def Transform(self, client, device, callback):
from tornado.web import stack_context
from viewfinder.backend.db.device import Device
def _DoUpdate():
self._LogUpdate(device)
if Version._mutate_items:
device.Update(client, partial(callback, device))
else:
callback(device)
def _OnQueryByPushToken(other_devices):
# If another device with the same push token and with a greater id exists, then erase this
# device's push token.
for other in other_devices:
if other.push_token == device.push_token and other.device_id > device.device_id:
device.alert_user_id = None
device.push_token = None
break
_DoUpdate()
# Do not allow re-entrancy, which is caused by the Device.IndexQuery below. Put a
# ContextLocal into scope so that re-entrancy can be detected.
if InTransformContext.current() is None:
with stack_context.StackContext(InTransformContext()):
# Set the new device timestamp field.
device.timestamp = device.last_access or time.time()
if device.push_token is not None:
# Enable alerts if the device is still active.
if time.time(
) < device.last_access + Device._PUSH_EXPIRATION:
device.alert_user_id = device.user_id
# Find all devices with the same push token.
query_expr = ('device.push_token={t}', {
't': device.push_token
})
Device.IndexQuery(client, query_expr, None,
_OnQueryByPushToken)
else:
_DoUpdate()
else:
callback(device)
