Resolve race condition issues

cmd/zurg/main.go

@@ -1,12 +1,17 @@
 package main
 
 import (
+	"context"
 	"fmt"
 	"log"
 	"net/http"
+	"os"
+	"os/signal"
+	"syscall"
 	"time"
 
 	"github.com/debridmediamanager.com/zurg/internal/config"
+	"github.com/debridmediamanager.com/zurg/internal/mount"
 	"github.com/debridmediamanager.com/zurg/internal/net"
 	"github.com/debridmediamanager.com/zurg/internal/torrent"
 	"github.com/hashicorp/golang-lru/v2/expirable"
@@ -26,9 +31,31 @@ func main() {
 	net.Router(mux, config, t, cache)
 
 	addr := fmt.Sprintf(":%s", config.GetPort())
+	server := &http.Server{Addr: addr, Handler: mux}
+
+	shutdown := make(chan os.Signal, 1)
+	signal.Notify(shutdown, os.Interrupt, syscall.SIGTERM)
+
+	go func() {
 		log.Printf("Starting server on %s\n", addr)
-	err := http.ListenAndServe(addr, mux)
+		if err := server.ListenAndServe(); err != nil && err != http.ErrServerClosed {
-	if err != nil {
 			log.Panicf("Failed to start server: %v", err)
 		}
+	}()
+
+	// Start the mount in a goroutine.
+	go func() {
+		if err := mount.Mount(config.GetMountPath()); err != nil {
+			log.Panicf("Failed to mount: %v", err)
+		}
+	}()
+
+	<-shutdown
+	log.Println("zurg signing off...")
+
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	server.Shutdown(ctx)
+
 }

go.mod

@@ -6,3 +6,11 @@ require (
 	github.com/hashicorp/golang-lru/v2 v2.0.7
 	gopkg.in/yaml.v3 v3.0.1
 )
+
+require (
+	bazil.org/fuse v0.0.0-20230120002735-62a210ff1fd5 // indirect
+	github.com/mdlayher/sdnotify v1.0.0 // indirect
+	go.uber.org/multierr v1.11.0 // indirect
+	go.uber.org/zap v1.26.0 // indirect
+	golang.org/x/sys v0.4.0 // indirect
+)

go.sum

@@ -1,5 +1,15 @@
+bazil.org/fuse v0.0.0-20230120002735-62a210ff1fd5 h1:A0NsYy4lDBZAC6QiYeJ4N+XuHIKBpyhAVRMHRQZKTeQ=
+bazil.org/fuse v0.0.0-20230120002735-62a210ff1fd5/go.mod h1:gG3RZAMXCa/OTes6rr9EwusmR1OH1tDDy+cg9c5YliY=
 github.com/hashicorp/golang-lru/v2 v2.0.7 h1:a+bsQ5rvGLjzHuww6tVxozPZFVghXaHOwFs4luLUK2k=
 github.com/hashicorp/golang-lru/v2 v2.0.7/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
+github.com/mdlayher/sdnotify v1.0.0 h1:Ma9XeLVN/l0qpyx1tNeMSeTjCPH6NtuD6/N9XdTlQ3c=
+github.com/mdlayher/sdnotify v1.0.0/go.mod h1:HQUmpM4XgYkhDLtd+Uad8ZFK1T9D5+pNxnXQjCeJlGE=
+go.uber.org/multierr v1.11.0 h1:blXXJkSxSSfBVBlC76pxqeO+LN3aDfLQo+309xJstO0=
+go.uber.org/multierr v1.11.0/go.mod h1:20+QtiLqy0Nd6FdQB9TLXag12DsQkrbs3htMFfDN80Y=
+go.uber.org/zap v1.26.0 h1:sI7k6L95XOKS281NhVKOFCUNIvv9e0w4BF8N3u+tCRo=
+go.uber.org/zap v1.26.0/go.mod h1:dtElttAiwGvoJ/vj4IwHBS/gXsEu/pZ50mUIRWuG0so=
+golang.org/x/sys v0.4.0 h1:Zr2JFtRQNX3BCZ8YtxRE9hNJYC8J6I1MVbMg6owUp18=
+golang.org/x/sys v0.4.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=

internal/config/load.go

@@ -19,6 +19,7 @@ type ConfigInterface interface {
 	MeetsConditions(directory, torrentID, torrentName string, fileNames []string) bool
 	GetOnLibraryUpdate() string
 	GetNetworkBufferSize() int
+	GetMountPath() string
 }
 
 func LoadZurgConfig(filename string) (ConfigInterface, error) {

internal/config/types.go

@@ -10,6 +10,7 @@ type ZurgConfig struct {
 	CanRepair           bool   `yaml:"enable_repair"`
 	OnLibraryUpdate     string `yaml:"on_library_update"`
 	NetworkBufferSize   int    `yaml:"network_buffer_size"`
+	MountPath           string `yaml:"mount_path"`
 }
 
 func (z *ZurgConfig) GetToken() string {
@@ -55,3 +56,7 @@ func (z *ZurgConfig) GetNetworkBufferSize() int {
 	}
 	return z.NetworkBufferSize
 }
+
+func (z *ZurgConfig) GetMountPath() string {
+	return z.MountPath
+}

internal/mount/mount.go

@@ -0,0 +1,38 @@
+package mount
+
+import (
+	"errors"
+	"log"
+	"os"
+
+	"bazil.org/fuse"
+	"github.com/mdlayher/sdnotify"
+)
+
+func Mount(mountpoint string) error {
+	n, err := sdnotify.New()
+	if err != nil && !errors.Is(err, os.ErrNotExist) {
+		log.Fatalf("failed to open systemd notifier: %v", err)
+	}
+	err = n.Notify(
+		sdnotify.Statusf("service started successfully"),
+		sdnotify.Ready,
+	)
+	if err != nil {
+		log.Fatalf("failed to send ready notification: %v", err)
+	}
+	return Unmount(mountpoint, n)
+}
+
+func Unmount(mountpoint string, n *sdnotify.Notifier) error {
+	log.Println("Unmounting...")
+	err := n.Notify(
+		sdnotify.Statusf("service stopped successfully"),
+		sdnotify.Ready,
+	)
+	if err != nil {
+		log.Fatalf("failed to send stop notification: %v", err)
+	}
+	fuse.Unmount(mountpoint)
+	return nil
+}

internal/torrent/manager.go

@@ -23,26 +23,34 @@ type TorrentManager struct {
 	config            config.ConfigInterface
 	cache             *expirable.LRU[string, string]
 	workerPool        chan bool
-	TorrentDirectoriesMap map[string][]string
+	directoryMap      map[string][]string
 	processedTorrents map[string][]string
+	mu                *sync.Mutex
 }
 
 // NewTorrentManager creates a new torrent manager
 // it will fetch all torrents and their info in the background
-// and store them in-memory
+// and store them in-memory; it is called only once at startup
 func NewTorrentManager(config config.ConfigInterface, cache *expirable.LRU[string, string]) *TorrentManager {
 	t := &TorrentManager{
-		requiredVersion:       "28.10.2023",
+		requiredVersion:   "4.11.2023",
 		config:            config,
 		cache:             cache,
 		workerPool:        make(chan bool, config.GetNumOfWorkers()),
-		TorrentDirectoriesMap: make(map[string][]string),
+		directoryMap:      make(map[string][]string),
 		processedTorrents: make(map[string][]string),
+		mu:                &sync.Mutex{},
 	}
 
 	// Initialize torrents for the first time
+	log.Println("Initializing torrents")
+	t.mu.Lock()
+	log.Println("Fetching torrents")
 	t.torrents = t.getFreshListFromAPI()
 	t.checksum = t.getChecksum()
+	t.mu.Unlock()
+	log.Println("Finished fetching torrents")
+
 	// log.Println("First checksum", t.checksum)
 
 	var wg sync.WaitGroup
@@ -72,7 +80,7 @@ func NewTorrentManager(config config.ConfigInterface, cache *expirable.LRU[strin
 func (t *TorrentManager) GetByDirectory(directory string) []Torrent {
 	var torrents []Torrent
 	for i := range t.torrents {
-		for _, dir := range t.TorrentDirectoriesMap[t.torrents[i].Name] {
+		for _, dir := range t.directoryMap[t.torrents[i].Name] {
 			if dir == directory {
 				torrents = append(torrents, t.torrents[i])
 			}
@@ -195,8 +203,11 @@ func (t *TorrentManager) startRefreshJob() {
 		wg.Wait()
 
 		// apply side effects
+		t.mu.Lock()
 		t.torrents = newTorrents
 		t.checksum = t.getChecksum()
+		t.mu.Unlock()
+
 		// log.Println("Checksum changed", t.checksum)
 		if t.config.EnableRepair() {
 			go t.repairAll(&wg)
@@ -223,6 +234,8 @@ func (t *TorrentManager) getFreshListFromAPI() []Torrent {
 		torrentV2 := Torrent{
 			Torrent:       torrent,
 			SelectedFiles: nil,
+			ForRepair:     false,
+			lock:          &sync.Mutex{},
 		}
 		torrentsV2 = append(torrentsV2, torrentV2)
 
@@ -361,7 +374,7 @@ func (t *TorrentManager) mapToDirectories() {
 					if configV1.MeetsConditions(directory, t.torrents[i].ID, t.torrents[i].Name, filenames) {
 						found := false
 						// check if it is already mapped to this directory
-						for _, dir := range t.TorrentDirectoriesMap[t.torrents[i].Name] {
+						for _, dir := range t.directoryMap[t.torrents[i].Name] {
 							if dir == directory {
 								found = true
 								break // it is already mapped to this directory
@@ -369,12 +382,16 @@ func (t *TorrentManager) mapToDirectories() {
 						}
 						if !found {
 							counter[directory]++
-							t.TorrentDirectoriesMap[t.torrents[i].Name] = append(t.TorrentDirectoriesMap[t.torrents[i].Name], directory)
+							t.mu.Lock()
+							t.directoryMap[t.torrents[i].Name] = append(t.directoryMap[t.torrents[i].Name], directory)
+							t.mu.Unlock()
 							break // we found a directory for this torrent, so we can stop looking for more
 						}
 					}
 				}
+				t.mu.Lock()
 				t.processedTorrents[t.torrents[i].Name] = append(t.processedTorrents[t.torrents[i].Name], group)
+				t.mu.Unlock()
 			}
 			sum := 0
 			for _, count := range counter {
@@ -439,7 +456,6 @@ func (t *TorrentManager) readFromFile(torrentID string) *Torrent {
 	dataDecoder := gob.NewDecoder(file)
 	err = dataDecoder.Decode(&torrent)
 	if err != nil {
-		log.Fatalf("Failed decoding file: %s", err)
 		return nil
 	}
 	if torrent.Version != t.requiredVersion {

internal/torrent/types.go

@@ -1,12 +1,17 @@
 package torrent
 
-import "github.com/debridmediamanager.com/zurg/pkg/realdebrid"
+import (
+	"sync"
+
+	"github.com/debridmediamanager.com/zurg/pkg/realdebrid"
+)
 
 type Torrent struct {
 	Version string
 	realdebrid.Torrent
 	SelectedFiles []File
 	ForRepair     bool
+	lock          *sync.Mutex
 }
 
 type File struct {