Adding upstream version 0.28.1.

Signed-off-by: Daniel Baumann <daniel@debian.org>

core/validators/file.go

@@ -0,0 +1,96 @@
+package validators
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/gabriel-vasile/mimetype"
+	validation "github.com/go-ozzo/ozzo-validation/v4"
+	"github.com/pocketbase/pocketbase/tools/filesystem"
+)
+
+// UploadedFileSize checks whether the validated [*filesystem.File]
+// size is no more than the provided maxBytes.
+//
+// Example:
+//
+//	validation.Field(&form.File, validation.By(validators.UploadedFileSize(1000)))
+func UploadedFileSize(maxBytes int64) validation.RuleFunc {
+	return func(value any) error {
+		v, ok := value.(*filesystem.File)
+		if !ok {
+			return ErrUnsupportedValueType
+		}
+
+		if v == nil {
+			return nil // nothing to validate
+		}
+
+		if v.Size > maxBytes {
+			return validation.NewError(
+				"validation_file_size_limit",
+				"Failed to upload {{.file}} - the maximum allowed file size is {{.maxSize}} bytes.",
+			).SetParams(map[string]any{
+				"file":    v.OriginalName,
+				"maxSize": maxBytes,
+			})
+		}
+
+		return nil
+	}
+}
+
+// UploadedFileMimeType checks whether the validated [*filesystem.File]
+// mimetype is within the provided allowed mime types.
+//
+// Example:
+//
+//	validMimeTypes := []string{"test/plain","image/jpeg"}
+//	validation.Field(&form.File, validation.By(validators.UploadedFileMimeType(validMimeTypes)))
+func UploadedFileMimeType(validTypes []string) validation.RuleFunc {
+	return func(value any) error {
+		v, ok := value.(*filesystem.File)
+		if !ok {
+			return ErrUnsupportedValueType
+		}
+
+		if v == nil {
+			return nil // nothing to validate
+		}
+
+		baseErr := validation.NewError(
+			"validation_invalid_mime_type",
+			fmt.Sprintf("Failed to upload %q due to unsupported file type.", v.OriginalName),
+		)
+
+		if len(validTypes) == 0 {
+			return baseErr
+		}
+
+		f, err := v.Reader.Open()
+		if err != nil {
+			return baseErr
+		}
+		defer f.Close()
+
+		filetype, err := mimetype.DetectReader(f)
+		if err != nil {
+			return baseErr
+		}
+
+		for _, t := range validTypes {
+			if filetype.Is(t) {
+				return nil // valid
+			}
+		}
+
+		return validation.NewError(
+			"validation_invalid_mime_type",
+			fmt.Sprintf(
+				"%q mime type must be one of: %s.",
+				v.Name,
+				strings.Join(validTypes, ", "),
+			),
+		)
+	}
+}