def create_message(sender, recipient, subject, body='', skip_notification=False, auto_archive=False, auto_delete=False, auto_moderators=None, sent_at=None):
if not user_is_valid(sender):
raise InvalidSenderException()
if not user_is_valid(recipient):
raise InvalidRecipientException()
if subject is None or subject == '':
raise NoMessageSubjectException('this message has an empty subject line. Messages without subject cannot be sent')
if body is None or body == '':
raise NoMessageBodyException('this message has an empty message body. Empty message cannot be sent')
message = Message(subject=subject, body=body, sender=sender, recipient=recipient)
if not sent_at is None:
message.sent_at = sent_at
initial_status = message.moderation_status
if auto_moderators:
message.auto_moderate(auto_moderators)
else:
message.moderation_status = STATUS_ACCEPTED
message.clean_moderation(initial_status)
if auto_archive:
message.sender_archived = True
if auto_delete:
message.sender_deleted_at = now()
message.save()
if not skip_notification:
message.notify_users(initial_status, _get_site())
return message
