Error encoding UTF-8 characters

[mpldr]

When adding a String with UTF-8 Symbols (for example in Location), it is shown as above.

[vanbroup]

I was able to confirm the issue with this test case:

func TestSignPDFFileUTF8(t *testing.T) {
	certificate_data_block, _ := pem.Decode([]byte(signCertPem))
	if certificate_data_block == nil {
		t.Errorf("failed to parse PEM block containing the certificate")
		return
	}

	cert, err := x509.ParseCertificate(certificate_data_block.Bytes)
	if err != nil {
		t.Errorf("%s", err.Error())
		return
	}

	key_data_block, _ := pem.Decode([]byte(signKeyPem))
	if key_data_block == nil {
		t.Errorf("failed to parse PEM block containing the private key")
		return
	}

	pkey, err := x509.ParsePKCS1PrivateKey(key_data_block.Bytes)
	if err != nil {
		t.Errorf("%s", err.Error())
		return
	}

	tmpfile, err := os.CreateTemp("", "pdfsign_test")
	if err != nil {
		t.Errorf("%s", err.Error())
		return
	}

	signerName := "姓名"
	signerLocation := "位置"
	err = SignFile("../testfiles/testfile20.pdf", tmpfile.Name(), SignData{
		Signature: SignDataSignature{
			Info: SignDataSignatureInfo{
				Name:        signerName,
				Location:    signerLocation,
				Reason:      "Test with UTF-8",
				ContactInfo: "None",
				Date:        time.Now().Local(),
			},
			CertType:   CertificationSignature,
			DocMDPPerm: AllowFillingExistingFormFieldsAndSignaturesPerms,
		},
		DigestAlgorithm: crypto.SHA512,
		Signer:          pkey,
		Certificate:     cert,
	})

	if err != nil {
		os.Remove(tmpfile.Name())
		t.Errorf("%s: %s", "testfile20.pdf", err.Error())
		return
	}

	info, err := verify.File(tmpfile)
	if err != nil {
		t.Errorf("%s: %s", tmpfile.Name(), err.Error())

		err2 := os.Rename(tmpfile.Name(), "../testfiles/failed/testfile20.pdf")
		if err2 != nil {
			t.Error(err2)
		}
	} else {
		if info.Signers[0].Name != signerName {
			t.Errorf("expected %q, got %q", signerName, info.Signers[0].Name)
		}
		if info.Signers[0].Location != signerLocation {
			t.Errorf("expected %q, got %q", signerLocation, info.Signers[0].Location)
		}
		os.Remove(tmpfile.Name())
	}
}

Result:

?       github.com/digitorus/pdfsign    [no test files]
?       github.com/digitorus/pdfsign/revocation [no test files]
?       github.com/digitorus/pdfsign/verify     [no test files]
--- FAIL: TestSignPDFFileUTF8 (0.00s)
    sign_test.go:354: expected "姓名", got "å§fiå’“"
    sign_test.go:357: expected "位置", got "体置"
FAIL
FAIL    github.com/digitorus/pdfsign/sign       0.698s
FAIL

I do need to dive deeper to find what might be causing this.

[vanbroup]

I found a way that should resolve this, but without success, although the test file from the document below doesn't seem to work in my versions of Acrobat eighter.
https://www.pdfa.org/understanding-utf-8-in-pdf-2-0/

Can you try to download this test file and check if the document properties are shown correctly for you?
https://github.com/pdf-association/pdf20examples/raw/master/pdf20-utf8-test.pdf

[vanbroup]

It might actually better to use UTF-16 encoding, I will do some testing with that.

[vanbroup]

Text is now encoded with UTF-16BE encoding when required, this resolved the issue on my side, please check if your issue has been resolved for you as well.