Rust

Auto-Generate or Explicitly Specify the Message-ID Email Header

Demonstrates how to auto-generate or explicitly specify the Message-ID header field. Rust

let email = chilkat::Email::new();

email.set_subject("test");
email.set_body("test");
let _ = email.add_to("Joe", "joe@example1.com");
email.set_from("mary@example2.com");

let mailman = chilkat::MailMan::new();

// When the mailman sends email, it renders the email to be sent,
// and then sends the rendered MIME.

// Instead of actually sending the email, this example will render
// to MIME so we can see what would be sent..

// We can explicitly set the Message-ID like this:
mailman.set_auto_gen_message_id(false);
email.add_header_field("Message-ID", "<xyz123@abc>");

let mut mime_str = mailman.render_to_mime(&email).unwrap_or_default();
println!("{}", mime_str);

// This is what we get:

// MIME-Version: 1.0
// Date: Mon, 20 Jul 2020 17:20:09 -0500
// Message-ID: <xyz123@abc>
// Content-Type: text/plain; charset=us-ascii; format=flowed
// Content-Transfer-Encoding: 7bit
// X-Priority: 3 (Normal)
// Subject: test
// To: Joe <joe@example1.com>
// From: mary@example2.com
// 
// test

println!("--------");

// If we auto-generate...
mailman.set_auto_gen_message_id(true);
mime_str = mailman.render_to_mime(&email).unwrap_or_default();
println!("{}", mime_str);

// We get this:

// MIME-Version: 1.0
// Date: Mon, 20 Jul 2020 17:21:20 -0500
// Message-ID: <04EDE096BBFE484967F6398A973B0FCF6EA09A44@CHILKATSLICE>
// Content-Type: text/plain; charset=us-ascii; format=flowed
// Content-Transfer-Encoding: 7bit
// X-Priority: 3 (Normal)
// Subject: test
// To: Joe <joe@example1.com>
// From: mary@example2.com
// 
// test