Perl

PDF Signature Appearance Text Substitution Keywords

See more PDF Signatures Examples

This example demonstrates the text substitution keywords that can be used in the PDF signature's appearance text.

Note: This example requires Chilkat v9.5.0.85 or greater.

Perl

use chilkat();

$success = 0;

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

$pdf = chilkat::CkPdf->new();

# Load a PDF to be signed.
$success = $pdf->LoadFile("qa_data/pdf/empty.pdf");
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

# Options for signing are specified in JSON.
$json = chilkat::CkJsonObject->new();

# In most cases, the signingCertificateV2 and signingTime attributes are required.
$json->UpdateInt("signingCertificateV2",1);
$json->UpdateInt("signingTime",1);

# Put the signature on page 1, top left
$json->UpdateInt("page",1);
$json->UpdateString("appearance.y","top");
$json->UpdateString("appearance.x","left");

# Use a font scale of 7.0
$json->UpdateString("appearance.fontScale","7.0");

# The appearance of the PDF signature can contain any number of text lines.
# Chilkat has defined a number of special keywords that can be used in any text line.
# Each keyword is replaced with the actual value.
# For example, "cert_cn" is replaced with the certificate subject's common name (CN).

# Here we are creating a signature with many lines of text, to demonstrate each
# keyword.
$json->UpdateString("appearance.text[0]","Date/time in PDF format: current_dt");
$json->UpdateString("appearance.text[1]","Current Local date/time: current_datetime");
$json->UpdateString("appearance.text[2]","GMT Timestamp: current_timestamp_gmt");
$json->UpdateString("appearance.text[3]","Local Timestamp: current_timestamp_local");
$json->UpdateString("appearance.text[4]","GMT RFC822 date/time: current_rfc822_dt_gmt");
$json->UpdateString("appearance.text[5]","Local RFC822 date/time: current_rfc822_dt_local");
$json->UpdateString("appearance.text[6]","Cert DN (Distinguished Name): cert_dn");
$json->UpdateString("appearance.text[7]","Cert Common Name: cert_cn");
$json->UpdateString("appearance.text[8]","Cert Organizational ID (2.5.4.97): cert_org_id");
$json->UpdateString("appearance.text[9]","Cert Email: cert_email");
$json->UpdateString("appearance.text[10]","Cert Organization: cert_organization");
$json->UpdateString("appearance.text[11]","Cert Organziational Unit: cert_ou");
$json->UpdateString("appearance.text[12]","Cert State: cert_state");
$json->UpdateString("appearance.text[13]","Cert Country: cert_country");
$json->UpdateString("appearance.text[14]","Cert Locality: cert_locality");
$json->UpdateString("appearance.text[15]","Cert Serial Number (hex): cert_serial_hex");
$json->UpdateString("appearance.text[16]","Cert Serial Number (decimal): cert_serial_dec");
$json->UpdateString("appearance.text[17]","Cert Thumbprint: cert_thumbprint");
$json->UpdateString("appearance.text[18]","Cert Issuer Common Name: cert_issuer_cn");

$jpgData = chilkat::CkBinData->new();
$success = $jpgData->LoadFile("qa_data/jpg/seal1.jpg");
if ($success == 0) {
    print "Failed to load the JPG image." . "\r\n";
    exit;
}

$success = $pdf->SetSignatureJpeg($jpgData);
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

# Specify that we want to display the JPG image in the center with 33% opacity.
$json->UpdateString("appearance.image","custom-jpg");
$json->UpdateString("appearance.imagePlacement","center");
$json->UpdateString("appearance.imageOpacity","33");

# Load the signing certificate. (Use your own certificate.)
$cert = chilkat::CkCert->new();
$success = $cert->LoadPfxFile("qa_data/pfx/myPdfSigningCert.pfx","pfx_password");
if ($success == 0) {
    print $cert->lastErrorText() . "\r\n";
    exit;
}

# Tell the pdf object to use the certificate for signing.
$success = $pdf->SetSigningCert($cert);
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

$success = $pdf->SignPdf($json,"qa_output/hello_signed.pdf");
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

print "The PDF has been successfully cryptographically signed." . "\r\n";

# The appearance of the signature appears in Adobe Acrobat as shown here:

# (image:https://example-code.com/images/pdf_signature_text_replacements.jpg/endImage)