/usr/lib/python3/dist-packages/twisted/mail
Edit: /usr/lib/python3/dist-packages/twisted/mail/bounce.py (3170B)
# -*- test-case-name: twisted.mail.test.test_bounce -*-
#
# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.
"""
Support for bounce message generation.
"""
import email.utils
import os
import time
from io import SEEK_END, SEEK_SET, StringIO
from twisted.mail import smtp
BOUNCE_FORMAT = """\
From: postmaster@{failedDomain}
To: {failedFrom}
Subject: Returned Mail: see transcript for details
Message-ID: {messageID}
Content-Type: multipart/report; report-type=delivery-status;
boundary="{boundary}"
--{boundary}
{transcript}
--{boundary}
Content-Type: message/delivery-status
Arrival-Date: {ctime}
Final-Recipient: RFC822; {failedTo}
"""
def generateBounce(message, failedFrom, failedTo, transcript="", encoding="utf-8"):
"""
Generate a bounce message for an undeliverable email message.
@type message: a file-like object
@param message: The undeliverable message.
@type failedFrom: L{bytes} or L{unicode}
@param failedFrom: The originator of the undeliverable message.
@type failedTo: L{bytes} or L{unicode}
@param failedTo: The destination of the undeliverable message.
@type transcript: L{bytes} or L{unicode}
@param transcript: An error message to include in the bounce message.
@type encoding: L{str} or L{unicode}
@param encoding: Encoding to use, default: utf-8
@rtype: 3-L{tuple} of (E{1}) L{bytes}, (E{2}) L{bytes}, (E{3}) L{bytes}
@return: The originator, the destination and the contents of the bounce
message. The destination of the bounce message is the originator of
the undeliverable message.
"""
if isinstance(failedFrom, bytes):
failedFrom = failedFrom.decode(encoding)
if isinstance(failedTo, bytes):
failedTo = failedTo.decode(encoding)
if not transcript:
transcript = """\
I'm sorry, the following address has permanent errors: {failedTo}.
I've given up, and I will not retry the message again.
""".format(
failedTo=failedTo
)
failedAddress = email.utils.parseaddr(failedTo)[1]
data = {
"boundary": "{}_{}_{}".format(time.time(), os.getpid(), "XXXXX"),
"ctime": time.ctime(time.time()),
"failedAddress": failedAddress,
"failedDomain": failedAddress.split("@", 1)[1],
"failedFrom": failedFrom,
"failedTo": failedTo,
"messageID": smtp.messageid(uniq="bounce"),
"message": message,
"transcript": transcript,
}
fp = StringIO()
fp.write(BOUNCE_FORMAT.format(**data))
orig = message.tell()
message.seek(0, SEEK_END)
sz = message.tell()
message.seek(orig, SEEK_SET)
if sz > 10000:
while 1:
line = message.readline()
if isinstance(line, bytes):
line = line.decode(encoding)
if len(line) <= 0:
break
fp.write(line)
else:
messageContent = message.read()
if isinstance(messageContent, bytes):
messageContent = messageContent.decode(encoding)
fp.write(messageContent)
return b"", failedFrom.encode(encoding), fp.getvalue().encode(encoding)