v/vlib/net/smtp/smtp.v

190 lines
4.1 KiB
V

module smtp
/*
*
* smtp module
* Created by: nedimf (07/2020)
*/
import net
import encoding.base64
import strings
import time
const (
recv_size = 128
)
enum ReplyCode {
ready = 220
close = 221
auth_ok = 235
action_ok = 250
mail_start = 354
}
pub enum BodyType {
text
html
}
pub struct Client {
mut:
socket net.Socket
pub:
server string
port int = 25
username string
password string
from string
pub mut:
is_open bool
}
pub struct Mail {
from string
to string
cc string
bcc string
date time.Time = time.now()
subject string
body_type BodyType
body string
}
// new_client returns a new SMTP client and connects to it
pub fn new_client(config Client) ?Client {
mut c := config
c.reconnect()?
return c
}
// reconnect reconnects to the SMTP server if the connection was closed
pub fn (mut c Client) reconnect() ? {
if c.is_open { return error('Already connected to server') }
socket := net.dial(c.server, c.port) or { return error('Connecting to server failed') }
c.socket = socket
c.expect_reply(.ready) or { return error('Received invalid response from server') }
c.send_ehlo() or { return error('Sending EHLO packet failed') }
c.send_auth() or { return error('Authenticating to server failed') }
c.is_open = true
}
// send sends an email
pub fn (c Client) send(config Mail) ? {
if !c.is_open { return error('Disconnected from server') }
from := if config.from != '' { config.from } else { c.from }
c.send_mailfrom(from) or { return error('Sending mailfrom failed') }
c.send_mailto(config.to) or { return error('Sending mailto failed') }
c.send_data() or { return error('Sending mail data failed') }
c.send_body({ config | from: from }) or { return error('Sending mail body failed') }
}
// quit closes the connection to the server
pub fn (mut c Client) quit() ? {
c.send_str('QUIT\r\n')
c.expect_reply(.close)
c.socket.close()?
c.is_open = false
}
// expect_reply checks if the SMTP server replied with the expected reply code
fn (c Client) expect_reply(expected ReplyCode) ? {
bytes, len := c.socket.recv(recv_size)
str := tos(bytes, len).trim_space()
$if smtp_debug? {
eprintln('\n\n[RECV START]')
eprint(str)
}
// Read remaining data in the socket
if len >= recv_size {
for {
tbytes, tlen := c.socket.recv(recv_size)
str2 := tos(tbytes, tlen)
$if smtp_debug? { eprint(str2) }
if tlen < recv_size { break }
}
}
$if smtp_debug? {
eprintln('\n[RECV END]')
}
if len >= 3 {
status := str[..3].int()
if status != expected {
return error('Received unexpected status code $status, expecting $expected')
}
} else { return error('Recieved unexpected SMTP data: $str') }
}
[inline]
fn (c Client) send_str(s string) ? {
$if smtp_debug? {
eprintln('\n\n[SEND START]')
eprint(s.trim_space())
eprintln('\n[SEND END]')
}
c.socket.send_string(s)?
}
[inline]
fn (c Client) send_ehlo() ? {
c.send_str('EHLO $c.server\r\n')?
c.expect_reply(.action_ok)?
}
[inline]
fn (c Client) send_auth() ? {
if c.username.len == 0 {
return
}
mut sb := strings.new_builder(100)
sb.write_b(0)
sb.write(c.username)
sb.write_b(0)
sb.write(c.password)
a := sb.str()
auth := 'AUTH PLAIN ${base64.encode(a)}\r\n'
c.send_str(auth)?
c.expect_reply(.auth_ok)?
}
fn (c Client) send_mailfrom(from string) ? {
c.send_str('MAIL FROM: <$from>\r\n')?
c.expect_reply(.action_ok)?
}
fn (c Client) send_mailto(to string) ? {
c.send_str('RCPT TO: <$to>\r\n')?
c.expect_reply(.action_ok)?
}
fn (c Client) send_data() ? {
c.send_str('DATA\r\n')?
c.expect_reply(.mail_start)
}
fn (c Client) send_body(cfg Mail) ? {
is_html := cfg.body_type == .html
date := cfg.date.utc_string().trim_right(' UTC') // TODO
mut sb := strings.new_builder(200)
sb.write('From: $cfg.from\r\n')
sb.write('To: <$cfg.to>\r\n')
sb.write('Cc: <$cfg.cc>\r\n')
sb.write('Bcc: <$cfg.bcc>\r\n')
sb.write('Date: $date\r\n')
sb.write('Subject: $cfg.subject\r\n')
if is_html {
sb.write('Content-Type: text/html; charset=ISO-8859-1')
}
sb.write('\r\n\r\n')
sb.write(cfg.body)
sb.write('\r\n.\r\n')
c.send_str(sb.str())?
c.expect_reply(.action_ok)?
}