Files
zulip/zerver/lib/bot_storage.py
2017-11-21 21:10:39 -08:00

60 lines
2.6 KiB
Python

from django.conf import settings
from django.db.models import Sum
from django.db.models.query import F
from django.db.models.functions import Length
from zerver.models import BotUserStateData, UserProfile, Length
from typing import Text, Optional, List, Tuple
class StateError(Exception):
pass
def get_bot_state(bot_profile, key):
# type: (UserProfile, Text) -> Text
try:
return BotUserStateData.objects.get(bot_profile=bot_profile, key=key).value
except BotUserStateData.DoesNotExist:
raise StateError("Key does not exist.")
def get_bot_state_size(bot_profile, key=None):
# type: (UserProfile, Optional[Text]) -> int
if key is None:
return BotUserStateData.objects.filter(bot_profile=bot_profile) \
.annotate(key_size=Length('key'), value_size=Length('value')) \
.aggregate(sum=Sum(F('key_size')+F('value_size')))['sum'] or 0
else:
try:
return len(key) + len(BotUserStateData.objects.get(bot_profile=bot_profile, key=key).value)
except BotUserStateData.DoesNotExist:
return 0
def set_bot_state(bot_profile, entries):
# type: (UserProfile, List[Tuple[str, str]]) -> None
state_size_limit = settings.USER_STATE_SIZE_LIMIT
state_size_difference = 0
for key, value in entries:
if type(key) is not str:
raise StateError("Key type is {}, but should be str.".format(type(key)))
if type(value) is not str:
raise StateError("Value type is {}, but should be str.".format(type(value)))
state_size_difference += (len(key) + len(value)) - get_bot_state_size(bot_profile, key)
new_state_size = get_bot_state_size(bot_profile) + state_size_difference
if new_state_size > state_size_limit:
raise StateError("Request exceeds storage limit by {} characters. The limit is {} characters."
.format(new_state_size - state_size_limit, state_size_limit))
else:
for key, value in entries:
BotUserStateData.objects.update_or_create(bot_profile=bot_profile, key=key,
defaults={'value': value})
def remove_bot_state(bot_profile, keys):
# type: (UserProfile, List[Text]) -> None
queryset = BotUserStateData.objects.filter(bot_profile=bot_profile, key__in=keys)
if len(queryset) < len(keys):
raise StateError("Key does not exist.")
queryset.delete()
def is_key_in_bot_state(bot_profile, key):
# type: (UserProfile, Text) -> bool
return BotUserStateData.objects.filter(bot_profile=bot_profile, key=key).exists()