django-helpdesk/helpdesk/templated_email.py
Timothy Hobbs 6c37d73d4e
DRY out email sending code and normalize behavior
This refactor removes duplicated logic for deciding whom the messages get sent to.
It also normalizes behavior ensuring that all CCed addresses are sent to in all cases that CCed individuals should be notified.
2018-11-01 14:56:17 +01:00

115 lines
4.2 KiB
Python

import os
import mimetypes
import logging
from smtplib import SMTPException
from django.utils.safestring import mark_safe
logger = logging.getLogger('helpdesk')
def send_templated_mail(template_name,
context,
recipients,
sender=None,
bcc=None,
fail_silently=False,
files=None):
"""
send_templated_mail() is a wrapper around Django's e-mail routines that
allows us to easily send multipart (text/plain & text/html) e-mails using
templates that are stored in the database. This lets the admin provide
both a text and a HTML template for each message.
template_name is the slug of the template to use for this message (see
models.EmailTemplate)
context is a dictionary to be used when rendering the template
recipients can be either a string, eg 'a@b.com', or a list of strings.
sender should contain a string, eg 'My Site <me@z.com>'. If you leave it
blank, it'll use settings.DEFAULT_FROM_EMAIL as a fallback.
bcc is an optional list of addresses that will receive this message as a
blind carbon copy.
fail_silently is passed to Django's mail routine. Set to 'True' to ignore
any errors at send time.
files can be a list of tuples. Each tuple should be a filename to attach,
along with the File objects to be read. files can be blank.
"""
from django.core.mail import EmailMultiAlternatives
from django.template import engines
from_string = engines['django'].from_string
from helpdesk.models import EmailTemplate
from helpdesk.settings import HELPDESK_EMAIL_SUBJECT_TEMPLATE, \
HELPDESK_EMAIL_FALLBACK_LOCALE
locale = context['queue'].get('locale') or HELPDESK_EMAIL_FALLBACK_LOCALE
try:
t = EmailTemplate.objects.get(template_name__iexact=template_name, locale=locale)
except EmailTemplate.DoesNotExist:
try:
t = EmailTemplate.objects.get(template_name__iexact=template_name, locale__isnull=True)
except EmailTemplate.DoesNotExist:
logger.warning('template "%s" does not exist, no mail sent', template_name)
return # just ignore if template doesn't exist
subject_part = from_string(
HELPDESK_EMAIL_SUBJECT_TEMPLATE % {
"subject": t.subject
}).render(context).replace('\n', '').replace('\r', '')
footer_file = os.path.join('helpdesk', locale, 'email_text_footer.txt')
text_part = from_string(
"%s{%% include '%s' %%}" % (t.plain_text, footer_file)
).render(context)
email_html_base_file = os.path.join('helpdesk', locale, 'email_html_base.html')
# keep new lines in html emails
if 'comment' in context:
context['comment'] = mark_safe(context['comment'].replace('\r\n', '<br>'))
html_part = from_string(
"{%% extends '%s' %%}{%% block title %%}"
"%s"
"{%% endblock %%}{%% block content %%}%s{%% endblock %%}" %
(email_html_base_file, t.heading, t.html)
).render(context)
if isinstance(recipients, str):
if recipients.find(','):
recipients = recipients.split(',')
elif type(recipients) != list:
recipients = [recipients]
msg = EmailMultiAlternatives(subject_part, text_part,
sender or settings.DEFAULT_FROM_EMAIL,
recipients, bcc=bcc)
msg.attach_alternative(html_part, "text/html")
if files:
for filename, filefield in files:
mime = mimetypes.guess_type(filename)
if mime[0] is not None and mime[0] == "text/plain":
with open(filefield.path, 'r') as attachedfile:
content = attachedfile.read()
msg.attach(filename, content)
else:
msg.attach_file(filefield.path)
logger.debug('Sending email to: {!r}'.format(recipients))
try:
return msg.send()
except SMTPException as e:
logger.exception('SMTPException raised while sending email to {}'.format(recipients))
if not fail_silently:
raise e
return 0