(Node.js) IMAP Read PEC Email of Aruba and Extract the Invoice XML Files

IMAP Read PEC Email of Aruba and Extract the Invoice XML Files.

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 imap = new chilkat.Imap();

    // Connect using TLS.
    imap.Ssl = true;
    imap.Port = 993;
    var success = imap.Connect("imap.example.com");
    if (success == false) {
        console.log(imap.LastErrorText);
        return;
    }

    // Authenticate
    success = imap.Login("email_account_login","email_account_password");
    if (success == false) {
        console.log(imap.LastErrorText);
        return;
    }

    // Select an IMAP mailbox
    success = imap.SelectMailbox("Inbox/postacert");
    if (success == false) {
        console.log(imap.LastErrorText);
        return;
    }

    // Search for messages having "POSTA CERTIFICATA: Invio File" in the subject.
    var fetchUids = true;
    // messageSet: MessageSet
    var messageSet = imap.Search("SUBJECT \"POSTA CERTIFICATA: Invio File\"",fetchUids);
    if (imap.LastMethodSuccess == false) {
        console.log(imap.LastErrorText);
        return;
    }

    if (messageSet.Count < 1) {
        console.log("No messages found.");

        return;
    }

    // For our example, we'll process only the 1st email in the messageSet.
    // Download the MIME source of the email into a StringBuilder object.
    // email: Email
    var email = imap.FetchSingle(messageSet.GetId(0),messageSet.HasUids);
    if (imap.LastMethodSuccess == false) {
        console.log(imap.LastErrorText);

        return;
    }

    // The email should contain an attached email.
    // The Invoice XML is contained within the attached email.
    // attachedEmail: Email
    var attachedEmail = email.GetAttachedMessage(0);
    if (email.LastMethodSuccess == false) {
        console.log(email.LastErrorText);

        return;
    }

    // Get the MIME of the attached email..
    var sbMime = new chilkat.StringBuilder();
    success = attachedEmail.GetMimeSb(sbMime);

    // Load it into a Chilkat MIME object.
    var mime = new chilkat.Mime();
    success = mime.LoadMimeSb(sbMime);

    // Examine the structure of the MIME.
    console.log(mime.GetStructure("text"));

    // The MIME has this structure:
    // multipart/mixed
    //     application/octet-stream
    //     application/octet-stream     <-- This is where the XML is contained.   It is within an opaque signature.
    //     text/plain

    // The 2nd application/octet-stream MIME header looks like this:

    // ------=_Part_329673_-1348225228.1579889273592
    // Content-Type: application/octet-stream; name="SM99999_99aaa.xml.p7m"
    // Content-Transfer-Encoding: base64
    // Content-Disposition: attachment; filename="SM99999_99aaa.xml.p7m"

    // Let's get the binary content of the .p7m
    var bdP7m = new chilkat.BinData();
    // Get the 2nd sub-part, at index 1 because index 0 is the 1st sub-part.
    // mimeP7m: Mime
    var mimeP7m = mime.GetPart(1);
    if (mime.LastMethodSuccess !== true) {
        console.log("Failed to get 2nd sub-part. Perhaps the MIME does not have a 2nd sub-part?");
        return;
    }

    success = mimeP7m.GetBodyBd(bdP7m);

    // Verify the signature, which also extracts the content contained within the opaque signature.
    var crypt = new chilkat.Crypt2();
    success = crypt.OpaqueVerifyBd(bdP7m);
    if (success == false) {
        console.log(crypt.LastErrorText);
        return;
    }

    // The bdP7m now contains the Invoice XML.
    // Load it into an XML object.
    var xml = new chilkat.Xml();
    success = xml.LoadBd(bdP7m,true);

    console.log(xml.GetXml());

    // We have XML such as the following:
    // 
    // <?xml version="1.0" encoding="windows-1252"?>
    // <?xml-stylesheet type="text/xsl" href="fatturapa_v1.2.xsl"?>
    // <p:FatturaElettronica versione="FPR12" xmlns:ds="http://www.w3.org/2000/09/xmldsig#" 
    //     xmlns:p="http://ivaservizi.agenziaentrate.gov.it/docs/xsd/fatture/v1.2" 
    //     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    //     <FatturaElettronicaHeader>
    // 	...
    //     </FatturaElettronicaHeader>
    //     <FatturaElettronicaBody>
    // 	...
    //     </FatturaElettronicaBody>
    // </p:FatturaElettronica>

    // Use this online tool to generate parsing code from sample XML: 
    // Generate Parsing Code from XML

    console.log("success.");

}

chilkatExample();