"""
Mail sending helpers
See documentation in docs/topics/email.rst
"""
from __future__ import annotations
import logging
import warnings
from email import encoders as Encoders
from email.mime.base import MIMEBase
from email.mime.multipart import MIMEMultipart
from email.mime.nonmultipart import MIMENonMultipart
from email.mime.text import MIMEText
from email.utils import formatdate
from io import BytesIO
from typing import IO, TYPE_CHECKING, Any
from twisted.internet import ssl
from twisted.internet.defer import Deferred
from scrapy.exceptions import ScrapyDeprecationWarning
from scrapy.utils.misc import arg_to_iter
from scrapy.utils.python import to_bytes
if TYPE_CHECKING:
from collections.abc import Callable, Sequence
# imports twisted.internet.reactor
from twisted.mail.smtp import ESMTPSenderFactory
from twisted.python.failure import Failure
# typing.Self requires Python 3.11
from typing_extensions import Self
from scrapy.crawler import Crawler
from scrapy.settings import BaseSettings
logger = logging.getLogger(__name__)
# Defined in the email.utils module, but undocumented:
# https://github.com/python/cpython/blob/v3.9.0/Lib/email/utils.py#L42
COMMASPACE = ", "
def _to_bytes_or_none(text: str | bytes | None) -> bytes | None:
if text is None:
return None
return to_bytes(text)
[docs]class MailSender:
def __init__(
self,
smtphost: str = "localhost",
mailfrom: str = "scrapy@localhost",
smtpuser: str | None = None,
smtppass: str | None = None,
smtpport: int = 25,
smtptls: bool = False,
smtpssl: bool = False,
debug: bool = False,
):
self.smtphost: str = smtphost
self.smtpport: int = smtpport
self.smtpuser: bytes | None = _to_bytes_or_none(smtpuser)
self.smtppass: bytes | None = _to_bytes_or_none(smtppass)
self.smtptls: bool = smtptls
self.smtpssl: bool = smtpssl
self.mailfrom: str = mailfrom
self.debug: bool = debug
@classmethod
def from_settings(cls, settings: BaseSettings) -> Self:
warnings.warn(
f"{cls.__name__}.from_settings() is deprecated, use from_crawler() instead.",
category=ScrapyDeprecationWarning,
stacklevel=2,
)
return cls._from_settings(settings)
[docs] @classmethod
def from_crawler(cls, crawler: Crawler) -> Self:
return cls._from_settings(crawler.settings)
@classmethod
def _from_settings(cls, settings: BaseSettings) -> Self:
return cls(
smtphost=settings["MAIL_HOST"],
mailfrom=settings["MAIL_FROM"],
smtpuser=settings["MAIL_USER"],
smtppass=settings["MAIL_PASS"],
smtpport=settings.getint("MAIL_PORT"),
smtptls=settings.getbool("MAIL_TLS"),
smtpssl=settings.getbool("MAIL_SSL"),
)
[docs] def send(
self,
to: str | list[str],
subject: str,
body: str,
cc: str | list[str] | None = None,
attachs: Sequence[tuple[str, str, IO[Any]]] = (),
mimetype: str = "text/plain",
charset: str | None = None,
_callback: Callable[..., None] | None = None,
) -> Deferred[None] | None:
from twisted.internet import reactor
msg: MIMEBase
if attachs:
msg = MIMEMultipart()
else:
msg = MIMENonMultipart(*mimetype.split("/", 1))
to = list(arg_to_iter(to))
cc = list(arg_to_iter(cc))
msg["From"] = self.mailfrom
msg["To"] = COMMASPACE.join(to)
msg["Date"] = formatdate(localtime=True)
msg["Subject"] = subject
rcpts = to[:]
if cc:
rcpts.extend(cc)
msg["Cc"] = COMMASPACE.join(cc)
if attachs:
if charset:
msg.set_charset(charset)
msg.attach(MIMEText(body, "plain", charset or "us-ascii"))
for attach_name, attach_mimetype, f in attachs:
part = MIMEBase(*attach_mimetype.split("/"))
part.set_payload(f.read())
Encoders.encode_base64(part)
part.add_header(
"Content-Disposition", "attachment", filename=attach_name
)
msg.attach(part)
else:
msg.set_payload(body, charset)
if _callback:
_callback(to=to, subject=subject, body=body, cc=cc, attach=attachs, msg=msg)
if self.debug:
logger.debug(
"Debug mail sent OK: To=%(mailto)s Cc=%(mailcc)s "
'Subject="%(mailsubject)s" Attachs=%(mailattachs)d',
{
"mailto": to,
"mailcc": cc,
"mailsubject": subject,
"mailattachs": len(attachs),
},
)
return None
dfd: Deferred[Any] = self._sendmail(
rcpts, msg.as_string().encode(charset or "utf-8")
)
dfd.addCallback(self._sent_ok, to, cc, subject, len(attachs))
dfd.addErrback(self._sent_failed, to, cc, subject, len(attachs))
reactor.addSystemEventTrigger("before", "shutdown", lambda: dfd)
return dfd
def _sent_ok(
self, result: Any, to: list[str], cc: list[str], subject: str, nattachs: int
) -> None:
logger.info(
"Mail sent OK: To=%(mailto)s Cc=%(mailcc)s "
'Subject="%(mailsubject)s" Attachs=%(mailattachs)d',
{
"mailto": to,
"mailcc": cc,
"mailsubject": subject,
"mailattachs": nattachs,
},
)
def _sent_failed(
self,
failure: Failure,
to: list[str],
cc: list[str],
subject: str,
nattachs: int,
) -> Failure:
errstr = str(failure.value)
logger.error(
"Unable to send mail: To=%(mailto)s Cc=%(mailcc)s "
'Subject="%(mailsubject)s" Attachs=%(mailattachs)d'
"- %(mailerr)s",
{
"mailto": to,
"mailcc": cc,
"mailsubject": subject,
"mailattachs": nattachs,
"mailerr": errstr,
},
)
return failure
def _sendmail(self, to_addrs: list[str], msg: bytes) -> Deferred[Any]:
from twisted.internet import reactor
msg_io = BytesIO(msg)
d: Deferred[Any] = Deferred()
factory = self._create_sender_factory(to_addrs, msg_io, d)
if self.smtpssl:
reactor.connectSSL(
self.smtphost, self.smtpport, factory, ssl.ClientContextFactory()
)
else:
reactor.connectTCP(self.smtphost, self.smtpport, factory)
return d
def _create_sender_factory(
self, to_addrs: list[str], msg: IO[bytes], d: Deferred[Any]
) -> ESMTPSenderFactory:
from twisted.mail.smtp import ESMTPSenderFactory
factory_keywords: dict[str, Any] = {
"heloFallback": True,
"requireAuthentication": False,
"requireTransportSecurity": self.smtptls,
"hostname": self.smtphost,
}
factory = ESMTPSenderFactory(
self.smtpuser,
self.smtppass,
self.mailfrom,
to_addrs,
msg,
d,
**factory_keywords,
)
factory.noisy = False
return factory