Wrong encoding / chars in email via lettre

Question

I'm sending email from a rust program.
Email text is in a Postgresql database with encoding UTF8. I query database via postgres crate: https://crates.io/crates/postgres

I'm working on Windows. If I print the message seems correct:

But when I receive it on Thunderbird it display: "Questo =C3=A8 il"

If I read it from Gmail web interface it seems correct, but when I check "Show original message", it is wrong again.

I read messages with a query like this:

let query = "SELECT * FROM myschema.retrieve_messages($1, $2, $3, $4);";
for row in &db_client.query(query, &[&pg_working_date, &max_messages_per_run, &_force_retry, &run_id]).unwrap()

Then I loop on results, and put them in a Vec. I retrieve body with:

mail_body: row.get("mail_body")

If I print body of message with:

println!("Body is: {}", m.mail_body);

It seems ok.

Then I use lettre crate to send email https://crates.io/crates/lettre
I connect like this:

    let mailer = SmtpTransport::relay(&smtp_server)
    .unwrap()
    .credentials(smpt_credentials)
    .build();

And I ship message with this code:

        let shipping_message = Message::builder()
        .from("Hello <shippingaddress@shippngdomain.something>".parse().unwrap())
        .to(m.email_address.parse().unwrap())
        .subject(m.mail_subject)
        .body(m.mail_body)
        .unwrap();

And then the shipment:

match mailer.send(&shipping_message) {some other irrelevant code}

There is something wrong in code? What can I check?

Answer 1

When you call MessageBuilder::body your body is encoded:

Automatically gets encoded with 7bit, quoted-printable or base64 Content-Transfer-Encoding, based on the most efficient and valid encoding for body.

If this behaviour is not desirable, you can use a MIME body with SinglePart instead.

I think this should do the trick for you:

        let shipping_message = Message::builder()
        .from("Hello <shippingaddress@shippngdomain.something>".parse().unwrap())
        .to(m.email_address.parse().unwrap())
        .subject(m.mail_subject)
        .singlepart(SinglePart::plain(m.mail_body)) // plain UTF-8 encoding
        .unwrap();