Add better process lifecycle management

Makefile

@@ -33,6 +33,10 @@ testall: check_go_env test
 	@(cd ./ui && npm test -- --watchAll=false)
 .PHONY: testall
 
+lint:
+	golangci-lint run -v
+.PHONY: lint
+
 update-snapshots: check_go_env
 	UPDATE_SNAPSHOTS=true ginkgo ./server/subsonic/...
 .PHONY: update-snapshots
@@ -87,11 +91,7 @@ buildall: check_env
 	go build -ldflags="-X github.com/deluan/navidrome/consts.gitSha=$(GIT_SHA) -X github.com/deluan/navidrome/consts.gitTag=$(GIT_TAG)-SNAPSHOT" -tags=embed
 .PHONY: buildall
 
-pre-push:
-	golangci-lint run -v
-
-	@echo
-	make test
+pre-push: lint test
 .PHONY: pre-push
 
 release:

cmd/root.go

@@ -3,10 +3,13 @@ package cmd
 import (
 	"fmt"
 	"os"
+	"time"
 
 	"github.com/deluan/navidrome/conf"
 	"github.com/deluan/navidrome/consts"
 	"github.com/deluan/navidrome/db"
+	"github.com/deluan/navidrome/log"
+	"github.com/oklog/run"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 )
@@ -24,7 +27,7 @@ Complete documentation is available at https://www.navidrome.org/docs`,
 			preRun()
 		},
 		Run: func(cmd *cobra.Command, args []string) {
-			startServer()
+			runNavidrome()
 		},
 		Version: consts.Version(),
 	}
@@ -45,20 +48,69 @@ func preRun() {
 	conf.Load()
 }
 
-func startServer() {
+func runNavidrome() {
 	db.EnsureLatestVersion()
 
-	subsonic, err := CreateSubsonicAPIRouter()
-	if err != nil {
-		panic(fmt.Sprintf("Could not create the Subsonic API router. Aborting! err=%v", err))
+	var g run.Group
+	g.Add(startServer())
+	if conf.Server.ScanInterval != 0 {
+		g.Add(startScanner())
+	} else {
+		log.Warn("Scanner is disabled", "interval", conf.Server.ScanInterval)
+	}
+	if err := g.Run(); err != nil {
+		log.Error("Fatal error in Navidrome. Aborting", err)
 	}
-	a := CreateServer(conf.Server.MusicFolder)
-	a.MountRouter(consts.URLPathSubsonicAPI, subsonic)
-	a.MountRouter(consts.URLPathUI, CreateAppRouter())
-	a.Run(fmt.Sprintf("%s:%d", conf.Server.Address, conf.Server.Port))
 }
 
-// TODO: Implemement some struct tags to map flags to viper
+func startServer() (func() error, func(err error)) {
+	return func() error {
+			a := CreateServer(conf.Server.MusicFolder)
+			a.MountRouter(consts.URLPathSubsonicAPI, CreateSubsonicAPIRouter())
+			a.MountRouter(consts.URLPathUI, CreateAppRouter())
+			return a.Run(fmt.Sprintf("%s:%d", conf.Server.Address, conf.Server.Port))
+		}, func(err error) {
+			if err != nil {
+				log.Error("Fatal error executing Scanner", err)
+			} else {
+				log.Info("Shutting down Scanner")
+			}
+		}
+}
+
+func startScanner() (func() error, func(err error)) {
+	interval := conf.Server.ScanInterval
+	log.Info("Starting scanner", "interval", interval.String())
+	scanner := CreateScanner(conf.Server.MusicFolder)
+
+	ticker := time.NewTicker(interval)
+	done := make(chan bool)
+
+	return func() error {
+			time.Sleep(2 * time.Second) // Wait 2 seconds before the first scan
+			for {
+				if err := scanner.RescanAll(false); err != nil {
+					log.Error("Error scanning media folder", "folder", conf.Server.MusicFolder, err)
+				}
+				select {
+				case <-ticker.C:
+					continue
+				case <-done:
+					return nil
+				}
+			}
+		}, func(err error) {
+			ticker.Stop()
+			done <- true
+			if err != nil {
+				log.Error("Fatal error executing Scanner", err)
+			} else {
+				log.Info("Shutting down Scanner")
+			}
+		}
+}
+
+// TODO: Implement some struct tags to map flags to viper
 func init() {
 	cobra.OnInitialize(func() {
 		conf.InitConfig(cfgFile)

cmd/wire_gen.go

@@ -21,8 +21,7 @@ import (
 
 func CreateServer(musicFolder string) *server.Server {
 	dataStore := persistence.New()
-	scannerScanner := scanner.New(dataStore)
-	serverServer := server.New(scannerScanner, dataStore)
+	serverServer := server.New(dataStore)
 	return serverServer
 }
 
@@ -38,7 +37,7 @@ func CreateAppRouter() *app.Router {
 	return router
 }
 
-func CreateSubsonicAPIRouter() (*subsonic.Router, error) {
+func CreateSubsonicAPIRouter() *subsonic.Router {
 	dataStore := persistence.New()
 	artworkCache := core.NewImageCache()
 	artwork := core.NewArtwork(dataStore, artworkCache)
@@ -54,7 +53,7 @@ func CreateSubsonicAPIRouter() (*subsonic.Router, error) {
 	spotifyClient := core.SpotifyNewClient()
 	externalInfo := core.NewExternalInfo(dataStore, client, spotifyClient)
 	router := subsonic.New(artwork, listGenerator, playlists, mediaStreamer, archiver, players, externalInfo, dataStore)
-	return router, nil
+	return router
 }
 
 // wire_injectors.go:

cmd/wire_injectors.go

@@ -39,6 +39,6 @@ func CreateAppRouter() *app.Router {
 	panic(wire.Build(allProviders))
 }
 
-func CreateSubsonicAPIRouter() (*subsonic.Router, error) {
+func CreateSubsonicAPIRouter() *subsonic.Router {
 	panic(wire.Build(allProviders))
 }

go.mod

@@ -26,6 +26,7 @@ require (
 	github.com/mattn/go-sqlite3 v2.0.3+incompatible
 	github.com/microcosm-cc/bluemonday v1.0.4
 	github.com/mitchellh/mapstructure v1.3.2 // indirect
+	github.com/oklog/run v1.1.0
 	github.com/onsi/ginkgo v1.14.2
 	github.com/onsi/gomega v1.10.3
 	github.com/pelletier/go-toml v1.8.0 // indirect

go.sum

@@ -382,6 +382,8 @@ github.com/nxadm/tail v1.4.4 h1:DQuhQpB1tVlglWS2hLQ5OV6B5r8aGxSrPc5Qo6uTN78=
 github.com/nxadm/tail v1.4.4/go.mod h1:kenIhsEOeOJmVchQTgglprH7qJGnHDVpk1VPCcaMI8A=
 github.com/ogier/pflag v0.0.1 h1:RW6JSWSu/RkSatfcLtogGfFgpim5p7ARQ10ECk5O750=
 github.com/ogier/pflag v0.0.1/go.mod h1:zkFki7tvTa0tafRvTBIZTvzYyAu6kQhPZFnshFFPE+g=
+github.com/oklog/run v1.1.0 h1:GEenZ1cK0+q0+wsJew9qUg/DyD8k3JzYsZAi5gYi2mA=
+github.com/oklog/run v1.1.0/go.mod h1:sVPdnTZT1zYwAJeCMu2Th4T21pA3FPOQRfWjQlk7DVU=
 github.com/oklog/ulid v1.3.1/go.mod h1:CirwcVhetQ6Lv90oh/F+FBtV6XMibvdAFo93nm5qn4U=
 github.com/onsi/ginkgo v1.6.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
 github.com/onsi/ginkgo v1.12.0/go.mod h1:oUhWkIvk5aDxtKvDDuw8gItl8pKl42LzjC9KZE0HfGg=

server/server.go

@@ -3,14 +3,12 @@ package server
 import (
 	"net/http"
 	"path"
-	"time"
 
 	"github.com/deluan/navidrome/assets"
 	"github.com/deluan/navidrome/conf"
 	"github.com/deluan/navidrome/consts"
 	"github.com/deluan/navidrome/log"
 	"github.com/deluan/navidrome/model"
-	"github.com/deluan/navidrome/scanner"
 	"github.com/go-chi/chi"
 	"github.com/go-chi/chi/middleware"
 	"github.com/go-chi/cors"
@@ -22,16 +20,14 @@ type Handler interface {
 }
 
 type Server struct {
-	Scanner *scanner.Scanner
-	router  *chi.Mux
-	ds      model.DataStore
+	router *chi.Mux
+	ds     model.DataStore
 }
 
-func New(scanner *scanner.Scanner, ds model.DataStore) *Server {
-	a := &Server{Scanner: scanner, ds: ds}
+func New(ds model.DataStore) *Server {
+	a := &Server{ds: ds}
 	initialSetup(ds)
 	a.initRoutes()
-	a.initScanner()
 	checkFfmpegInstallation()
 	checkExternalCredentials()
 	return a
@@ -47,9 +43,9 @@ func (a *Server) MountRouter(urlPath string, subRouter Handler) {
 	})
 }
 
-func (a *Server) Run(addr string) {
+func (a *Server) Run(addr string) error {
 	log.Info("Navidrome server is accepting requests", "address", addr)
-	log.Error(http.ListenAndServe(addr, a.router))
+	return http.ListenAndServe(addr, a.router)
 }
 
 func (a *Server) initRoutes() {
@@ -72,22 +68,3 @@ func (a *Server) initRoutes() {
 
 	a.router = r
 }
-
-func (a *Server) initScanner() {
-	interval := conf.Server.ScanInterval
-	if interval == 0 {
-		log.Warn("Scanner is disabled", "interval", conf.Server.ScanInterval)
-		return
-	}
-	log.Info("Starting scanner", "interval", interval.String())
-	go func() {
-		time.Sleep(2 * time.Second)
-		for {
-			err := a.Scanner.RescanAll(false)
-			if err != nil {
-				log.Error("Error scanning media folder", "folder", conf.Server.MusicFolder, err)
-			}
-			time.Sleep(interval)
-		}
-	}()
-}