task group naming logic changed

src/asyncio_taskpool/internals/constants.py

@@ -25,8 +25,6 @@ PACKAGE_NAME = 'asyncio_taskpool'
 
 DEFAULT_TASK_GROUP = 'default'
 
-DATETIME_FORMAT = '%Y-%m-%d_%H-%M-%S'
-
 SESSION_MSG_BYTES = 1024 * 100
 
 STREAM_WRITER = 'stream_writer'

src/asyncio_taskpool/pool.py

@@ -33,12 +33,11 @@ from asyncio.exceptions import CancelledError
 from asyncio.locks import Semaphore
 from asyncio.tasks import Task, create_task, gather
 from contextlib import suppress
-from datetime import datetime
 from math import inf
 from typing import Any, Awaitable, Dict, Iterable, List, Set, Union
 
 from . import exceptions
-from .internals.constants import DEFAULT_TASK_GROUP, DATETIME_FORMAT
+from .internals.constants import DEFAULT_TASK_GROUP
 from .internals.group_register import TaskGroupRegister
 from .internals.helpers import execute_optional, star_function
 from .internals.types import ArgsT, KwArgsT, CoroutineFunc, EndCB, CancelCB
@@ -607,6 +606,7 @@ class TaskPool(BaseTaskPool):
         Raises:
             `PoolStillUnlocked`: The pool has not been locked yet.
         """
+        self.lock()
         not_cancelled_meta_tasks = (task for task_set in self._group_meta_tasks_running.values() for task in task_set)
         with suppress(CancelledError):
             await gather(*self._meta_tasks_cancelled, *not_cancelled_meta_tasks, return_exceptions=return_exceptions)
@@ -614,19 +614,24 @@ class TaskPool(BaseTaskPool):
         self._group_meta_tasks_running.clear()
         await super().gather_and_close(return_exceptions=return_exceptions)
 
-    @staticmethod
+    def _generate_group_name(self, prefix: str, coroutine_function: CoroutineFunc) -> str:
-    def _generate_group_name(prefix: str, coroutine_function: CoroutineFunc) -> str:
         """
-        Creates a task group identifier that includes the current datetime.
+        Creates a unique task group identifier.
 
         Args:
             prefix: The start of the name; will be followed by an underscore.
             coroutine_function: The function representing the task group.
 
         Returns:
-            The constructed 'prefix_function_datetime' string to name a task group.
+            The constructed 'prefix_function_index' string to name a task group.
         """
-        return f'{prefix}_{coroutine_function.__name__}_{datetime.now().strftime(DATETIME_FORMAT)}'
+        base_name = f'{prefix}_{coroutine_function.__name__}'
+        i = 0
+        while True:
+            name = f'{base_name}_{i}'
+            if name not in self._task_groups.keys():
+                return name
+            i += 1
 
     async def _apply_num(self, group_name: str, func: CoroutineFunc, args: ArgsT = (), kwargs: KwArgsT = None,
                          num: int = 1, end_callback: EndCB = None, cancel_callback: CancelCB = None) -> None:
@@ -682,7 +687,8 @@ class TaskPool(BaseTaskPool):
             num (optional):
                 The number of tasks to spawn with the specified parameters.
             group_name (optional):
-                Name of the task group to add the new tasks to.
+                Name of the task group to add the new tasks to. By default, a unique name is constructed using the
+                name of the provided `func` and an incrementing index as 'apply_func_index'.
             end_callback (optional):
                 A callback to execute after a task has ended.
                 It is run with the task's ID as its only positional argument.
@@ -691,7 +697,7 @@ class TaskPool(BaseTaskPool):
                 It is run with the task's ID as its only positional argument.
 
         Returns:
-            The name of the task group that the newly spawned tasks have been added to.
+            The name of the newly created task group (see the `group_name` parameter).
 
         Raises:
             `PoolIsClosed`: The pool is closed.
@@ -710,7 +716,7 @@ class TaskPool(BaseTaskPool):
 
     @staticmethod
     def _get_map_end_callback(map_semaphore: Semaphore, actual_end_callback: EndCB) -> EndCB:
-        """Returns a wrapped `end_callback` for each :meth:`_queue_consumer` task that releases the `map_semaphore`."""
+        """Returns a wrapped `end_callback` for each :meth:`_arg_consumer` task that releases the `map_semaphore`."""
         async def release_callback(task_id: int) -> None:
             map_semaphore.release()
             await execute_optional(actual_end_callback, args=(task_id,))
@@ -847,6 +853,8 @@ class TaskPool(BaseTaskPool):
                 The number new tasks spawned by this method to run concurrently. Defaults to 1.
             group_name (optional):
                 Name of the task group to add the new tasks to. If provided, it must be a name that doesn't exist yet.
+                By default, a unique name is constructed using the name of the provided `func` and an incrementing
+                index as 'apply_func_index'.
             end_callback (optional):
                 A callback to execute after a task has ended.
                 It is run with the task's ID as its only positional argument.
@@ -855,7 +863,7 @@ class TaskPool(BaseTaskPool):
                 It is run with the task's ID as its only positional argument.
 
         Returns:
-            The name of the task group that the newly spawned tasks will be added to.
+            The name of the newly created task group (see the `group_name` parameter).
 
         Raises:
             `PoolIsClosed`: The pool is closed.

tests/test_pool.py

@@ -20,13 +20,11 @@ Unittests for the `asyncio_taskpool.pool` module.
 
 from asyncio.exceptions import CancelledError
 from asyncio.locks import Semaphore
-from datetime import datetime
 from unittest import IsolatedAsyncioTestCase
 from unittest.mock import PropertyMock, MagicMock, AsyncMock, patch, call
 from typing import Type
 
 from asyncio_taskpool import pool, exceptions
-from asyncio_taskpool.internals.constants import DATETIME_FORMAT
 
 
 EMPTY_LIST, EMPTY_DICT, EMPTY_SET = [], {}, set()
@@ -363,7 +361,8 @@ class BaseTaskPoolTestCase(CommonTestCase):
         self.assertDictEqual(EMPTY_DICT, self.task_pool._tasks_ended)
         self.assertDictEqual(EMPTY_DICT, self.task_pool._tasks_cancelled)
 
-    async def test_gather_and_close(self):
+    @patch.object(pool.BaseTaskPool, 'lock')
+    async def test_gather_and_close(self, mock_lock: MagicMock):
         mock_running_func = AsyncMock()
         mock_ended_func, mock_cancelled_func = AsyncMock(), AsyncMock(side_effect=Exception)
         self.task_pool._tasks_ended = {123: mock_ended_func()}
@@ -372,6 +371,7 @@ class BaseTaskPoolTestCase(CommonTestCase):
 
         self.task_pool._locked = True
         self.assertIsNone(await self.task_pool.gather_and_close(return_exceptions=True))
+        mock_lock.assert_called_once_with()
         mock_ended_func.assert_awaited_once_with()
         mock_cancelled_func.assert_awaited_once_with()
         mock_running_func.assert_awaited_once_with()
@@ -458,13 +458,15 @@ class TaskPoolTestCase(CommonTestCase):
         mock_cancelled_meta_task.assert_awaited_once_with()
         self.assertSetEqual(EMPTY_SET, self.task_pool._meta_tasks_cancelled)
 
+    @patch.object(pool.BaseTaskPool, 'lock')
     @patch.object(pool.BaseTaskPool, 'gather_and_close')
-    async def test_gather_and_close(self, mock_base_gather_and_close: AsyncMock):
+    async def test_gather_and_close(self, mock_base_gather_and_close: AsyncMock, mock_lock: MagicMock):
         mock_meta_task1, mock_meta_task2 = AsyncMock(), AsyncMock()
         self.task_pool._group_meta_tasks_running = {FOO: {mock_meta_task1()}, BAR: {mock_meta_task2()}}
         mock_cancelled_meta_task = AsyncMock(side_effect=CancelledError)
         self.task_pool._meta_tasks_cancelled = {mock_cancelled_meta_task()}
         self.assertIsNone(await self.task_pool.gather_and_close(return_exceptions=True))
+        mock_lock.assert_called_once_with()
         mock_base_gather_and_close.assert_awaited_once_with(return_exceptions=True)
         mock_meta_task1.assert_awaited_once_with()
         mock_meta_task2.assert_awaited_once_with()
@@ -472,13 +474,15 @@ class TaskPoolTestCase(CommonTestCase):
         self.assertDictEqual(EMPTY_DICT, self.task_pool._group_meta_tasks_running)
         self.assertSetEqual(EMPTY_SET, self.task_pool._meta_tasks_cancelled)
 
-    @patch.object(pool, 'datetime')
+    def test__generate_group_name(self):
-    def test__generate_group_name(self, mock_datetime: MagicMock):
         prefix, func = 'x y z', AsyncMock(__name__=BAR)
-        dt = datetime(1776, 7, 4, 0, 0, 1)
+        self.task_pool._task_groups = {
-        mock_datetime.now = MagicMock(return_value=dt)
+            f'{prefix}_{BAR}_0': MagicMock(),
-        expected_output = f'{prefix}_{BAR}_{dt.strftime(DATETIME_FORMAT)}'
+            f'{prefix}_{BAR}_1': MagicMock(),
-        output = pool.TaskPool._generate_group_name(prefix, func)
+            f'{prefix}_{BAR}_100': MagicMock(),
+        }
+        expected_output = f'{prefix}_{BAR}_2'
+        output = self.task_pool._generate_group_name(prefix, func)
         self.assertEqual(expected_output, output)
 
     @patch.object(pool.TaskPool, '_start_task')