Java

Send DKIM Signed Email

See more DKIM / DomainKey Examples

Demonstrates how to send DKIM signed email. Chilkat2 Java

import com.chilkatsoft.chilkat2.BinData;
import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.Dkim;
import com.chilkatsoft.chilkat2.Email;
import com.chilkatsoft.chilkat2.MailMan;
import com.chilkatsoft.chilkat2.PrivateKey;

public class ChilkatExample {

    public static void main(String[] args) {
        // This example requires the Chilkat API to have been previously unlocked.
        // See Global Unlock Sample for sample code.

        MailMan mailman = new MailMan();
        Dkim dkim = new Dkim();

        // SMTP server settings...
        mailman.setSmtpHost("SMTP_DOMAIN");
        mailman.setSmtpUsername("SMTP_LOGIN");
        mailman.setSmtpPassword("SMTP_PASSWORD");
        mailman.setSmtpPort(465);
        mailman.setSmtpSsl(true);

        Email email = new Email();

        email.setSubject("This is a test");
        email.setBody("This is a test");
        email.setFrom("Chilkat Support <support@chilkatsoft.com>");

        // Add some recipients (BCC recipients are added below)
        email.addTo("Chilkat Software", "chilkat_software@yahoo.com");
        email.addTo("Chilkat Admin", "admin@chilkatsoft.com");
        email.addCC("Chilkat Admin", "admin@chilkat.io");

        // When sending an email with a DKIM signature, the MIME
        // of the email must not be modified prior to
        // or during the sending process.  Therefore, the MIME of the
        // email is assembled, the DKIM signature is added, and then
        // SendMimeBd is called to send the email.

        // First get the MIME of the email.  Calling RenderToMimeBd
        // causes the email to be signed and/or encrypted if those options
        // have been selected.  The MIME returned by RenderToMimeBd
        // is the exact MIME that would've been sent if SendEmail was
        // called.  We'll add a DKIM signature header to this MIME and then send...
        BinData bdMime = new BinData();
        try {
            mailman.renderToMimeBd(email, bdMime);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // To create a DKIM signature,
        // you'll need to provide the following:
        // (1) An RSA private key in any common file format.
        // (2) The domain name (typically the same domain
        // as the sender of an email).
        // (3) A selector for the domain name -- an arbitrary string
        // to identify the matching public key in DNS.

        // To allow an email recipient to verify the DKIM signature via an
        // external email client supporting DKIM or using other software,
        // you will need to create a DNS record with the selector
        // and matching public key.  This example does not provide
        // information about DKIM DNS record creation.
        // (Chilkat does not provide an API for creating DNS records.
        // Creating the DKIM DNS record is something you would do
        // manually.)

        // Set the domain and selector:
        // You'll need to provide your own values here..
        dkim.setDkimDomain("chilkatsoft.com");
        dkim.setDkimSelector("brisbane");

        // Load a private key from any common RSA private key
        // format, such as DER, PKCS8, PEM, XML, etc.
        // The LoadDkimPkFile method automatically detects
        // the file format and reads it appropriately.
        // If a password is not required, you'll still need to provide
        // an empty password string argument, but it is ignored.
        String password = "passwd";
        PrivateKey privKey = new PrivateKey();
        try {
            privKey.loadAnyFormatFile("qa_data/pem/rsa_passwd.pem", password);

            dkim.setDkimPrivateKey(privKey);

            // Add the DKIM-Signature header to the MIME in bdMime
            dkim.dkimSign(bdMime);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // If desired, examine the MIME of the email being sent.
        bdMime.writeFile("qa_output/dkimSigned.eml");

        // ---- Prepare to send the email contained in bdMime ---

        // To send to multiple email addresses, the strRecipients should be set to a comma-separated
        // list of email addresses.

        // Note: This is where we can add additional BCC addreses.
        // Here we are adding "chilkat.support@gmail.com" as an additional BCC address.
        // Notice that the 1st three email addresses are NOT BCC because these email addresses
        // appear in the MIME header of the email (in the "To" and "CC" header fields).
        // A BCC email address does not appear in the MIME, and thus the non-BCC recipients cannot see
        // that the email was also sent to the BCC address.  (BCC means "blind carbon copy")
        String strRecipients = "chilkat_software@yahoo.com, admin@chilkatsoft.com, admin@chilkat.io, chilkat.support@gmail.com";
        String strFrom = "support@chilkatsoft.com";

        try {
            mailman.sendMimeBd(strFrom, strRecipients, bdMime);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        try {
            mailman.closeSmtpConnection();
        } catch (ChilkatException e) {
            System.out.println("Connection to SMTP server not closed cleanly.");
        }

        System.out.println("DKIM Signed Mail Sent!");
    }
}