(Node.js) Canonicalize XML Fragment

Demonstrates how to canonicalize a fragment of an XML document. The fragment is identified by the element having an Id attribute equal to a specified value. (The Id attribute can have any namespace, and the attribute name is case-insensitive (thus "ID", "Id", "id", etc. match).

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

var os = require('os');
if (os.platform() == 'win32') {  
    if (os.arch() == 'ia32') {
        var chilkat = require('@chilkat/ck-node21-win-ia32');
    } else {
        var chilkat = require('@chilkat/ck-node21-win64'); 
    }
} else if (os.platform() == 'linux') {
    if (os.arch() == 'arm') {
        var chilkat = require('@chilkat/ck-node21-arm');
    } else if (os.arch() == 'x86') {
        var chilkat = require('@chilkat/ck-node21-linux32');
    } else {
        var chilkat = require('@chilkat/ck-node21-linux64');
    }
} else if (os.platform() == 'darwin') {
    if (os.arch() == 'arm64') {
        var chilkat = require('@chilkat/ck-node21-mac-m1');
    } else {
        var chilkat = require('@chilkat/ck-node21-macosx');
    }
}

function chilkatExample() {

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

    var http = new chilkat.Http();
    var sbXml = new chilkat.StringBuilder();
    var canon = new chilkat.XmlDSig();

    // Use exclusive XML canonicalization.
    var canonVersion = "EXCL_C14N";
    var withComments = false;
    // The optional inclusive namespaces prefix list if using exclusive canonicalization.
    var prefixList = "";

    var url = "https://www.chilkatsoft.com/exampleData/canonicalizeFragmentTest.xml";
    var success = http.QuickGetSb(url,sbXml);

    // This is the input XML:

    // <?xml version="1.0" encoding="UTF-8"?>
    // <Signature xmlns="http://www.w3.org/2000/09/xmldsig#">
    // <SignedInfo>
    //   <CanonicalizationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315" />
    //   <SignatureMethod Algorithm="http://www.w3.org/2000/09/xmldsig#rsa-sha1" />
    //   <Reference URI="#object">
    //     <DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1" />
    //     <DigestValue>OPnpF/ZNLDxJ/I+1F3iHhlmSwgo=</DigestValue>
    //   </Reference>
    // </SignedInfo>
    // <SignatureValue>nihUFQg4mDhLgecvhIcKb9Gz8VRTOlw+adiZOBBXgK4JodEe5aFfCqm8WcRIT8GL
    // LXSk8PsUP4//SsKqUBQkpotcAqQAhtz2v9kCWdoUDnAOtFZkd/CnsZ1sge0ndha4
    // 0wWDV+nOWyJxkYgicvB8POYtSmldLLepPGMz+J7/Uws=</SignatureValue>
    // <KeyInfo>
    //   <KeyValue>
    //     <RSAKeyValue>
    //       <Modulus>4IlzOY3Y9fXoh3Y5f06wBbtTg94Pt6vcfcd1KQ0FLm0S36aGJtTSb6pYKfyX7PqC
    //       UQ8wgL6xUJ5GRPEsu9gyz8ZobwfZsGCsvu40CWoT9fcFBZPfXro1Vtlh/xl/yYHm
    //       +Gzqh0Bw76xtLHSfLfpVOrmZdwKmSFKMTvNXOFd0V18=</Modulus>
    //       <Exponent>AQAB</Exponent>
    //     </RSAKeyValue>
    //   </KeyValue>
    // </KeyInfo>
    // <Object Id="object">some text
    //   with spaces and CR-LF.</Object>
    // </Signature>

    // Canonicalize and return the fragment of XML starting at the element where the Id attribute equals "object".
    var xmlCanonFrag = canon.CanonicalizeFragment(sbXml.GetAsString(),"object",canonVersion,prefixList,withComments);
    console.log(xmlCanonFrag);

    // The output is:
    // 
    // <Object xmlns="http://www.w3.org/2000/09/xmldsig#" Id="object">some text
    //   with spaces and CR-LF.</Object>
    // 

}

chilkatExample();