React Native Requires Chilkat v11.0.0+

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

See more Email Object Examples

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

import { BinData, Crypt2, Email, Imap, MessageSet, Mime, StringBuilder, Xml } from '@chilkat/react-native'

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

  const imap = new Imap();

  // Connect using TLS.
  imap.ssl = true;
  imap.port = 993;
  try {
    await imap.connectAsync('imap.example.com');
  } catch {
    console.log(imap.lastErrorText);
    return;
  }

  // Authenticate
  try {
    await imap.loginAsync('email_account_login', 'email_account_password');
  } catch {
    console.log(imap.lastErrorText);
    return;
  }

  // Select an IMAP mailbox
  try {
    await imap.selectMailboxAsync('Inbox/postacert');
  } catch {
    console.log(imap.lastErrorText);
    return;
  }

  // Search for messages having "POSTA CERTIFICATA: Invio File" in the subject.
  const fetchUids = true;
  const messageSet = new MessageSet();
  try {
    await imap.queryMbxAsync('SUBJECT "POSTA CERTIFICATA: Invio File"', fetchUids, messageSet);
  } catch {
    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.
  const email = new Email();
  try {
    await imap.fetchEmailAsync(false, messageSet.getId(0), messageSet.hasUids, email);
  } catch {
    console.log(imap.lastErrorText);
    return;
  }

  // The email should contain an attached email.
  // The Invoice XML is contained within the attached email.
  const attachedEmail = new Email();
  try {
    email.getAttachedEmail(0, attachedEmail);
  } catch {
    console.log(email.lastErrorText);
    return;
  }

  // Get the MIME of the attached email..
  const sbMime = new StringBuilder();
  attachedEmail.getMimeSb(sbMime);

  // Load it into a Chilkat MIME object.
  const mime = new Mime();
  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
  const bdP7m = new BinData();
  // Get the 2nd sub-part, at index 1 because index 0 is the 1st sub-part.

  const mimeP7m = new Mime();
  try {
    mime.partAt(1, mimeP7m);
  } catch {
    console.log(mime.lastErrorText);
    return;
  }

  if (!mime.lastMethodSuccess) {
    console.log('Failed to get 2nd sub-part. Perhaps the MIME does not have a 2nd sub-part?');
    return;
  }

  mimeP7m.getBodyBd(bdP7m);

  // Verify the signature, which also extracts the content contained within the opaque signature.
  const crypt = new Crypt2();
  try {
    crypt.opaqueVerifyBd(bdP7m);
  } catch {
    console.log(crypt.lastErrorText);
    return;
  }

  // The bdP7m now contains the Invoice XML.
  // Load it into an XML object.
  const xml = new Xml();
  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.');
}