# File transport :: Lettre site
Documentation for the Lettre mailer in Rust
Author: Alexis Mousset

Edit this page

# File transport

The file transport writes the emails to the given directory. The name of the file will be `message_id.txt`. It can be useful for testing purposes, or if you want to keep track of sent messages.

    extern crate lettre;

    use std::env::temp_dir;

    use lettre::file::FileEmailTransport;
    use lettre::{SimpleSendableEmail, EmailTransport};

    fn main() {
        // Write to the local temp directory
        let mut sender = FileEmailTransport::new(temp_dir());
        let email = SimpleSendableEmail::new(
                        "user@localhost".to_string(),
                        &["root@localhost".to_string()],
                        "message_id".to_string(),
                        "Hello world".to_string(),
                    ).unwrap();

        let result = sender.send(&email);
        assert!(result.is_ok());
    }

Example result in `/tmp/b7c211bc-9811-45ce-8cd9-68eab575d695.txt`:

    b7c211bc-9811-45ce-8cd9-68eab575d695: from=<user@localhost> to=<root@localhost>
    To: <root@localhost>
    From: <user@localhost>
    Subject: Hello
    Date: Sat, 31 Oct 2015 13:42:19 +0100
    Message-ID: <b7c211bc-9811-45ce-8cd9-68eab575d695.lettre@localhost>

    Hello World!