Send e-mails on order completion (#27)

src/pretix/base/mail.py

@@ -0,0 +1,51 @@
+import logging
+from django.conf import settings
+from django.core.mail import EmailMessage
+from django.template.loader import get_template
+from django.utils import translation
+
+from pretix.base.models import User, Event
+
+logger = logging.getLogger('pretix.base.mail')
+
+
+def mail(user: User, subject: str, template: str, context: dict, event: Event=None):
+    """
+    Sends out an email to a user.
+
+    :param user: The user this should be sent to.
+    :param subject: The e-mail subject. Should be localized.
+    :param template: The filename of a template to be used. It will
+                     be rendered with the recipient's locale.
+    :param context: The context for rendering the template.
+    :param event: The event, used for determining the sender of the e-mail
+
+    :return: ``False`` on obvious failures, like the user having to e-mail
+    address, ``True`` otherwise. ``True`` does not necessarily mean that
+    the email has been sent, just that it has been queued by the e-mail
+    backend.
+    """
+    if not user.email:
+        return False
+
+    _lng = translation.get_language()
+    translation.activate(user.locale or settings.LANGUAGE_CODE)
+
+    tpl = get_template(template)
+    body = tpl.render(context)
+
+    sender = event.settings.get('mail_from') if event else settings.MAIL_FROM
+
+    email = EmailMessage(
+        subject, body, sender,
+        to=[user.email]
+    )
+
+    try:
+        email.send(fail_silently=False)
+        return True
+    except Exception:
+        logger.exception('Error sending e-mail')
+        return False
+    finally:
+        translation.activate(_lng)

src/pretix/base/payment.py

@@ -248,6 +248,16 @@ class BasePaymentProvider:
         """
         return None
 
+    def order_pending_mail_render(self, order: Order) -> str:
+        """
+        After the user submitted his order, he or she will receive a confirmation
+        e-mail. You can return a string from this method if you want to add additional
+        information to this e-mail.
+
+        :param order: The order object
+        """
+        return ""
+
     def order_pending_render(self, request: HttpRequest, order: Order) -> str:
         """
         If the user visits a detail page of an order which has not yet been paid but

src/pretix/base/settings.py

@@ -4,6 +4,7 @@ import decimal
 
 import dateutil.parser
 from django.db.models import Model
+from django.conf import settings
 from versions.models import Versionable
 
 
@@ -14,6 +15,7 @@ DEFAULTS = {
     'attendee_names_required': 'False',
     'reservation_time': '30',
     'last_order_modification_date': None,
+    'mail_from': settings.MAIL_FROM,
 }