(Node.js) Duplicate openssl pkey -in private.pem -pubout -out pubkey.pem

How to output the public part of a private key: Demonstrates how to duplicate this OpenSSL command:

openssl pkey -in private.pem -pubout -out pubkey.pem

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() {

    var pkey = new chilkat.PrivateKey();

    // Load the private key from an PEM file:
    var success = pkey.LoadPemFile("private.pem");
    if (success !== true) {
        console.log(pkey.LastErrorText);
        return;
    }

    // pubKey: PublicKey
    var pubKey = pkey.GetPublicKey();
    if (pkey.LastMethodSuccess == false) {
        console.log(pkey.LastErrorText);
        return;
    }

    success = pubKey.SavePemFile(false,"pubKey.pem");
    if (success !== true) {
        console.log(pubKey.LastErrorText);

        return;
    }

    console.log("Success.");


}

chilkatExample();