feat(pdfengines): add PDF/UA (#714)

pkg/modules/pdfcpu/doc.go

@@ -1,4 +1,6 @@
-// Package pdfcpu provides a module which wraps the
-// https://github.com/pdfcpu/pdfcpu library and implements the
-// gotenberg.PDFEngine interface.
+// Package pdfcpu provides an implementation of the gotenberg.PdfEngine
+// interface using the pdfcpu library. This package allows for the merging of
+// PDF files but does not support conversion to specific PDF formats.
+//
+// See: https://github.com/pdfcpu/pdfcpu.
 package pdfcpu

pkg/modules/pdfcpu/pdfcpu.go

@@ -13,35 +13,34 @@ import (
 )
 
 func init() {
-	gotenberg.MustRegisterModule(PDFcpu{})
+	gotenberg.MustRegisterModule(new(PdfCpu))
 }
 
-// PDFcpu is a module which wraps the https://github.com/pdfcpu/pdfcpu library
-// and implements the gotenberg.PDFEngine interface.
-type PDFcpu struct {
+// PdfCpu abstracts the pdfcpu library and implements the [gotenberg.PdfEngine]
+// interface.
+type PdfCpu struct {
 	conf *pdfcpuConfig.Configuration
 }
 
-// Descriptor returns a PDFcpu's module descriptor.
-func (PDFcpu) Descriptor() gotenberg.ModuleDescriptor {
+// Descriptor returns a [PdfCpu]'s module descriptor.
+func (engine *PdfCpu) Descriptor() gotenberg.ModuleDescriptor {
 	return gotenberg.ModuleDescriptor{
 		ID:  "pdfcpu",
-		New: func() gotenberg.Module { return new(PDFcpu) },
+		New: func() gotenberg.Module { return new(PdfCpu) },
 	}
 }
 
 // Provision sets the engine properties.
-func (engine *PDFcpu) Provision(_ *gotenberg.Context) error {
+func (engine *PdfCpu) Provision(ctx *gotenberg.Context) error {
 	pdfcpuConfig.ConfigPath = "disable"
 	pdfcpuLog.DisableLoggers()
-
 	engine.conf = pdfcpuConfig.NewDefaultConfiguration()
 
 	return nil
 }
 
-// Merge merges the given PDFs into a unique Pdf.
-func (engine PDFcpu) Merge(_ context.Context, _ *zap.Logger, inputPaths []string, outputPath string) error {
+// Merge combines multiple PDFs into a single PDF.
+func (engine *PdfCpu) Merge(ctx context.Context, logger *zap.Logger, inputPaths []string, outputPath string) error {
 	err := pdfcpuAPI.MergeCreateFile(inputPaths, outputPath, engine.conf)
 	if err == nil {
 		return nil
@@ -50,14 +49,14 @@ func (engine PDFcpu) Merge(_ context.Context, _ *zap.Logger, inputPaths []string
 	return fmt.Errorf("merge PDFs with PDFcpu: %w", err)
 }
 
-// Convert is not available for this Pdf engine.
-func (engine PDFcpu) Convert(_ context.Context, _ *zap.Logger, format, _, _ string) error {
-	return fmt.Errorf("convert Pdf to '%s' with PDFcpu: %w", format, gotenberg.ErrPDFEngineMethodNotAvailable)
+// Convert is not available in this implementation.
+func (engine *PdfCpu) Convert(ctx context.Context, logger *zap.Logger, formats gotenberg.PdfFormats, inputPath, outputPath string) error {
+	return fmt.Errorf("convert PDF to '%+v' with PDFcpu: %w", formats, gotenberg.ErrPdfEngineMethodNotSupported)
 }
 
 // Interface guards.
 var (
-	_ gotenberg.Module      = (*PDFcpu)(nil)
-	_ gotenberg.Provisioner = (*PDFcpu)(nil)
-	_ gotenberg.PDFEngine   = (*PDFcpu)(nil)
+	_ gotenberg.Module      = (*PdfCpu)(nil)
+	_ gotenberg.Provisioner = (*PdfCpu)(nil)
+	_ gotenberg.PdfEngine   = (*PdfCpu)(nil)
 )

pkg/modules/pdfcpu/pdfcpu_test.go

@@ -12,89 +12,93 @@ import (
 	"github.com/gotenberg/gotenberg/v7/pkg/gotenberg"
 )
 
-func TestPDFcpu_Descriptor(t *testing.T) {
-	descriptor := PDFcpu{}.Descriptor()
+func TestPdfCpu_Descriptor(t *testing.T) {
+	descriptor := new(PdfCpu).Descriptor()
 
 	actual := reflect.TypeOf(descriptor.New())
-	expect := reflect.TypeOf(new(PDFcpu))
+	expect := reflect.TypeOf(new(PdfCpu))
 
 	if actual != expect {
 		t.Errorf("expected '%s' but got '%s'", expect, actual)
 	}
 }
 
-func TestPDFcpu_Provision(t *testing.T) {
-	mod := new(PDFcpu)
+func TestPdfCpu_Provision(t *testing.T) {
+	engine := new(PdfCpu)
 	ctx := gotenberg.NewContext(gotenberg.ParsedFlags{}, nil)
 
-	err := mod.Provision(ctx)
+	err := engine.Provision(ctx)
 	if err != nil {
 		t.Errorf("expected no error but got: %v", err)
 	}
 }
 
-func TestPDFcpu_Merge(t *testing.T) {
-	for i, tc := range []struct {
-		inputPaths []string
-		expectErr  bool
+func TestPdfCpu_Merge(t *testing.T) {
+	for _, tc := range []struct {
+		scenario    string
+		inputPaths  []string
+		expectError bool
 	}{
 		{
+			scenario: "invalid input path",
+			inputPaths: []string{
+				"foo",
+			},
+			expectError: true,
+		},
+		{
+			scenario: "single file success",
 			inputPaths: []string{
 				"/tests/test/testdata/pdfengines/sample1.pdf",
 			},
+			expectError: false,
 		},
 		{
+			scenario: "many files success",
 			inputPaths: []string{
 				"/tests/test/testdata/pdfengines/sample1.pdf",
 				"/tests/test/testdata/pdfengines/sample2.pdf",
 			},
 		},
-		{
-			inputPaths: []string{
-				"foo",
-			},
-			expectErr: true,
-		},
 	} {
-		func() {
-			mod := new(PDFcpu)
-
-			err := mod.Provision(nil)
+		t.Run(tc.scenario, func(t *testing.T) {
+			engine := new(PdfCpu)
+			err := engine.Provision(nil)
 			if err != nil {
-				t.Fatalf("test %d: expected error but got: %v", i, err)
+				t.Fatalf("expected error but got: %v", err)
 			}
 
 			fs := gotenberg.NewFileSystem()
 			outputDir, err := fs.MkdirAll()
 			if err != nil {
-				t.Fatalf("test %d: expected error but got: %v", i, err)
+				t.Fatalf("expected error but got: %v", err)
 			}
 
 			defer func() {
-				err := os.RemoveAll(fs.WorkingDirPath())
+				err = os.RemoveAll(fs.WorkingDirPath())
 				if err != nil {
-					t.Fatalf("test %d: expected no error while cleaning up but got: %v", i, err)
+					t.Fatalf("expected no error while cleaning up but got: %v", err)
 				}
 			}()
 
-			err = mod.Merge(nil, nil, tc.inputPaths, outputDir+"/foo.pdf")
+			err = engine.Merge(nil, nil, tc.inputPaths, outputDir+"/foo.pdf")
 
-			if tc.expectErr && err == nil {
-				t.Errorf("test %d: expected error but got: %v", i, err)
+			if !tc.expectError && err != nil {
+				t.Fatalf("expected no error but got: %v", err)
 			}
 
-			if !tc.expectErr && err != nil {
-				t.Errorf("test %d: expected no error but got: %v", i, err)
+			if tc.expectError && err == nil {
+				t.Fatal("expected error but got none")
 			}
-		}()
+		})
 	}
 }
 
-func TestPDFcpu_Convert(t *testing.T) {
-	mod := new(PDFcpu)
-	err := mod.Convert(context.TODO(), zap.NewNop(), "", "", "")
+func TestPdfCpu_Convert(t *testing.T) {
+	mod := new(PdfCpu)
+	err := mod.Convert(context.TODO(), zap.NewNop(), gotenberg.PdfFormats{}, "", "")
 
-	if !errors.Is(err, gotenberg.ErrPDFEngineMethodNotAvailable) {
-		t.Errorf("expected error %v, but got: %v", gotenberg.ErrPDFEngineMethodNotAvailable, err)
+	if !errors.Is(err, gotenberg.ErrPdfEngineMethodNotSupported) {
+		t.Errorf("expected error %v, but got: %v", gotenberg.ErrPdfEngineMethodNotSupported, err)
 	}
 }