Anki/qt/aqt/operations/__init__.py

355 lines
11 KiB
Python

# Copyright: Ankitects Pty Ltd and contributors
# License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
from __future__ import annotations
from concurrent.futures._base import Future
from typing import Any, Callable, Generic, Literal, Protocol, TypeVar, Union
import aqt
import aqt.gui_hooks
import aqt.main
from anki.collection import (
Collection,
ImportLogWithChanges,
OpChanges,
OpChangesAfterUndo,
OpChangesWithCount,
OpChangesWithId,
)
from aqt.errors import show_exception
from aqt.qt import QTimer, QWidget, qconnect
from aqt.utils import showWarning
class HasChangesProperty(Protocol):
changes: OpChanges
# either an OpChanges object, or an object with .changes on it. This bound
# doesn't actually work for protobuf objects, so new protobuf objects will
# either need to be added here, or cast at call time
ResultWithChanges = TypeVar(
"ResultWithChanges",
bound=Union[
OpChanges,
OpChangesWithCount,
OpChangesWithId,
OpChangesAfterUndo,
ImportLogWithChanges,
HasChangesProperty,
],
)
class CollectionOp(Generic[ResultWithChanges]):
"""Helper to perform a mutating DB operation on a background thread, and update UI.
`op` should either return OpChanges, or an object with a 'changes'
property. The changes will be passed to `operation_did_execute` so that
the UI can decide whether it needs to update itself.
- Shows progress popup for the duration of the op.
- Ensures the browser doesn't try to redraw during the operation, which can lead
to a frozen UI
- Updates undo state at the end of the operation
- Commits changes
- Fires the `operation_(will|did)_reset` hooks
- Fires the legacy `state_did_reset` hook
Be careful not to call any UI routines in `op`, as that may crash Qt.
This includes things select .selectedCards() in the browse screen.
`success` will be called with the return value of op().
If op() throws an exception, it will be shown in a popup, or
passed to `failure` if it is provided.
"""
_success: Callable[[ResultWithChanges], Any] | None = None
_failure: Callable[[Exception], Any] | None = None
def __init__(self, parent: QWidget, op: Callable[[Collection], ResultWithChanges]):
self._parent = parent
self._op = op
def success(
self, success: Callable[[ResultWithChanges], Any] | None
) -> CollectionOp[ResultWithChanges]:
self._success = success
return self
def failure(
self, failure: Callable[[Exception], Any] | None
) -> CollectionOp[ResultWithChanges]:
self._failure = failure
return self
def run_in_background(self, *, initiator: object | None = None) -> None:
from aqt import mw
assert mw
mw._increase_background_ops()
def wrapped_op() -> ResultWithChanges:
assert mw
return self._op(mw.col)
def wrapped_done(future: Future) -> None:
assert mw
mw._decrease_background_ops()
# did something go wrong?
if exception := future.exception():
if isinstance(exception, Exception):
if self._failure:
self._failure(exception)
else:
show_exception(parent=self._parent, exception=exception)
return
else:
# BaseException like SystemExit; rethrow it
future.result()
result = future.result()
try:
if self._success:
self._success(result)
finally:
self._finish_op(mw, result, initiator)
self._run(mw, wrapped_op, wrapped_done)
def _run(
self,
mw: aqt.main.AnkiQt,
op: Callable[[], ResultWithChanges],
on_done: Callable[[Future], None],
) -> None:
mw.taskman.with_progress(op, on_done)
def _finish_op(
self, mw: aqt.main.AnkiQt, result: ResultWithChanges, initiator: object | None
) -> None:
mw.update_undo_actions()
mw.autosave()
# fire change hooks
self._fire_change_hooks_after_op_performed(result, initiator)
def _fire_change_hooks_after_op_performed(
self,
result: ResultWithChanges,
handler: object | None,
) -> None:
from aqt import mw
assert mw
if isinstance(result, OpChanges):
changes = result
else:
changes = result.changes # type: ignore[union-attr]
# fire new hook
aqt.gui_hooks.operation_did_execute(changes, handler)
# fire legacy hook so old code notices changes
if mw.col.op_made_changes(changes):
aqt.gui_hooks.state_did_reset()
T = TypeVar("T")
class QueryOp(Generic[T]):
"""Helper to perform an operation on a background thread.
QueryOp is primarily used for read-only requests (reading information
from the database, fetching data from the network, etc), but can also
be used for mutable requests outside of the collection undo system
(eg adding/deleting files, calling a collection method that doesn't support
undo, etc). For operations that support undo, use CollectionOp instead.
- Optionally shows progress popup for the duration of the op.
- Ensures the browser doesn't try to redraw during the operation, which can lead
to a frozen UI
Be careful not to call any UI routines in `op`, as that may crash Qt.
This includes things like .selectedCards() in the browse screen.
`success` will be called with the return value of op().
If op() throws an exception, it will be shown in a popup, or
passed to `failure` if it is provided.
"""
_failure: Callable[[Exception], Any] | None = None
_progress: bool | str = False
def __init__(
self,
*,
parent: QWidget,
op: Callable[[Collection], T],
success: Callable[[T], Any],
):
self._parent = parent
self._op = op
self._success = success
def failure(self, failure: Callable[[Exception], Any] | None) -> QueryOp[T]:
self._failure = failure
return self
def with_progress(
self,
label: str | None = None,
) -> QueryOp[T]:
"If label not provided, will default to 'Processing...'"
self._progress = label or True
return self
def run_in_background(self) -> None:
from aqt import mw
assert mw
mw._increase_background_ops()
def wrapped_op() -> T:
assert mw
if self._progress:
label: str | None
if isinstance(self._progress, str):
label = self._progress
else:
label = None
def start_progress() -> None:
assert mw
mw.progress.start(label=label)
mw.taskman.run_on_main(start_progress)
return self._op(mw.col)
def wrapped_done(future: Future) -> None:
assert mw
if self._progress:
mw.progress.finish()
mw._decrease_background_ops()
# did something go wrong?
if exception := future.exception():
if isinstance(exception, Exception):
if self._failure:
self._failure(exception)
else:
showWarning(str(exception), self._parent)
return
else:
# BaseException like SystemExit; rethrow it
future.result()
self._success(future.result())
mw.taskman.run_in_background(wrapped_op, wrapped_done)
class CollectionOpWithBackendProgress(CollectionOp):
"""Periodically queries the backend for progress updates, and enables abortion.
Requires a key for a string value on the `Progress` proto message."""
def __init__(
self,
parent: QWidget,
op: Callable[[Collection], ResultWithChanges],
*args: Any,
key: Literal["importing"],
**kwargs: Any,
):
self._key = key
self.timer = QTimer()
self.timer.setSingleShot(False)
self.timer.setInterval(100)
super().__init__(parent, op, *args, **kwargs)
def _run(
self,
mw: aqt.main.AnkiQt,
op: Callable[[], ResultWithChanges],
on_done: Callable[[Future], None],
) -> None:
if not (dialog := mw.progress.start(immediate=True)):
print("Progress dialog already running; aborting will not work")
def on_progress() -> None:
assert mw
progress = mw.backend.latest_progress()
if not progress.HasField(self._key):
return
label = getattr(progress, self._key)
if dialog and dialog.wantCancel:
mw.backend.set_wants_abort()
mw.taskman.run_on_main(lambda: mw.progress.update(label=label))
def wrapped_on_done(future: Future) -> None:
self.timer.deleteLater()
assert mw
mw.progress.finish()
on_done(future)
qconnect(self.timer.timeout, on_progress)
self.timer.start()
mw.taskman.run_in_background(task=op, on_done=wrapped_on_done)
class ClosedCollectionOp(CollectionOp):
"""For CollectionOps that need to be run on a closed collection.
If a collection is open, backs it up and unloads it, before running the op.
Reloads it, if that has not been done by a callback, yet.
"""
def __init__(
self,
parent: QWidget,
op: Callable[[], ResultWithChanges],
*args: Any,
**kwargs: Any,
):
super().__init__(parent, lambda _: op(), *args, **kwargs)
def _run(
self,
mw: aqt.main.AnkiQt,
op: Callable[[], ResultWithChanges],
on_done: Callable[[Future], None],
) -> None:
if mw.col:
QueryOp(
parent=mw,
op=lambda _: mw.create_backup_now(),
success=lambda _: mw.unloadCollection(
lambda: super(ClosedCollectionOp, self)._run(mw, op, on_done)
),
).with_progress().run_in_background()
else:
super()._run(mw, op, on_done)
def _finish_op(
self,
_mw: aqt.main.AnkiQt,
_result: ResultWithChanges,
_initiator: object | None,
) -> None:
pass
class ClosedCollectionOpWithBackendProgress(
ClosedCollectionOp, CollectionOpWithBackendProgress
):
"""See ClosedCollectionOp and CollectionOpWithBackendProgress."""