artiq/artiq/gui/state.py

86 lines
2.7 KiB
Python

import asyncio
from collections import OrderedDict
import logging
from artiq.tools import TaskObject
from artiq.protocols import pyon
logger = logging.getLogger(__name__)
# support Qt CamelCase naming scheme for save/restore state
def _save_state(obj):
method = getattr(obj, "save_state", None)
if method is None:
method = obj.saveState
return method()
def _restore_state(obj, state):
method = getattr(obj, "restore_state", None)
if method is None:
method = obj.restoreState
method(state)
class StateManager(TaskObject):
def __init__(self, filename, autosave_period=30):
self.filename = filename
self.autosave_period = autosave_period
self.stateful_objects = OrderedDict()
def register(self, obj, name=None):
if name is None:
name = obj.__class__.__name__
if name in self.stateful_objects:
raise RuntimeError("Name '{}' already exists in state"
.format(name))
self.stateful_objects[name] = obj
def load(self):
try:
data = pyon.load_file(self.filename)
except FileNotFoundError:
logger.info("State database '%s' not found, using defaults",
self.filename)
return
# The state of one object may depend on the state of another,
# e.g. the display state may create docks that are referenced in
# the area state.
# To help address this problem, state is restored in the opposite
# order as the stateful objects are registered.
for name, obj in reversed(list(self.stateful_objects.items())):
logger.debug("Restoring state of object '%s'", name)
state = data.get(name, None)
if state is not None:
try:
_restore_state(obj, state)
except:
logger.warning("Failed to restore state for object '%s'",
name, exc_info=True)
def save(self):
data = dict()
for k, v in self.stateful_objects.items():
try:
data[k] = _save_state(v)
except:
logger.warning("Failed to save state for object '%s'", k,
exc_info=True)
pyon.store_file(self.filename, data)
async def _do(self):
try:
try:
while True:
await asyncio.sleep(self.autosave_period)
self.save()
finally:
self.save()
except asyncio.CancelledError:
pass
except:
logger.error("Uncaught exception attempting to save state",
exc_info=True)