chore(deps): update pdfcpu to v0.15.0 (#1628)

pkg/modules/qpdf/qpdf.go

@@ -419,17 +419,57 @@ func (engine *QPdf) Encrypt(ctx context.Context, logger *slog.Logger, inputPath
 }
 
 // EmbedFiles is not available in this implementation.
+// EmbedFiles embeds the given files into a PDF as attachments using qpdf's
+// --add-attachment. It is a fallback for pdfcpu: qpdf reads PDFs whose document
+// info pdfcpu's stricter validation rejects (for example a non-conformant
+// /Trapped value written by ExifTool). See
+// https://github.com/gotenberg/gotenberg/issues/1628.
 func (engine *QPdf) EmbedFiles(ctx context.Context, logger *slog.Logger, filePaths []string, inputPath string) error {
-	_, span := gotenberg.Tracer().Start(ctx, "qpdf.EmbedFiles",
+	ctx, span := gotenberg.Tracer().Start(ctx, "qpdf.EmbedFiles",
 		trace.WithSpanKind(trace.SpanKindClient),
 		trace.WithAttributes(engine.spanAttrs()...),
 	)
 	defer span.End()
 
-	err := fmt.Errorf("embed files with QPDF: %w", gotenberg.ErrPdfEngineMethodNotSupported)
-	span.RecordError(err)
-	span.SetStatus(codes.Error, err.Error())
-	return err
+	if len(filePaths) == 0 {
+		span.SetStatus(codes.Ok, "")
+		return nil
+	}
+
+	fail := func(err error) error {
+		span.RecordError(err)
+		span.SetStatus(codes.Error, err.Error())
+		return err
+	}
+
+	// Each --add-attachment group must be terminated by "--", so qpdf attaches
+	// one file per invocation. Chain them, writing to a temporary file and
+	// moving it back over the input each time.
+	outputPath := inputPath + "~embed"
+	for _, filePath := range filePaths {
+		args := make([]string, 0, 6+len(engine.globalArgs))
+		args = append(args, engine.globalArgs...)
+		args = append(args, "--add-attachment", filePath, "--key="+filepath.Base(filePath))
+		args = append(args, "--", inputPath, outputPath)
+
+		cmd, err := gotenberg.CommandContext(ctx, logger, engine.binPath, args...)
+		if err != nil {
+			return fail(fmt.Errorf("create command: %w", err))
+		}
+
+		_, err = cmd.Exec()
+		if err != nil {
+			return fail(fmt.Errorf("embed files with QPDF: %w", err))
+		}
+
+		err = os.Rename(outputPath, inputPath)
+		if err != nil {
+			return fail(fmt.Errorf("embed files with QPDF: replace input: %w", err))
+		}
+	}
+
+	span.SetStatus(codes.Ok, "")
+	return nil
 }
 
 // EmbedFilesMetadata sets metadata on already-embedded files in a PDF using