(Node.js) Get PDF Signer Certs

See more PDF Signatures Examples

This example demonstrates how to validate the signatures in a PDF and also shows how to get each signature's signer certificate.

Note: This example requires Chilkat v9.5.0.87 or greater.

Install Chilkat for Node.js and Electron using npm at Chilkat npm packages for Node.js Chilkat npm packages for Electron on Windows, Linux, MacOS

var os = require('os');
if (os.platform() == 'win32') {  
  var chilkat = require('@chilkat/ck-node23-win64'); 
} else if (os.platform() == 'linux') {
    if (os.arch() == 'arm') {
        var chilkat = require('@chilkat/ck-node23-linux-arm');
    } else if (os.arch() == 'arm64') {
        var chilkat = require('@chilkat/ck-node23-linux-arm64');
    } else {
        var chilkat = require('@chilkat/ck-node23-linux-x64');
    }
} else if (os.platform() == 'darwin') {
  var chilkat = require('@chilkat/ck-node23-mac-universal');
}

function chilkatExample() {

    // 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 that has cryptographic signatures to be validated
    var success = pdf.LoadFile("qa_data/pdf/sign_testing_1/helloSigned2.pdf");
    if (success == false) {
        console.log(pdf.LastErrorText);
        return;
    }

    // Each time we verify a signature, information about the signature is written into
    // sigInfo (replacing whatever sigInfo previously contained).
    var sigInfo = new chilkat.JsonObject();

    // Iterate over each signature and validate each.
    var numSignatures = pdf.NumSignatures;
    var validated = false;
    var cert = new chilkat.Cert();
    var i = 0;
    while (i < numSignatures) {
        validated = pdf.VerifySignature(i,sigInfo);
        console.log("Signature " + i + " validated: " + validated);

        // The GetSignerCert method was added in Chilkat v9.5.0.87
        // After calling VerifySignature, you can get the signer certificate by calling
        // GetSignerCert with the same index. 
        success = pdf.GetSignerCert(i,cert);
        if (success !== false) {
            console.log("PDF signer certificate: " + cert.SubjectDN);
        }

        i = i+1;
    }

    console.log("Finished.");

}

chilkatExample();