coins-demo/todo/mail/consumers/tracker.py
Scot Hacker f6d79879ae
Fix MySQL migration (#57)
* Use CharField, not TextField for MySQL compat.

* black formatting
2019-03-25 07:43:53 -07:00

151 lines
5 KiB
Python

import re
import logging
from email.charset import Charset as EMailCharset
from django.db import transaction
from django.db.models import Count
from html2text import html2text
from todo.models import Comment, Task, TaskList
logger = logging.getLogger(__name__)
def part_decode(message):
charset = ("ascii", "ignore")
email_charset = message.get_content_charset()
if email_charset:
charset = (EMailCharset(email_charset).input_charset,)
body = message.get_payload(decode=True)
return body.decode(*charset)
def message_find_mime(message, mime_type):
for submessage in message.walk():
if submessage.get_content_type() == mime_type:
return submessage
return None
def message_text(message):
text_part = message_find_mime(message, "text/plain")
if text_part is not None:
return part_decode(text_part)
html_part = message_find_mime(message, "text/html")
if html_part is not None:
return html2text(part_decode(html_part))
# TODO: find something smart to do when no text if found
return ""
def format_task_title(format_string, message):
return format_string.format(subject=message["subject"], author=message["from"])
DJANGO_TODO_THREAD = re.compile(r"<thread-(\d+)@django-todo>")
def parse_references(task_list, references):
related_messages = []
answer_thread = None
for related_message in references.split():
logger.info("checking reference: %r", related_message)
match = re.match(DJANGO_TODO_THREAD, related_message)
if match is None:
related_messages.append(related_message)
continue
thread_id = int(match.group(1))
new_answer_thread = Task.objects.filter(task_list=task_list, pk=thread_id).first()
if new_answer_thread is not None:
answer_thread = new_answer_thread
if answer_thread is None:
logger.info("no answer thread found in references")
else:
logger.info("found an answer thread: %d", answer_thread)
return related_messages, answer_thread
def insert_message(task_list, message, priority, task_title_format):
if "message-id" not in message:
logger.warning("missing message id, ignoring message")
return
if "from" not in message:
logger.warning('missing "From" header, ignoring message')
return
if "subject" not in message:
logger.warning('missing "Subject" header, ignoring message')
return
logger.info(
"received message:\t"
f"[Subject: {message['subject']}]\t"
f"[Message-ID: {message['message-id']}]\t"
f"[References: {message['references']}]\t"
f"[To: {message['to']}]\t"
f"[From: {message['from']}]"
)
# Due to limitations in MySQL wrt unique_together and TextField (grrr),
# we must use a CharField rather than TextField for message_id.
# In the unlikeley event that we get a VERY long inbound
# message_id, truncate it to the max_length of a MySQL CharField.
original_message_id = message["message-id"]
message_id = (
(original_message_id[:252] + "...")
if len(original_message_id) > 255
else original_message_id
)
message_from = message["from"]
text = message_text(message)
related_messages, answer_thread = parse_references(task_list, message.get("references", ""))
# find the most relevant task to add a comment on.
# among tasks in the selected task list, find the task having the
# most email comments the current message references
best_task = (
Task.objects.filter(task_list=task_list, comment__email_message_id__in=related_messages)
.annotate(num_comments=Count("comment"))
.order_by("-num_comments")
.only("id")
.first()
)
# if no related comment is found but a thread message-id
# (generated by django-todo) could be found, use it
if best_task is None and answer_thread is not None:
best_task = answer_thread
with transaction.atomic():
if best_task is None:
best_task = Task.objects.create(
priority=priority,
title=format_task_title(task_title_format, message),
task_list=task_list,
)
logger.info("using task: %r", best_task)
comment, comment_created = Comment.objects.get_or_create(
task=best_task,
email_message_id=message_id,
defaults={"email_from": message_from, "body": text},
)
logger.info("created comment: %r", comment)
def tracker_consumer(
producer, group=None, task_list_slug=None, priority=1, task_title_format="[MAIL] {subject}"
):
task_list = TaskList.objects.get(group__name=group, slug=task_list_slug)
for message in producer:
try:
insert_message(task_list, message, priority, task_title_format)
except Exception:
# ignore exceptions during insertion, in order to avoid
logger.exception("got exception while inserting message")