def send_friend_request(cls, sender_id, friend_id):
result = enki.libutil.ENKILIB_OK
if friend_id != sender_id: # friend is not me
if not cls.exist_by_user_ids(
sender_id, friend_id): # we're not currently friends
already_invited = EnkiModelMessage.get_key_by_sender_recipient(
friend_id, sender_id)
if already_invited:
# if an invite from the potential friend already exists, add the pair of friends immediately and delete the invite(s)
cls.add_friend(sender_id, friend_id)
result = cls.INFO_FRIENDS
# send an invitation to friend (unless it's a duplicate)
elif not EnkiModelMessage.exist_by_sender_recipient(
sender_id, friend_id):
EnkiModelMessage.send_message(sender_id, friend_id,
'friend_request')
else:
result = EnkiModelDisplayName.ERROR_DISPLAY_NAME_INVALID
return result
