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Node.js

Sign PDF with Invisible Signature

See more PDF Signatures Examples

Demonstrates how to sign a PDF with an invisible signature.

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

Chilkat Node.js Downloads

Node.js
NODEJS_PRELUDE

function chilkatExample() {

    var success = false;

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

    var pdf = new chilkat.Pdf();

    //  Load a PDF to be signed.
    //  The "hello.pdf" is available at https://chilkatsoft.com/hello.pdf
    success = pdf.LoadFile("qa_data/pdf/hello.pdf");
    if (success == false) {
        console.log(pdf.LastErrorText);
        return;
    }

    //  Options for signing are specified in JSON.
    var json = new chilkat.JsonObject();

    //  In most cases, the signingCertificateV2 and signingTime attributes are required.
    json.UpdateInt("signingCertificateV2",1);
    json.UpdateInt("signingTime",1);

    //  Indicate that the signature will be invisible.
    json.UpdateBool("invisibleSignature",true);

    //  Load the signing certificate. (Use your own certificate.)
    var cert = new chilkat.Cert();
    success = cert.LoadPfxFile("qa_data/pfx/myPdfSigningCert.pfx","secret");
    if (success == false) {
        console.log(cert.LastErrorText);
        return;
    }

    //  Tell the pdf object to use the certificate for signing.
    success = pdf.SetSigningCert(cert);
    if (success == false) {
        console.log(pdf.LastErrorText);
        return;
    }

    success = pdf.SignPdf(json,"qa_output/hello_signed.pdf");
    if (success == false) {
        console.log(pdf.LastErrorText);
        return;
    }

    console.log("PDF successfully signed with an invisible signature.");

    //  An invisible signature has no appearance within the PDF document itself,
    //  but Adobe Acrobat will indicate the document is signed in a toolbar, as shown here:
    //  (image:https://example-code.com/images/invisible_signature.jpg/endImage)

}

chilkatExample();