5b8T5h
 golang.org/x/sys v0.0.0-20181205085412-a5c9d58dba9a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20190422165155-953cdadca894/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190606165138-5da285871e9c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20190830142957-1e83adbbebd0 h1:7z820YPX9pxWR59qM7BE5+fglp4D/mKqAwCvGt11b+8=
-golang.org/x/sys v0.0.0-20190830142957-1e83adbbebd0/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20190801041406-cbf593c0f2f3/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20190913121621-c3b328c6e5a7 h1:wYqz/tQaWUgGKyx+B/rssSE6wkIKdY5Ee6ryOmzarIg=
+golang.org/x/sys v0.0.0-20190913121621-c3b328c6e5a7/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
@@ -177,12 +221,14 @@ golang.org/x/tools v0.0.0-20190311212946-11955173bddd/go.mod h1:LCzVGOaR6xXOjkQ3
 golang.org/x/tools v0.0.0-20190425163242-31fd60d6bfdc/go.mod h1:RgjU9mgBXZiqYHBnxXauZ1Gv1EHHAz9KjViQ78xBX0Q=
 golang.org/x/tools v0.0.0-20190606124116-d0a3d012864b/go.mod h1:/rFqwRUd4F7ZHNgwSSTFct+R/Kf4OFW1sUzUTQQTgfc=
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
+google.golang.org/appengine v1.6.2 h1:j8RI1yW0SkI+paT6uGwMlrMI/6zwYA6/CFil8rxOzGI=
 google.golang.org/appengine v1.6.2/go.mod h1:i06prIuMbXzDqacNJfV5OdTW448YApPu5ww/cMBSeb0=
 google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
 google.golang.org/grpc v1.19.0/go.mod h1:mqu4LbDTu4XGKhr4mRzUsmM4RtVoemTSY81AxZiDr8c=
 google.golang.org/grpc v1.21.0/go.mod h1:oYelfM1adQP15Ek0mdvEgi9Df8B9CZIaU1084ijfRaM=
 gopkg.in/alecthomas/kingpin.v2 v2.2.6/go.mod h1:FMv+mEhP44yOT+4EoQTLFTRgOQ1FBLkstjWtayDeSgw=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 h1:qIbj1fsPNlZgppZ+VLlY7N33q108Sa+fhmuc+sWQYwY=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/natefinch/lumberjack.v2 v2.0.0 h1:1Lc07Kr7qY4U2YPouBjpCLxpiyxIVoxqXgkXLknAOE8=
 gopkg.in/natefinch/lumberjack.v2 v2.0.0/go.mod h1:l0ndWWf7gzL7RNwBG7wST/UCcT4T24xpD6X8LsfU/+k=

logger/request_logger.go

@@ -5,6 +5,7 @@ import (
 	"net/http"
 	"time"
 
+	"github.com/drakkan/sftpgo/metrics"
 	"github.com/go-chi/chi/middleware"
 	"github.com/rs/zerolog"
 )
@@ -54,6 +55,7 @@ func (l *StructuredLogger) NewLogEntry(r *http.Request) middleware.LogEntry {
 
 // Write logs a new entry at the end of the HTTP request
 func (l *StructuredLoggerEntry) Write(status, bytes int, elapsed time.Duration) {
+	metrics.HTTPRequestServed(status)
 	l.Logger.Info().Fields(l.fields).Int(
 		"resp_status", status).Int(
 		"resp_size", bytes).Int64(

metrics/metrics.go

@@ -0,0 +1,212 @@
+package metrics
+
+import (
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
+)
+
+var (
+	// dataproviderAvailability is the metric that reports the availability for the configured data provider
+	dataproviderAvailability = promauto.NewGauge(prometheus.GaugeOpts{
+		Name: "sftpgo_dataprovider_availability",
+		Help: "Availability for the configured data provider, 1 means OK, 0 KO",
+	})
+
+	// activeConnections is the metric that reports the total number of active connections
+	activeConnections = promauto.NewGauge(prometheus.GaugeOpts{
+		Name: "sftpgo_active_connections",
+		Help: "Total number of logged in users",
+	})
+
+	// totalUploads is the metric that reports the total number of uploads
+	totalUploads = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_uploads_total",
+		Help: "The total number of uploads",
+	})
+
+	// totalDownloads is the metric that reports the total number of downloads
+	totalDownloads = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_downloads_total",
+		Help: "The total number of downloads",
+	})
+
+	// totalUploadErrors is the metric that reports the total number of upload errors
+	totalUploadErrors = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_upload_errors_total",
+		Help: "The total number of upload errors",
+	})
+
+	// totalDownloadErrors is the metric that reports the total number of download errors
+	totalDownloadErrors = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_download_errors_total",
+		Help: "The total number of download errors",
+	})
+
+	// totalUploadSize is the metric that reports the total uploads size as bytes
+	totalUploadSize = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_upload_size",
+		Help: "The total upload size as bytes",
+	})
+
+	// totalDownloadSize is the metric that reports the total downloads size as bytes
+	totalDownloadSize = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_download_size",
+		Help: "The total download size as bytes",
+	})
+
+	// totalLoginAttempts is the metric that reports the total number of login attempts
+	totalLoginAttempts = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_login_attempts_total",
+		Help: "The total number of login attempts",
+	})
+
+	// totalLoginOK is the metric that reports the total number of successfull logins
+	totalLoginOK = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_login_ok_total",
+		Help: "The total number of successfull logins",
+	})
+
+	// totalLoginFailed is the metric that reports the total number of failed logins
+	totalLoginFailed = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_login_ko_total",
+		Help: "The total number of failed logins",
+	})
+
+	// totalPasswordLoginAttempts is the metric that reports the total number of login attempts
+	// using a password
+	totalPasswordLoginAttempts = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_password_login_attempts_total",
+		Help: "The total number of login attempts using a password",
+	})
+
+	// totalPasswordLoginOK is the metric that reports the total number of successfull logins
+	// using a password
+	totalPasswordLoginOK = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_password_login_ok_total",
+		Help: "The total number of successfull logins using a password",
+	})
+
+	// totalPasswordLoginFailed is the metric that reports the total number of failed logins
+	// using a password
+	totalPasswordLoginFailed = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_password_login_ko_total",
+		Help: "The total number of failed logins using a password",
+	})
+
+	// totalKeyLoginAttempts is the metric that reports the total number of login attempts
+	// using a public key
+	totalKeyLoginAttempts = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_public_key_login_attempts_total",
+		Help: "The total number of login attempts using a public key",
+	})
+
+	// totalKeyLoginOK is the metric that reports the total number of successfull logins
+	// using a public key
+	totalKeyLoginOK = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_public_key_login_ok_total",
+		Help: "The total number of successfull logins using a public key",
+	})
+
+	// totalKeyLoginFailed is the metric that reports the total number of failed logins
+	// using a public key
+	totalKeyLoginFailed = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_public_key_login_ko_total",
+		Help: "The total number of failed logins using a public key",
+	})
+
+	totalHTTPRequests = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_http_req_total",
+		Help: "The total number of HTTP requests served",
+	})
+
+	totalHTTPOK = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_http_req_ok_total",
+		Help: "The total number of HTTP requests served with 2xx status code",
+	})
+
+	totalHTTPClientErrors = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_http_client_errors_total",
+		Help: "The total number of HTTP requests served with 4xx status code",
+	})
+
+	totalHTTPServerErrors = promauto.NewCounter(prometheus.CounterOpts{
+		Name: "sftpgo_http_server_errors_total",
+		Help: "The total number of HTTP requests served with 5xx status code",
+	})
+)
+
+// TransferCompleted update metrics after an upload or a download
+func TransferCompleted(bytesSent, bytesReceived int64, transferKind int, err error) {
+	if transferKind == 0 {
+		// upload
+		if err == nil {
+			totalUploads.Inc()
+			totalUploadSize.Add(float64(bytesReceived))
+		} else {
+			totalUploadErrors.Inc()
+		}
+	} else {
+		// download
+		if err == nil {
+			totalDownloads.Inc()
+			totalDownloadSize.Add(float64(bytesSent))
+		} else {
+			totalDownloadErrors.Inc()
+		}
+	}
+}
+
+// UpdateDataProviderAvailability updates the metric for the data provider availability
+func UpdateDataProviderAvailability(err error) {
+	if err == nil {
+		dataproviderAvailability.Set(1)
+	} else {
+		dataproviderAvailability.Set(0)
+	}
+}
+
+// AddLoginAttempt increments the metrics for login attempts
+func AddLoginAttempt(withKey bool) {
+	totalLoginAttempts.Inc()
+	if withKey {
+		totalKeyLoginAttempts.Inc()
+	} else {
+		totalPasswordLoginAttempts.Inc()
+	}
+}
+
+// AddLoginResult increments the metrics for login results
+func AddLoginResult(withKey bool, err error) {
+	if err == nil {
+		totalLoginOK.Inc()
+		if withKey {
+			totalKeyLoginOK.Inc()
+		} else {
+			totalPasswordLoginOK.Inc()
+		}
+	} else {
+		totalLoginFailed.Inc()
+		if withKey {
+			totalKeyLoginFailed.Inc()
+		} else {
+			totalPasswordLoginFailed.Inc()
+		}
+	}
+}
+
+// HTTPRequestServed increments the metrics for HTTP requests
+func HTTPRequestServed(status int) {
+	totalHTTPRequests.Inc()
+	if status >= 200 && status < 300 {
+		totalHTTPOK.Inc()
+	} else if status >= 400 && status < 500 {
+		totalHTTPClientErrors.Inc()
+	} else if status >= 500 {
+		totalHTTPServerErrors.Inc()
+	}
+}
+
+// UpdateActiveConnectionsSize sets the metric for active connections
+func UpdateActiveConnectionsSize(size int) {
+	activeConnections.Set(float64(size))
+}

sftpd/server.go

@@ -21,6 +21,7 @@ import (
 
 	"github.com/drakkan/sftpgo/dataprovider"
 	"github.com/drakkan/sftpgo/logger"
+	"github.com/drakkan/sftpgo/metrics"
 	"github.com/drakkan/sftpgo/utils"
 	"github.com/pkg/sftp"
 	"golang.org/x/crypto/ssh"
@@ -376,21 +377,27 @@ func (c Configuration) validatePublicKeyCredentials(conn ssh.ConnMetadata, pubKe
 	var err error
 	var user dataprovider.User
 	var keyID string
+	var sshPerm *ssh.Permissions
 
+	metrics.AddLoginAttempt(true)
 	if user, keyID, err = dataprovider.CheckUserAndPubKey(dataProvider, conn.User(), pubKey); err == nil {
-		return loginUser(user, "public_key:"+keyID)
+		sshPerm, err = loginUser(user, "public_key:"+keyID)
 	}
-	return nil, err
+	metrics.AddLoginResult(true, err)
+	return sshPerm, err
 }
 
 func (c Configuration) validatePasswordCredentials(conn ssh.ConnMetadata, pass []byte) (*ssh.Permissions, error) {
 	var err error
 	var user dataprovider.User
+	var sshPerm *ssh.Permissions
 
+	metrics.AddLoginAttempt(false)
 	if user, err = dataprovider.CheckUserAndPass(dataProvider, conn.User(), string(pass)); err == nil {
-		return loginUser(user, "password")
+		sshPerm, err = loginUser(user, "password")
 	}
-	return nil, err
+	metrics.AddLoginResult(false, err)
+	return sshPerm, err
 }
 
 // Generates a private key that will be used by the SFTP server.

sftpd/sftpd.go

@@ -15,6 +15,7 @@ import (
 
 	"github.com/drakkan/sftpgo/dataprovider"
 	"github.com/drakkan/sftpgo/logger"
+	"github.com/drakkan/sftpgo/metrics"
 	"github.com/drakkan/sftpgo/utils"
 )
 
@@ -265,6 +266,7 @@ func addConnection(id string, c Connection) {
 	mutex.Lock()
 	defer mutex.Unlock()
 	openConnections[id] = c
+	metrics.UpdateActiveConnectionsSize(len(openConnections))
 	c.Log(logger.LevelDebug, logSender, "connection added, num open connections: %v", len(openConnections))
 }
 
@@ -273,6 +275,7 @@ func removeConnection(id string) {
 	defer mutex.Unlock()
 	c := openConnections[id]
 	delete(openConnections, id)
+	metrics.UpdateActiveConnectionsSize(len(openConnections))
 	c.Log(logger.LevelDebug, logSender, "connection removed, num open connections: %v", len(openConnections))
 }
 

sftpd/transfer.go

@@ -6,6 +6,7 @@ import (
 
 	"github.com/drakkan/sftpgo/dataprovider"
 	"github.com/drakkan/sftpgo/logger"
+	"github.com/drakkan/sftpgo/metrics"
 )
 
 const (
@@ -105,6 +106,7 @@ func (t *Transfer) Close() error {
 			executeAction(operationUpload, t.user.Username, t.path, "")
 		}
 	}
+	metrics.TransferCompleted(t.bytesSent, t.bytesReceived, t.transferType, t.transferError)
 	removeTransfer(t)
 	if t.transferType == transferUpload && (numFiles != 0 || t.bytesReceived > 0) {
 		dataprovider.UpdateUserQuota(dataProvider, t.user, numFiles, t.bytesReceived, false)