smtp.md

SMTP Library (smtp)

Overview

libsmtp provides a practical SMTP client/server subset built on socket.

This library currently works on Magnolia's native runtime. In the JavaScript runtime it will fail with structured socket :error results until stream socket support is added there.

Supported commands in this implementation:

• Client: EHLO, HELO, STARTTLS, MAIL FROM, RCPT TO, DATA, QUIT
• Server: EHLO, HELO, NOOP, RSET, STARTTLS, MAIL FROM, RCPT TO, DATA, QUIT

Import

smtp := import('smtp')

Client API

connect(address, options?)

Returns:

{ type: :ok, greeting: {...}, client: {...} }

Client methods:

• command(line)
• ehlo(name?)
• helo(name?)
• startTLS(options?)
• mail(from)
• rcpt(to)
• data(body)
• send({from, to, raw? , headers?, body?})
• quit()
• close()

Server API

listen(address, handlers?, options?)

Starts an SMTP server and returns a close function.

Handler fields:

• hostname server banner name
• onMessage(message) called after DATA

Message shape:

{
    from: 'sender@example.com'
    to: ['rcpt@example.com']
    body: 'raw message body including headers'
    tls?: false
}

onMessage should return an object like:

{ ok?: true, code: 250, message: 'queued' }

STARTTLS

Enable STARTTLS with listener options:

{
    startTLS?: true
    certFile: './cert.pem'
    keyFile: './key.pem'
}

Example

smtp := import('smtp')
{ wait: wait } := import('std')

closeServer := smtp.listen('127.0.0.1:2525', {
    onMessage: fn(message) {
        println(message.body)
        { ok?: true, message: 'queued' }
    }
})

wait(0.05)
clientResult := smtp.connect('127.0.0.1:2525')
client := clientResult.client
client.ehlo('localhost')
client.send({
    from: 'sender@example.com'
    to: ['rcpt@example.com']
    raw: 'Subject: Demo\r\n\r\nhello smtp'
})
client.quit()
closeServer()