Swift
Calculate HRMC IRMark

See more XML Digital Signatures Examples
Demonstrates how to calculate an IRmark for an HMRC GovTalkMessage XML document.
Chilkat Swift Downloads

Swift

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

    // First build a sample (but incomplete) GovTalkMessage.
    // You can replace this code with a call to LoadXml or LoadXmlFile..
    // 
    // Note: The online tool at https://tools.chilkat.io/xmlCreate.cshtml
    // can be used to generate XML code that creates a given XML document.
    let xml = CkoXml()!
    xml.tag = "GovTalkMessage"
    xml.addAttribute(name: "xmlns", value: "http://www.govtalk.gov.uk/CM/envelope")
    xml.updateAttrAt(tagPath: "Body|Message", autoCreate: true, attrName: "xmlns", attrValue: "urn:g3.ge:dea:call:SendDocument:v1")
    xml.updateChildContent(tagPath: "Body|Message", value: "................")

    // This is the XML created:
    // <?xml version="1.0" encoding="utf-8" ?>
    // <GovTalkMessage xmlns="http://www.govtalk.gov.uk/CM/envelope">
    //     <Body>
    //         <Message xmlns="urn:g3.ge:dea:call:SendDocument:v1">................</Message>
    //     </Body>
    // </GovTalkMessage>

    print("\(xml.getXml()!)")

    // Canonicalize the XML (using C14N)
    let xdsig = CkoXmlDSig()!
    var withComments: Bool = false
    var canonXml: String? = xdsig.canonicalizeXml(xml: xml.getXml(), version: "C14N", withComments: withComments)

    // Return the base64 SHA-1 HASH of the canonical XML.
    let crypt = CkoCrypt2()!
    crypt.hashAlgorithm = "sha1"
    crypt.encodingMode = "base64"
    var irmark: String? = crypt.hashStringENC(str: canonXml)

    print("IRMark = \(irmark!)")

}