add profiler support

profiling is now available via the HTTP base URL /debug/pprof/

examples, use this URL to start and download a 30 seconds CPU profile:

/debug/pprof/profile?seconds=30

use this URL to profile used memory:

/debug/pprof/heap?gc=1

use this URL to profile allocated memory:

/debug/pprof/allocs?gc=1

Full docs here:

https://golang.org/pkg/net/http/pprof/

cmd/portable.go

@@ -91,6 +91,7 @@ Please take a look at the usage below to customize the serving parameters`,
 				LogMaxAge:     defaultLogMaxAge,
 				LogCompress:   defaultLogCompress,
 				LogVerbose:    defaultLogVerbose,
+				Profiler:      defaultProfiler,
 				Shutdown:      make(chan bool),
 				PortableMode:  1,
 				PortableUser: dataprovider.User{

cmd/root.go

@@ -30,6 +30,8 @@ const (
 	logCompressKey      = "log_compress"
 	logVerboseFlag      = "log-verbose"
 	logVerboseKey       = "log_verbose"
+	profilerFlag        = "profiler"
+	profilerKey         = "profiler"
 	defaultConfigDir    = "."
 	defaultConfigName   = config.DefaultConfigName
 	defaultLogFile      = "sftpgo.log"
@@ -38,6 +40,7 @@ const (
 	defaultLogMaxAge    = 28
 	defaultLogCompress  = false
 	defaultLogVerbose   = true
+	defaultProfiler     = false
 )
 
 var (
@@ -49,6 +52,7 @@ var (
 	logMaxAge     int
 	logCompress   bool
 	logVerbose    bool
+	profiler      bool
 
 	rootCmd = &cobra.Command{
 		Use:   "sftpgo",
@@ -135,6 +139,13 @@ func addServeFlags(cmd *cobra.Command) {
 	cmd.Flags().BoolVarP(&logVerbose, logVerboseFlag, "v", viper.GetBool(logVerboseKey), "Enable verbose logs. "+
 		"This flag can be set using SFTPGO_LOG_VERBOSE env var too.")
 	viper.BindPFlag(logVerboseKey, cmd.Flags().Lookup(logVerboseFlag))
+
+	viper.SetDefault(profilerKey, defaultProfiler)
+	viper.BindEnv(profilerKey, "SFTPGO_PROFILER")
+	cmd.Flags().BoolVarP(&profiler, profilerFlag, "p", viper.GetBool(profilerKey), "Enable the built-in profiler. "+
+		"The profiler will be accessible via HTTP/HTTPS using the base URL \"/debug/pprof/\". "+
+		"This flag can be set using SFTPGO_PROFILER env var too.")
+	viper.BindPFlag(profilerKey, cmd.Flags().Lookup(profilerFlag))
 }
 
 func getCustomServeFlags() []string {
@@ -170,5 +181,8 @@ func getCustomServeFlags() []string {
 	if logCompress != defaultLogCompress {
 		result = append(result, "--"+logCompressFlag+"=true")
 	}
+	if profiler != defaultProfiler {
+		result = append(result, "--"+profilerFlag+"=true")
+	}
 	return result
 }

cmd/serve.go

@@ -25,6 +25,7 @@ Please take a look at the usage below to customize the startup options`,
 				LogMaxAge:     logMaxAge,
 				LogCompress:   logCompress,
 				LogVerbose:    logVerbose,
+				Profiler:      profiler,
 				Shutdown:      make(chan bool),
 			}
 			if err := service.Start(); err == nil {

cmd/start_windows.go

@@ -27,6 +27,7 @@ var (
 				LogMaxAge:     logMaxAge,
 				LogCompress:   logCompress,
 				LogVerbose:    logVerbose,
+				Profiler:      profiler,
 				Shutdown:      make(chan bool),
 			}
 			winService := service.WindowsService{

httpd/httpd.go

@@ -30,6 +30,7 @@ const (
 	dumpDataPath          = "/api/v1/dumpdata"
 	loadDataPath          = "/api/v1/loaddata"
 	metricsPath           = "/metrics"
+	pprofBasePath         = "/debug"
 	webBasePath           = "/web"
 	webUsersPath          = "/web/users"
 	webUserPath           = "/web/user"
@@ -85,7 +86,7 @@ func SetDataProvider(provider dataprovider.Provider) {
 }
 
 // Initialize the HTTP server
-func (c Conf) Initialize(configDir string) error {
+func (c Conf) Initialize(configDir string, profiler bool) error {
 	var err error
 	logger.Debug(logSender, "", "initializing HTTP server with config %+v", c)
 	backupsPath = getConfigPath(c.BackupsPath, configDir)
@@ -103,7 +104,7 @@ func (c Conf) Initialize(configDir string) error {
 	certificateFile := getConfigPath(c.CertificateFile, configDir)
 	certificateKeyFile := getConfigPath(c.CertificateKeyFile, configDir)
 	loadTemplates(templatesPath)
-	initializeRouter(staticFilesPath)
+	initializeRouter(staticFilesPath, profiler)
 	httpServer := &http.Server{
 		Addr:           fmt.Sprintf("%s:%d", c.BindAddress, c.BindPort),
 		Handler:        router,

httpd/httpd_test.go

@@ -49,6 +49,7 @@ const (
 	dumpDataPath          = "/api/v1/dumpdata"
 	loadDataPath          = "/api/v1/loaddata"
 	metricsPath           = "/metrics"
+	pprofPath             = "/debug/pprof/"
 	webBasePath           = "/web"
 	webUsersPath          = "/web/users"
 	webUserPath           = "/web/user"
@@ -117,7 +118,7 @@ func TestMain(m *testing.M) {
 	httpd.SetDataProvider(dataProvider)
 
 	go func() {
-		if err := httpdConf.Initialize(configDir); err != nil {
+		if err := httpdConf.Initialize(configDir, true); err != nil {
 			logger.Error(logSender, "", "could not start HTTP server: %v", err)
 		}
 	}()
@@ -133,7 +134,7 @@ func TestMain(m *testing.M) {
 	httpdConf.CertificateKeyFile = keyPath
 
 	go func() {
-		if err := httpdConf.Initialize(configDir); err != nil {
+		if err := httpdConf.Initialize(configDir, true); err != nil {
 			logger.Error(logSender, "", "could not start HTTPS server: %v", err)
 		}
 	}()
@@ -157,7 +158,7 @@ func TestInitialization(t *testing.T) {
 	httpdConf := config.GetHTTPDConfig()
 	httpdConf.BackupsPath = "test_backups"
 	httpdConf.AuthUserFile = "invalid file"
-	err := httpdConf.Initialize(configDir)
+	err := httpdConf.Initialize(configDir, true)
 	if err == nil {
 		t.Error("Inizialize must fail")
 	}
@@ -165,14 +166,14 @@ func TestInitialization(t *testing.T) {
 	httpdConf.AuthUserFile = ""
 	httpdConf.CertificateFile = "invalid file"
 	httpdConf.CertificateKeyFile = "invalid file"
-	err = httpdConf.Initialize(configDir)
+	err = httpdConf.Initialize(configDir, true)
 	if err == nil {
 		t.Error("Inizialize must fail")
 	}
 	httpdConf.CertificateFile = ""
 	httpdConf.CertificateKeyFile = ""
 	httpdConf.TemplatesPath = "."
-	err = httpdConf.Initialize(configDir)
+	err = httpdConf.Initialize(configDir, true)
 	if err == nil {
 		t.Error("Inizialize must fail")
 	}
@@ -1681,6 +1682,12 @@ func TestMetricsMock(t *testing.T) {
 	checkResponseCode(t, http.StatusOK, rr.Code)
 }
 
+func TestPProfEndPointMock(t *testing.T) {
+	req, _ := http.NewRequest(http.MethodGet, pprofPath, nil)
+	rr := executeRequest(req)
+	checkResponseCode(t, http.StatusOK, rr.Code)
+}
+
 func TestGetWebRootMock(t *testing.T) {
 	req, _ := http.NewRequest(http.MethodGet, "/", nil)
 	rr := executeRequest(req)

httpd/router.go

@@ -18,13 +18,19 @@ func GetHTTPRouter() http.Handler {
 	return router
 }
 
-func initializeRouter(staticFilesPath string) {
+func initializeRouter(staticFilesPath string, profiler bool) {
 	router = chi.NewRouter()
 	router.Use(middleware.RequestID)
 	router.Use(middleware.RealIP)
 	router.Use(logger.NewStructuredLogger(logger.GetLogger()))
 	router.Use(middleware.Recoverer)
 
+	if profiler {
+		logger.InfoToConsole("enabling the built-in profiler")
+		logger.Info(logSender, "", "enabling the built-in profiler")
+		router.Mount(pprofBasePath, middleware.Profiler())
+	}
+
 	router.NotFound(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		sendAPIResponse(w, r, nil, "Not Found", http.StatusNotFound)
 	}))

service/service.go

@@ -41,6 +41,7 @@ type Service struct {
 	LogVerbose    bool
 	PortableMode  int
 	PortableUser  dataprovider.User
+	Profiler      bool
 	Shutdown      chan bool
 }
 
@@ -62,8 +63,8 @@ func (s *Service) Start() error {
 	}
 	version := utils.GetAppVersion()
 	logger.Info(logSender, "", "starting SFTPGo %v, config dir: %v, config file: %v, log max size: %v log max backups: %v "+
-		"log max age: %v log verbose: %v, log compress: %v", version.GetVersionAsString(), s.ConfigDir, s.ConfigFile, s.LogMaxSize,
-		s.LogMaxBackups, s.LogMaxAge, s.LogVerbose, s.LogCompress)
+		"log max age: %v log verbose: %v, log compress: %v, profile: %v", version.GetVersionAsString(), s.ConfigDir, s.ConfigFile,
+		s.LogMaxSize, s.LogMaxBackups, s.LogMaxAge, s.LogVerbose, s.LogCompress, s.Profiler)
 	// in portable mode we don't read configuration from file
 	if s.PortableMode != 1 {
 		config.LoadConfig(s.ConfigDir, s.ConfigFile)
@@ -105,7 +106,7 @@ func (s *Service) Start() error {
 		httpd.SetDataProvider(dataProvider)
 
 		go func() {
-			if err := httpdConf.Initialize(s.ConfigDir); err != nil {
+			if err := httpdConf.Initialize(s.ConfigDir, s.Profiler); err != nil {
 				logger.Error(logSender, "", "could not start HTTP server: %v", err)
 				logger.ErrorToConsole("could not start HTTP server: %v", err)
 			}

sftpd/sftpd_test.go

@@ -197,7 +197,7 @@ func TestMain(m *testing.M) {
 	}()
 
 	go func() {
-		if err := httpdConf.Initialize(configDir); err != nil {
+		if err := httpdConf.Initialize(configDir, false); err != nil {
 			logger.Error(logSender, "", "could not start HTTP server: %v", err)
 		}
 	}()