mirror of https://github.com/zulip/zulip.git
310 lines
10 KiB
Python
Executable File
310 lines
10 KiB
Python
Executable File
#!/usr/bin/python
|
|
|
|
"""
|
|
Forward messages sent to the configured email gateway to Zulip.
|
|
|
|
Messages to that address go to the Inbox of emailgateway@zulip.com.
|
|
|
|
Messages meant for Zulip have a special recipient form of
|
|
|
|
<stream name>+<regenerable stream token>@streams.zulip.com
|
|
|
|
We extract and validate the target stream from information in the
|
|
recipient address and retrieve, forward, and archive the message.
|
|
|
|
Run this management command out of a cron job.
|
|
"""
|
|
|
|
import email
|
|
from os import path
|
|
from email.header import decode_header
|
|
import logging
|
|
import re
|
|
import sys
|
|
|
|
from django.conf import settings
|
|
from django.core.management.base import BaseCommand
|
|
|
|
from zerver.lib.actions import decode_email_address
|
|
from zerver.lib.upload import upload_message_image
|
|
from zerver.models import Stream, get_user_profile_by_email
|
|
|
|
from twisted.internet import protocol, reactor, ssl
|
|
from twisted.mail import imap4
|
|
|
|
import html2text
|
|
|
|
sys.path.insert(0, path.join(path.dirname(__file__), "../../../api"))
|
|
import zulip
|
|
|
|
## Setup ##
|
|
|
|
log_format = "%(asctime)s: %(message)s"
|
|
logging.basicConfig(format=log_format)
|
|
|
|
formatter = logging.Formatter(log_format)
|
|
file_handler = logging.FileHandler(settings.EMAIL_LOG_PATH)
|
|
file_handler.setFormatter(formatter)
|
|
|
|
logger = logging.getLogger(__name__)
|
|
logger.setLevel(logging.DEBUG)
|
|
logger.addHandler(file_handler)
|
|
|
|
email_gateway_user = get_user_profile_by_email(settings.EMAIL_GATEWAY_BOT_ZULIP_USER)
|
|
api_key = email_gateway_user.api_key
|
|
|
|
if settings.DEPLOYED:
|
|
staging_api_client = zulip.Client(
|
|
site="https://staging.zulip.com",
|
|
email=settings.EMAIL_GATEWAY_BOT_ZULIP_USER,
|
|
api_key=api_key)
|
|
|
|
|
|
api_client = zulip.Client(
|
|
site=settings.EXTERNAL_HOST,
|
|
email=settings.EMAIL_GATEWAY_BOT_ZULIP_USER,
|
|
api_key=api_key)
|
|
else:
|
|
api_client = staging_api_client = zulip.Client(
|
|
site=settings.EXTERNAL_HOST,
|
|
email=settings.EMAIL_GATEWAY_BOT_ZULIP_USER,
|
|
api_key=api_key)
|
|
|
|
def redact_stream(error_message):
|
|
domain = settings.EMAIL_GATEWAY_PATTERN.rsplit('@')[-1]
|
|
stream_match = re.search(r'\b(.*?)@' + domain, error_message)
|
|
if stream_match:
|
|
stream_name = stream_match.groups()[0]
|
|
return error_message.replace(stream_name, "X" * len(stream_name))
|
|
return error_message
|
|
|
|
def report_to_zulip(error_message):
|
|
error_stream = Stream.objects.get(name="errors", realm__domain=settings.ADMIN_DOMAIN)
|
|
send_zulip(error_stream, "email mirror error",
|
|
"""~~~\n%s\n~~~""" % (error_message,))
|
|
|
|
def log_and_report(email_message, error_message, debug_info):
|
|
scrubbed_error = "Sender: %s\n%s" % (email_message.get("From"),
|
|
redact_stream(error_message))
|
|
|
|
if "to" in debug_info:
|
|
scrubbed_error = "Stream: %s\n%s" % (redact_stream(debug_info["to"]),
|
|
scrubbed_error)
|
|
|
|
if "stream" in debug_info:
|
|
scrubbed_error = "Realm: %s\n%s" % (debug_info["stream"].realm.domain,
|
|
scrubbed_error)
|
|
|
|
logger.error(scrubbed_error)
|
|
report_to_zulip(scrubbed_error)
|
|
|
|
## Sending the Zulip ##
|
|
|
|
class ZulipEmailForwardError(Exception):
|
|
pass
|
|
|
|
def send_zulip(stream, topic, content):
|
|
# TODO: restrictions on who can send? Consider: cross-realm
|
|
# messages, private streams.
|
|
if stream.realm.domain == 'zulip.com':
|
|
client = staging_api_client
|
|
else:
|
|
client = api_client
|
|
|
|
message_data = {
|
|
"type": "stream",
|
|
# TODO: handle rich formatting.
|
|
"content": content[:2000],
|
|
"subject": topic[:60],
|
|
"to": stream.name,
|
|
"domain": stream.realm.domain
|
|
}
|
|
|
|
response = client.send_message(message_data)
|
|
if response["result"] != "success":
|
|
raise ZulipEmailForwardError(response["msg"])
|
|
|
|
def valid_stream(stream_name, token):
|
|
try:
|
|
stream = Stream.objects.get(email_token=token)
|
|
return stream.name.lower() == stream_name.lower()
|
|
except Stream.DoesNotExist:
|
|
return False
|
|
|
|
def get_message_part_by_type(message, content_type):
|
|
charsets = message.get_charsets()
|
|
|
|
for idx, part in enumerate(message.walk()):
|
|
if part.get_content_type() == content_type:
|
|
content = part.get_payload(decode=True)
|
|
if charsets[idx]:
|
|
content = content.decode(charsets[idx], errors="ignore")
|
|
return content
|
|
|
|
def extract_body(message):
|
|
# If the message contains a plaintext version of the body, use
|
|
# that.
|
|
plaintext_content = get_message_part_by_type(message, "text/plain")
|
|
if plaintext_content:
|
|
return plaintext_content
|
|
|
|
# If we only have an HTML version, try to make that look nice.
|
|
html_content = get_message_part_by_type(message, "text/html")
|
|
if html_content:
|
|
converter = html2text.HTML2Text()
|
|
converter.ignore_links = True
|
|
converter.ignore_images = True
|
|
return converter.handle(html_content)
|
|
|
|
raise ZulipEmailForwardError("Unable to find plaintext or HTML message body")
|
|
|
|
def filter_footer(text):
|
|
# Try to filter out obvious footers.
|
|
possible_footers = filter(lambda line: line.strip().startswith("--"),
|
|
text.split("\n"))
|
|
if len(possible_footers) != 1:
|
|
# Be conservative and don't try to scrub content if there
|
|
# isn't a trivial footer structure.
|
|
return text
|
|
|
|
return text.partition("--")[0].strip()
|
|
|
|
def extract_and_upload_attachments(message):
|
|
attachment_links = []
|
|
|
|
payload = message.get_payload()
|
|
if not isinstance(payload, list):
|
|
# This is not a multipart message, so it can't contain attachments.
|
|
return ""
|
|
|
|
for part in payload:
|
|
content_type = part.get_content_type()
|
|
filename = part.get_filename()
|
|
if filename:
|
|
s3_url = upload_message_image(filename, content_type,
|
|
part.get_payload(decode=True),
|
|
email_gateway_user)
|
|
formatted_link = "[%s](%s)" % (filename, s3_url)
|
|
attachment_links.append(formatted_link)
|
|
|
|
return "\n".join(attachment_links)
|
|
|
|
def extract_and_validate(email):
|
|
try:
|
|
stream_name, token = decode_email_address(email)
|
|
except TypeError:
|
|
raise ZulipEmailForwardError("Malformed email recipient " + email)
|
|
|
|
if not valid_stream(stream_name, token):
|
|
raise ZulipEmailForwardError("Bad stream token from email recipient " + email)
|
|
|
|
return Stream.objects.get(email_token=token)
|
|
|
|
## IMAP callbacks ##
|
|
|
|
def logout(result, proto):
|
|
# Log out.
|
|
return proto.logout()
|
|
|
|
def delete(result, proto):
|
|
# Close the connection, which also processes any flags that were
|
|
# set on messages.
|
|
return proto.close().addCallback(logout, proto)
|
|
|
|
def find_emailgateway_recipient(message):
|
|
# We can't use Delivered-To; if there is a X-Gm-Original-To
|
|
# it is more accurate, so try to find the most-accurate
|
|
# recipient list in descending priority order
|
|
recipient_headers = ["X-Gm-Original-To", "Delivered-To", "To"]
|
|
recipients = []
|
|
for recipient_header in recipient_headers:
|
|
r = message.get_all(recipient_header, None)
|
|
if r:
|
|
recipients = r
|
|
break
|
|
|
|
pattern_parts = [re.escape(part) for part in settings.EMAIL_GATEWAY_PATTERN.split('%s')]
|
|
match_email_re = re.compile(".*?".join(pattern_parts))
|
|
for recipient_email in recipients:
|
|
if match_email_re.match(recipient_email):
|
|
return recipient_email
|
|
|
|
raise ZulipEmailForwardError("Missing recipient in mirror email")
|
|
|
|
def fetch(result, proto, mailboxes):
|
|
if not result:
|
|
return proto.logout()
|
|
|
|
message_uids = result.keys()
|
|
# Make sure we forward the messages in time-order.
|
|
message_uids.sort()
|
|
for uid in message_uids:
|
|
message = email.message_from_string(result[uid]["RFC822"])
|
|
subject = decode_header(message.get("Subject", "(no subject)"))[0][0]
|
|
|
|
debug_info = {}
|
|
|
|
try:
|
|
body = filter_footer(extract_body(message))
|
|
to = find_emailgateway_recipient(message)
|
|
debug_info["to"] = to
|
|
stream = extract_and_validate(to)
|
|
debug_info["stream"] = stream
|
|
body += extract_and_upload_attachments(message)
|
|
if not body:
|
|
# You can't send empty Zulips, so to avoid confusion over the
|
|
# email forwarding failing, set a dummy message body.
|
|
body = "(No email body)"
|
|
send_zulip(stream, subject, body)
|
|
except ZulipEmailForwardError, e:
|
|
# TODO: notify sender of error, retry if appropriate.
|
|
log_and_report(message, e.message, debug_info)
|
|
|
|
# Delete the processed messages from the Inbox.
|
|
message_set = ",".join([result[key]["UID"] for key in message_uids])
|
|
d = proto.addFlags(message_set, ["\\Deleted"], uid=True, silent=False)
|
|
d.addCallback(delete, proto)
|
|
|
|
return d
|
|
|
|
def examine_mailbox(result, proto, mailbox):
|
|
# Fetch messages from a particular mailbox.
|
|
return proto.fetchMessage("1:*", uid=True).addCallback(fetch, proto, mailbox)
|
|
|
|
def select_mailbox(result, proto):
|
|
# Select which mailbox we care about.
|
|
mbox = filter(lambda x: settings.EMAIL_GATEWAY_IMAP_FOLDER in x[2], result)[0][2]
|
|
return proto.select(mbox).addCallback(examine_mailbox, proto, result)
|
|
|
|
def list_mailboxes(res, proto):
|
|
# List all of the mailboxes for this account.
|
|
return proto.list("","*").addCallback(select_mailbox, proto)
|
|
|
|
def connected(proto):
|
|
d = proto.login(settings.EMAIL_GATEWAY_LOGIN, settings.EMAIL_GATEWAY_PASSWORD)
|
|
d.addCallback(list_mailboxes, proto)
|
|
d.addErrback(login_failed)
|
|
return d
|
|
|
|
def login_failed(failure):
|
|
return failure
|
|
|
|
def done(_):
|
|
reactor.callLater(0, reactor.stop)
|
|
|
|
def main():
|
|
imap_client = protocol.ClientCreator(reactor, imap4.IMAP4Client)
|
|
d = imap_client.connectSSL(settings.EMAIL_GATEWAY_IMAP_SERVER, settings.EMAIL_GATEWAY_IMAP_PORT, ssl.ClientContextFactory())
|
|
d.addCallbacks(connected, login_failed)
|
|
d.addBoth(done)
|
|
|
|
class Command(BaseCommand):
|
|
help = """Forward emails sent to the configured email gateway to Zulip.
|
|
|
|
Run this command out of a cron job.
|
|
"""
|
|
|
|
def handle(self, **options):
|
|
reactor.callLater(0, main)
|
|
reactor.run()
|