feat: add feeluown.task module

Makefile

@@ -2,6 +2,7 @@ LINT_FILES = fuocore/
 LINT_FILES += feeluown/entry_points
 LINT_FILES += feeluown/app.py
 LINT_FILES += feeluown/ui.py
+LINT_FILES += feeluown/task.py
 LINT_FILES += feeluown/widgets/*_panel.py
 LINT_FILES += feeluown/widgets/table_container.py
 LINT_FILES += feeluown/widgets/songs_table.py

docs/source/api.rst

@@ -781,6 +781,9 @@ metadata 是 ``AudioMeta`` 的实例。对于视频文件，metadata 则是 ``Vi
 通用管理模块
 ----------------
 
+.. automodule:: feeluown.task
+ :members:
+
 .. automodule:: feeluown.version
 
 .. automodule:: feeluown.tips

feeluown/task.py

@@ -0,0 +1,101 @@
+import logging
+from enum import Enum
+
+logger = logging.getLogger(__name__)
+
+
+class TaskKind(Enum):
+ preemptive = 'preemptive' #: preemptive task
+ cooperative = 'cooperative' #: cooperative task
+
+
+class PreemptiveTaskSpec:
+ """Preemptive task specification"""
+
+ def __init__(self, mgr, name):
+ """
+
+ :param mgr: :class:`TaskManager`
+ :param name: task unique name
+ """
+ self._mgr = mgr
+ self.name = name
+ self.kind = TaskKind.preemptive
+ self._task = None
+
+ def _before_bind(self):
+ if self._task is None:
+ return
+ self._task.cancel()
+ logger.info('preemptive-task(%s): try to cancel previous', self.name)
+ self._task = None
+
+ def bind_coro(self, coro):
+ """run the coroutine and bind the task
+
+ it will cancel the previous task if exists
+
+ :return: :class:`asyncio.Task`
+ """
+ self._before_bind()
+ self._task = self._mgr.loop.create_task(coro)
+ return self._task
+
+ def bind_blocking_io(self, func, *args):
+ """run blocking io func in a thread executor, and bind the task
+
+ it will cancel the previous task if exists
+
+ :return: :class:`asyncio.Task`
+ """
+ self._before_bind()
+ self._task = self._mgr.loop.run_in_executor(None, func, *args)
+ return self._task
+
+
+class TaskManager:
+ """named task manager
+
+ Usage::
+
+ async def fetch_song():
+ pass
+
+ task_name = 'unique-name'
+
+ task_spec = task_mgr.get_or_create(task_name, TaskType.preemptive)
+ task = task_spec.bind_coro(fetch_song())
+ """
+ def __init__(self, app, loop):
+ """
+
+ :param app: feeluown app instance
+ :param loop: asyncio event loop
+ """
+ self._app = app
+
+ # only accessible for task instance
+ self.loop = loop
+
+ # store the name:taskspec mapping
+ self._store = {}
+
+ def get_or_create(self, name, kind=TaskKind.preemptive):
+ """get task spec, it will be created if not exists
+
+ :param name: task identifier(name)
+ :param kind: :class:`TaskKind`
+
+ TODO: client should register first, then get by name
+ """
+ if name not in self._store:
+ task_spec = self._create(name, kind)
+ else:
+ task_spec = self._store[name]
+ return task_spec
+
+ def _create(self, name, kind):
+ kind = TaskKind(kind)
+ task_spec = PreemptiveTaskSpec(self, name)
+ self._store[name] = task_spec
+ return task_spec

tests/feeluown/test_task.py

@@ -0,0 +1,44 @@
+import asyncio
+import time
+from unittest import mock
+
+import pytest
+
+from feeluown.task import TaskManager, PreemptiveTaskSpec
+
+
+@pytest.mark.asyncio
+async def test_task_manager(app_mock):
+ loop = asyncio.get_event_loop()
+ task_mgr = TaskManager(app_mock, loop)
+ task_spec = task_mgr.get_or_create('fetch-song-standby')
+
+ async def fetch_song():
+ pass
+
+ mock_done_cb = mock.MagicMock()
+ task = task_spec.bind_coro(fetch_song())
+ task.add_done_callback(mock_done_cb)
+ await asyncio.sleep(0.1) # let task run
+ assert mock_done_cb.called is True
+
+
+@pytest.mark.asyncio
+async def test_preemptive_task_spec_bind_coro():
+ mgr = mock.MagicMock()
+ loop = asyncio.get_event_loop()
+ mgr.loop = loop
+ task_spec = PreemptiveTaskSpec(mgr, 'fetch-song-standby')
+
+ mock_cancelled_cb = mock.MagicMock()
+
+ async def fetch_song():
+ try:
+ await asyncio.sleep(0.1)
+ except asyncio.CancelledError:
+ mock_cancelled_cb()
+
+ task_spec.bind_coro(fetch_song())
+ await asyncio.sleep(0.1) # let fetch_song run
+ await task_spec.bind_coro(fetch_song())
+ assert mock_cancelled_cb.called is True