first commit

filesystem/filesystem.go

@@ -0,0 +1,137 @@
+package filesystem
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+
+	"git.0x0001f346.de/andreas/ablage/config"
+)
+
+func Init() {
+	err := prepareDataFolder()
+	if err != nil {
+		fmt.Println("err")
+		os.Exit(1)
+	}
+
+	err = prepareUploadDir()
+	if err != nil {
+		fmt.Println("err")
+		os.Exit(1)
+	}
+}
+
+func GetHumanReadableSize(bytes int64) string {
+	const unit int64 = 1024
+
+	if bytes < unit {
+		return fmt.Sprintf("%d Bytes", bytes)
+	}
+
+	div, exp := int64(unit), 0
+
+	for n := bytes / unit; n >= unit; n /= unit {
+		div *= unit
+		exp++
+	}
+
+	return fmt.Sprintf("%.1f %cB", float64(bytes)/float64(div), "KMGTPE"[exp])
+}
+
+func SanitizeFilename(dirtyFilename string) string {
+	if dirtyFilename == "" {
+		return "upload.bin"
+	}
+
+	filenameWithoutPath := filepath.Base(dirtyFilename)
+
+	extension := filepath.Ext(filenameWithoutPath)
+	filenameWithoutPathAndExtension := filenameWithoutPath[:len(filenameWithoutPath)-len(extension)]
+
+	cleanedFilename := strings.ReplaceAll(filenameWithoutPathAndExtension, " ", "_")
+	cleanedFilename = strings.ReplaceAll(cleanedFilename, "Ä", "Ae")
+	cleanedFilename = strings.ReplaceAll(cleanedFilename, "ä", "äe")
+	cleanedFilename = strings.ReplaceAll(cleanedFilename, "Ö", "Oe")
+	cleanedFilename = strings.ReplaceAll(cleanedFilename, "ö", "oe")
+	cleanedFilename = strings.ReplaceAll(cleanedFilename, "Ü", "Ue")
+	cleanedFilename = strings.ReplaceAll(cleanedFilename, "ü", "ue")
+	cleanedFilename = strings.ReplaceAll(cleanedFilename, "ß", "ss")
+
+	var safeNameRegex = regexp.MustCompile(`[^a-zA-Z0-9._-]+`)
+	cleanedFilename = safeNameRegex.ReplaceAllString(cleanedFilename, "_")
+
+	for strings.Contains(cleanedFilename, "__") {
+		cleanedFilename = strings.ReplaceAll(cleanedFilename, "__", "_")
+	}
+
+	cleanedFilename = strings.Trim(cleanedFilename, "_")
+
+	const maxLenFilename int = 128
+	if len(cleanedFilename) > maxLenFilename {
+		cleanedFilename = cleanedFilename[:maxLenFilename]
+	}
+
+	return cleanedFilename + extension
+}
+
+func prepareDataFolder() error {
+	info, err := os.Stat(config.GetPathDataFolder())
+	if os.IsNotExist(err) {
+		if err := os.Mkdir(config.GetPathDataFolder(), 0755); err != nil {
+			return fmt.Errorf("Error: Could not create folder '%s': %v", config.GetPathDataFolder(), err)
+		}
+	} else if err != nil {
+		return fmt.Errorf("Error: Could not access '%s': %v", config.GetPathDataFolder(), err)
+	} else if !info.IsDir() {
+		return fmt.Errorf("Error: '%s' exists but is not a directory", config.GetPathDataFolder())
+	}
+
+	pathTestFile := filepath.Join(config.GetPathDataFolder(), ".write_test")
+	err = os.WriteFile(pathTestFile, []byte("test"), 0644)
+	if err != nil {
+		return fmt.Errorf("Error: Could not create test file '%s': %v", pathTestFile, err)
+	}
+
+	err = os.Remove(pathTestFile)
+	if err != nil {
+		return fmt.Errorf("Error: Could not delete test file '%s': %v", pathTestFile, err)
+	}
+
+	return nil
+}
+
+func prepareUploadDir() error {
+	info, err := os.Stat(config.GetPathUploadFolder())
+	if err == nil {
+		if !info.IsDir() {
+			return fmt.Errorf("%s exists, but is not a folder", config.GetPathUploadFolder())
+		}
+
+		err = os.RemoveAll(config.GetPathUploadFolder())
+		if err != nil {
+			return fmt.Errorf("Error: Could not delete upload folder '%s': %v", config.GetPathUploadFolder(), err)
+		}
+	} else if !os.IsNotExist(err) {
+		return fmt.Errorf("Error: '%s' exists but is somewhat broken", config.GetPathUploadFolder())
+	}
+
+	if err := os.MkdirAll(config.GetPathUploadFolder(), 0755); err != nil {
+		return fmt.Errorf("Error: Could not create upload folder '%s': %v", config.GetPathUploadFolder(), err)
+	}
+
+	pathTestFile := filepath.Join(config.GetPathUploadFolder(), ".write_test")
+	err = os.WriteFile(pathTestFile, []byte("test"), 0644)
+	if err != nil {
+		return fmt.Errorf("Error: Could not create test file '%s': %v", pathTestFile, err)
+	}
+
+	err = os.Remove(pathTestFile)
+	if err != nil {
+		return fmt.Errorf("Error: Could not delete test file '%s': %v", pathTestFile, err)
+	}
+
+	return nil
+}