golden/pdfxform a pdf rasterization server

go/pdf/pdf_test.go

Index: go/pdf/pdf_test.go
diff --git a/go/pdf/pdf_test.go b/go/pdf/pdf_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..526d2794cedcfcdcabb9afe7426ba46b7fa39108
--- /dev/null
+++ b/go/pdf/pdf_test.go
@@ -0,0 +1,87 @@
+package pdf
+
+import (
+	"bytes"
+	"crypto/md5"
+	"io"
+	"io/ioutil"
+	"os"
+	"path"
+	"testing"
+
+	"github.com/skia-dev/glog"
+	assert "github.com/stretchr/testify/require"
+	"go.skia.org/infra/go/fileutil"
+	"go.skia.org/infra/go/testutils"
+	"go.skia.org/infra/go/util"
+)
+
+func md5OfFile(path string) (sum []byte, err error) {
+	md5 := md5.New()
+	f, err := os.Open(path)
+	if err != nil {
+		return
+	}
+	defer util.Close(f)
+	if _, err = io.Copy(md5, f); err != nil {
+		return
+	}
+	sum = md5.Sum(nil)
+	return
+}
+
+func filesEqual(path1, path2 string) bool {
+	checksum1, err := md5OfFile(path1)
+	if err != nil {
+		glog.Infof("%v\n", err)
+		return false
+	}
+	checksum2, err := md5OfFile(path2)
+	if err != nil {
+		glog.Infof("%v\n", err)
+		return false
+	}
+	return 0 == bytes.Compare(checksum1, checksum2)
+}
+
+func testRasterizer(t *testing.T, rasterizer Rasterizer, expectation string) {
+	assert.True(t, rasterizer.Enabled(), "%s.Enabled() failed.", rasterizer.String())
+
+	testDataDir, err := testutils.TestDataDir()
+	assert.Nil(t, err, "TestDataDir missing: %v", err)
+
+	tempDir, err := ioutil.TempDir("", "pdf_test_")
+	assert.Nil(t, err, "ioutil.TempDir failed")
+	defer util.RemoveAll(tempDir)
+
+	pdfSrcPath := path.Join(testDataDir, "minimal.pdf")
+	assert.True(t, fileutil.FileExists(pdfSrcPath), "Path '%s' does not exist", pdfSrcPath)
+	pdfInputPath := path.Join(tempDir, "minimal.pdf")
+
+	err = os.Symlink(pdfSrcPath, pdfInputPath)
+	assert.Nil(t, err, "Symlink failed")
+	assert.True(t, fileutil.FileExists(pdfInputPath), "Path '%s' does not exist", pdfInputPath)
+
+	outputFileName := path.Join(tempDir, "test.png")
+
+	badPath := path.Join(tempDir, "this_file_should_really_not_exist.pdf")
+
+	if err := rasterizer.Rasterize(badPath, outputFileName); err == nil {
+		t.Errorf(": Got '%v' Want '%v'", err, nil)
+	}
+
+	if err := rasterizer.Rasterize(pdfInputPath, outputFileName); err != nil {
+		t.Errorf(": Got '%v' Want '!nil'", err)
+	}
+
+	expectedOutput := path.Join(testDataDir, expectation)
+	assert.True(t, filesEqual(outputFileName, expectedOutput), "png output not correct")
+}
+
+func TestRasterizePdfium(t *testing.T) {
+	testRasterizer(t, Pdfium{}, "minimalPdfium.png")
+}
+
+func TestRasterizePoppler(t *testing.T) {
+	testRasterizer(t, Poppler{}, "minimalPoppler.png")
+}