feat(erase): add db/all subcommands with db as default

Add selective deletion to erase command:
- 'db' (default): clear only database
- 'all': clear database and song files

Updated README and help messages with new usage examples.

README.md

@@ -95,7 +95,12 @@ go run *.go find <path-to-wav-file>
 ```
 #### ▸ Delete fingerprints and songs 🗑️ 
 ```
+# Delete only database (default)
 go run *.go erase
+go run *.go erase db
+
+# Delete both database and song files
+go run *.go erase all
 ```
 
 ## Example :film_projector:  

server/cmdHandlers.go

@@ -199,7 +199,7 @@ func serveHTTP(socketServer *socketio.Server, serveHTTPS bool, port string) {
 	}
 }
 
-func erase(songsDir string) {
+func erase(songsDir string, dbOnly bool, all bool) {
 	logger := utils.GetLogger()
 	ctx := context.Background()
 
@@ -222,26 +222,31 @@ func erase(songsDir string) {
 		logger.ErrorContext(ctx, msg, slog.Any("error", err))
 	}
 
-	// delete song files
-	err = filepath.Walk(songsDir, func(path string, info os.FileInfo, err error) error {
-		if err != nil {
-			return err
-		}
+	fmt.Println("Database cleared")
 
-		if !info.IsDir() {
-			ext := filepath.Ext(path)
-			if ext == ".wav" || ext == ".m4a" {
-				err := os.Remove(path)
-				if err != nil {
-					return err
+	// delete song files only if -all flag is set
+	if all {
+		err = filepath.Walk(songsDir, func(path string, info os.FileInfo, err error) error {
+			if err != nil {
+				return err
+			}
+
+			if !info.IsDir() {
+				ext := filepath.Ext(path)
+				if ext == ".wav" || ext == ".m4a" {
+					err := os.Remove(path)
+					if err != nil {
+						return err
+					}
 				}
 			}
+			return nil
+		})
+		if err != nil {
+			msg := fmt.Sprintf("Error walking through directory %s: %v\n", songsDir, err)
+			logger.ErrorContext(ctx, msg, slog.Any("error", err))
 		}
-		return nil
-	})
-	if err != nil {
-		msg := fmt.Sprintf("Error walking through directory %s: %v\n", songsDir, err)
-		logger.ErrorContext(ctx, msg, slog.Any("error", err))
+		fmt.Println("Songs folder cleared")
 	}
 
 	fmt.Println("Erase complete")

server/main.go

@@ -8,8 +8,8 @@ import (
 	"os"
 	"song-recognition/utils"
 
-	"github.com/mdobak/go-xerrors"
 	"github.com/joho/godotenv"
+	"github.com/mdobak/go-xerrors"
 )
 
 func main() {
@@ -32,10 +32,16 @@ func main() {
 
 	if len(os.Args) < 2 {
 		fmt.Println("Expected 'find', 'download', 'erase', 'save', or 'serve' subcommands")
+		fmt.Println("\nUsage examples:")
+		fmt.Println("  find <path_to_wav_file>")
+		fmt.Println("  download <spotify_url>")
+		fmt.Println("  erase [db | all]  (default: db)")
+		fmt.Println("  save [-f|--force] <path_to_file_or_dir>")
+		fmt.Println("  serve [-proto <http|https>] [-p <port>]")
 		os.Exit(1)
 	}
 	_ = godotenv.Load()
-	
+
 	switch os.Args[1] {
 	case "find":
 		if len(os.Args) < 3 {
@@ -58,7 +64,28 @@ func main() {
 		serveCmd.Parse(os.Args[2:])
 		serve(*protocol, *port)
 	case "erase":
-		erase(SONGS_DIR)
+		// Default is to clear only database (db mode)
+		dbOnly := true
+		all := false
+
+		if len(os.Args) > 2 {
+			subCmd := os.Args[2]
+			switch subCmd {
+			case "db":
+				dbOnly = true
+				all = false
+			case "all":
+				dbOnly = false
+				all = true
+			default:
+				fmt.Println("Usage: main.go erase [db | all]")
+				fmt.Println("  db  : only clear the database (default)")
+				fmt.Println("  all : clear database and songs folder")
+				os.Exit(1)
+			}
+		}
+
+		erase(SONGS_DIR, dbOnly, all)
 	case "save":
 		indexCmd := flag.NewFlagSet("save", flag.ExitOnError)
 		force := indexCmd.Bool("force", false, "save song with or without YouTube ID")
@@ -72,6 +99,12 @@ func main() {
 		save(filePath, *force)
 	default:
 		fmt.Println("Expected 'find', 'download', 'erase', 'save', or 'serve' subcommands")
+		fmt.Println("\nUsage examples:")
+		fmt.Println("  find <path_to_wav_file>")
+		fmt.Println("  download <spotify_url>")
+		fmt.Println("  erase [db | all]  (default: db)")
+		fmt.Println("  save [-f|--force] <path_to_file_or_dir>")
+		fmt.Println("  serve [-proto <http|https>] [-p <port>]")
 		os.Exit(1)
 	}
 }