full unit test coverage and docstrings for session_parser module; minor changes

This commit is contained in:
Daniil Fajnberg 2022-02-14 22:11:31 +01:00
parent 96d01e7259
commit bac7b32342
6 changed files with 215 additions and 14 deletions

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@ -1,6 +1,6 @@
[metadata]
name = asyncio-taskpool
version = 0.3.3
version = 0.3.4
author = Daniil Fajnberg
author_email = mail@daniil.fajnberg.de
description = Dynamically manage pools of asyncio tasks

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@ -24,7 +24,7 @@ PACKAGE_NAME = 'asyncio_taskpool'
CLIENT_EXIT = 'exit'
SESSION_MSG_BYTES = 1024 * 100
SESSION_PARSER_WRITER = 'session_writer'
SESSION_WRITER = 'session_writer'
class CLIENT_INFO:

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@ -25,7 +25,7 @@ from argparse import ArgumentError, HelpFormatter
from asyncio.streams import StreamReader, StreamWriter
from typing import Callable, Optional, Union, TYPE_CHECKING
from .constants import CMD, SESSION_PARSER_WRITER, SESSION_MSG_BYTES, CLIENT_INFO
from .constants import CMD, SESSION_WRITER, SESSION_MSG_BYTES, CLIENT_INFO
from .exceptions import HelpRequested, NotATaskPool, UnknownTaskPoolClass
from .helpers import get_first_doc_line, return_or_exception, tasks_str
from .pool import BaseTaskPool, TaskPool, SimpleTaskPool
@ -166,7 +166,7 @@ class ControlSession:
"""
parser_kwargs = {
'prog': '',
SESSION_PARSER_WRITER: self._writer,
SESSION_WRITER: self._writer,
CLIENT_INFO.TERMINAL_WIDTH: client_terminal_width,
}
self._parser = CommandParser(**parser_kwargs)

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@ -1,8 +1,29 @@
__author__ = "Daniil Fajnberg"
__copyright__ = "Copyright © 2022 Daniil Fajnberg"
__license__ = """GNU LGPLv3.0
This file is part of asyncio-taskpool.
asyncio-taskpool is free software: you can redistribute it and/or modify it under the terms of
version 3.0 of the GNU Lesser General Public License as published by the Free Software Foundation.
asyncio-taskpool is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along with asyncio-taskpool.
If not, see <https://www.gnu.org/licenses/>."""
__doc__ = """
This module contains the the definition of the `CommandParser` class used in a control server session.
"""
from argparse import Action, ArgumentParser, ArgumentDefaultsHelpFormatter, HelpFormatter
from asyncio.streams import StreamWriter
from typing import Type, TypeVar
from .constants import SESSION_PARSER_WRITER, CLIENT_INFO
from .constants import SESSION_WRITER, CLIENT_INFO
from .exceptions import HelpRequested
@ -12,8 +33,33 @@ NUM = 'num'
class CommandParser(ArgumentParser):
"""
Subclass of the standard `argparse.ArgumentParser` for remote interaction.
Such a parser is not supposed to ever print to stdout/stderr, but instead direct all messages to a `StreamWriter`
instance passed to it during initialization.
Furthermore, it requires defining the width of the terminal, to adjust help formatting to the terminal size of a
connected client.
Finally, it offers some convenience methods and makes use of custom exceptions.
"""
@staticmethod
def help_formatter_factory(terminal_width: int, base_cls: FmtCls = None) -> FmtCls:
"""
Constructs and returns a subclass of `argparse.HelpFormatter` with a fixed terminal width argument.
Although a custom formatter class can be explicitly passed into the `ArgumentParser` constructor, this is not
as convenient, when making use of sub-parsers.
Args:
terminal_width:
The number of columns of the terminal to which to adjust help formatting.
base_cls (optional):
The base class to use for inheritance. By default `argparse.ArgumentDefaultsHelpFormatter` is used.
Returns:
The subclass of `base_cls` which fixes the constructor's `width` keyword-argument to `terminal_width`.
"""
if base_cls is None:
base_cls = ArgumentDefaultsHelpFormatter
@ -23,35 +69,56 @@ class CommandParser(ArgumentParser):
super().__init__(*args, **kwargs)
return ClientHelpFormatter
def __init__(self, *args, **kwargs) -> None:
parent: CommandParser = kwargs.pop('parent', None)
self._stream_writer: StreamWriter = parent.stream_writer if parent else kwargs.pop(SESSION_PARSER_WRITER)
def __init__(self, parent: 'CommandParser' = None, **kwargs) -> None:
"""
Sets additional internal attributes depending on whether a parent-parser was defined.
The `help_formatter_factory` is called and the returned class is mapped to the `FORMATTER_CLASS` keyword.
By default, `exit_on_error` is set to `False` (as opposed to how the parent class handles it).
Args:
parent (optional):
An instance of the same class. Intended to be passed as a keyword-argument into the `add_parser` method
of the subparsers action returned by the `ArgumentParser.add_subparsers` method. If this is present,
the `SESSION_WRITER` and `CLIENT_INFO.TERMINAL_WIDTH` keywords must not be present in `kwargs`.
**kwargs(optional):
In addition to the regular `ArgumentParser` constructor parameters, this method expects the instance of
the `StreamWriter` as well as the terminal width both to be passed explicitly, if the `parent` argument
is empty.
"""
self._session_writer: StreamWriter = parent.session_writer if parent else kwargs.pop(SESSION_WRITER)
self._terminal_width: int = parent.terminal_width if parent else kwargs.pop(CLIENT_INFO.TERMINAL_WIDTH)
kwargs[FORMATTER_CLASS] = self.help_formatter_factory(self._terminal_width, kwargs.get(FORMATTER_CLASS))
kwargs.setdefault('exit_on_error', False)
super().__init__(*args, **kwargs)
super().__init__(**kwargs)
@property
def stream_writer(self) -> StreamWriter:
return self._stream_writer
def session_writer(self) -> StreamWriter:
"""Returns the predefined stream writer object of the control session."""
return self._session_writer
@property
def terminal_width(self) -> int:
"""Returns the predefined terminal width."""
return self._terminal_width
def _print_message(self, message: str, *args, **kwargs) -> None:
"""This is overridden to ensure that no messages are sent to stdout/stderr, but always to the stream writer."""
if message:
self.stream_writer.write(message.encode())
self._session_writer.write(message.encode())
def exit(self, status: int = 0, message: str = None) -> None:
"""This is overridden to prevent system exit to be invoked."""
if message:
self._print_message(message)
def print_help(self, file=None) -> None:
"""This just adds the custom `HelpRequested` exception after the parent class' method."""
super().print_help(file)
raise HelpRequested
def add_optional_num_argument(self, *name_or_flags: str, **kwargs) -> Action:
"""Convenience method for `add_argument` setting the name, `nargs`, `default`, and `type`, unless specified."""
if not name_or_flags:
name_or_flags = (NUM, )
kwargs.setdefault('nargs', '?')

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@ -25,7 +25,7 @@ from unittest import IsolatedAsyncioTestCase
from unittest.mock import AsyncMock, MagicMock, patch, call
from asyncio_taskpool import session
from asyncio_taskpool.constants import CLIENT_INFO, CMD, SESSION_MSG_BYTES, SESSION_PARSER_WRITER
from asyncio_taskpool.constants import CLIENT_INFO, CMD, SESSION_MSG_BYTES, SESSION_WRITER
from asyncio_taskpool.exceptions import HelpRequested, NotATaskPool, UnknownTaskPoolClass
from asyncio_taskpool.pool import BaseTaskPool, TaskPool, SimpleTaskPool
@ -119,7 +119,7 @@ class ControlServerTestCase(IsolatedAsyncioTestCase):
width = 1234
expected_parser_kwargs = {
'prog': '',
SESSION_PARSER_WRITER: self.mock_writer,
SESSION_WRITER: self.mock_writer,
CLIENT_INFO.TERMINAL_WIDTH: width,
}
self.assertIsNone(self.session._init_parser(width))

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@ -0,0 +1,134 @@
__author__ = "Daniil Fajnberg"
__copyright__ = "Copyright © 2022 Daniil Fajnberg"
__license__ = """GNU LGPLv3.0
This file is part of asyncio-taskpool.
asyncio-taskpool is free software: you can redistribute it and/or modify it under the terms of
version 3.0 of the GNU Lesser General Public License as published by the Free Software Foundation.
asyncio-taskpool is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along with asyncio-taskpool.
If not, see <https://www.gnu.org/licenses/>."""
__doc__ = """
Unittests for the `asyncio_taskpool.session_parser` module.
"""
from argparse import Action, ArgumentParser, HelpFormatter, ArgumentDefaultsHelpFormatter, RawTextHelpFormatter
from unittest import IsolatedAsyncioTestCase
from unittest.mock import MagicMock, patch
from asyncio_taskpool import session_parser
from asyncio_taskpool.constants import SESSION_WRITER, CLIENT_INFO
from asyncio_taskpool.exceptions import HelpRequested
FOO = 'foo'
class ControlServerTestCase(IsolatedAsyncioTestCase):
def setUp(self) -> None:
self.help_formatter_factory_patcher = patch.object(session_parser.CommandParser, 'help_formatter_factory')
self.mock_help_formatter_factory = self.help_formatter_factory_patcher.start()
self.mock_help_formatter_factory.return_value = RawTextHelpFormatter
self.session_writer, self.terminal_width = MagicMock(), 420
self.kwargs = {
SESSION_WRITER: self.session_writer,
CLIENT_INFO.TERMINAL_WIDTH: self.terminal_width,
session_parser.FORMATTER_CLASS: FOO
}
self.parser = session_parser.CommandParser(**self.kwargs)
def tearDown(self) -> None:
self.help_formatter_factory_patcher.stop()
def test_help_formatter_factory(self):
self.help_formatter_factory_patcher.stop()
class MockBaseClass(HelpFormatter):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
terminal_width = 123456789
cls = session_parser.CommandParser.help_formatter_factory(terminal_width, MockBaseClass)
self.assertTrue(issubclass(cls, MockBaseClass))
instance = cls('prog')
self.assertEqual(terminal_width, getattr(instance, '_width'))
cls = session_parser.CommandParser.help_formatter_factory(terminal_width)
self.assertTrue(issubclass(cls, ArgumentDefaultsHelpFormatter))
instance = cls('prog')
self.assertEqual(terminal_width, getattr(instance, '_width'))
def test_init(self):
self.assertIsInstance(self.parser, ArgumentParser)
self.assertEqual(self.session_writer, self.parser._session_writer)
self.assertEqual(self.terminal_width, self.parser._terminal_width)
self.mock_help_formatter_factory.assert_called_once_with(self.terminal_width, FOO)
self.assertFalse(getattr(self.parser, 'exit_on_error'))
self.assertEqual(RawTextHelpFormatter, getattr(self.parser, 'formatter_class'))
def test_session_writer(self):
self.assertEqual(self.session_writer, self.parser.session_writer)
def test_terminal_width(self):
self.assertEqual(self.terminal_width, self.parser.terminal_width)
def test__print_message(self):
self.session_writer.write = MagicMock()
self.assertIsNone(self.parser._print_message(''))
self.session_writer.write.assert_not_called()
msg = 'foo bar baz'
self.assertIsNone(self.parser._print_message(msg))
self.session_writer.write.assert_called_once_with(msg.encode())
@patch.object(session_parser.CommandParser, '_print_message')
def test_exit(self, mock__print_message: MagicMock):
self.assertIsNone(self.parser.exit(123, ''))
mock__print_message.assert_not_called()
msg = 'foo bar baz'
self.assertIsNone(self.parser.exit(123, msg))
mock__print_message.assert_called_once_with(msg)
@patch.object(session_parser.ArgumentParser, 'print_help')
def test_print_help(self, mock_print_help: MagicMock):
arg = MagicMock()
with self.assertRaises(HelpRequested):
self.parser.print_help(arg)
mock_print_help.assert_called_once_with(arg)
def test_add_optional_num_argument(self):
metavar = 'FOOBAR'
action = self.parser.add_optional_num_argument(metavar=metavar)
self.assertIsInstance(action, Action)
self.assertEqual('?', action.nargs)
self.assertEqual(1, action.default)
self.assertEqual(int, action.type)
self.assertEqual(metavar, action.metavar)
num = 111
kwargs = vars(self.parser.parse_args([f'{num}']))
self.assertDictEqual({session_parser.NUM: num}, kwargs)
name = f'--{FOO}'
nargs = '+'
default = 1
_type = float
required = True
dest = 'foo_bar'
action = self.parser.add_optional_num_argument(name, nargs=nargs, default=default, type=_type,
required=required, metavar=metavar, dest=dest)
self.assertIsInstance(action, Action)
self.assertEqual(nargs, action.nargs)
self.assertEqual(default, action.default)
self.assertEqual(_type, action.type)
self.assertEqual(required, action.required)
self.assertEqual(metavar, action.metavar)
self.assertEqual(dest, action.dest)
kwargs = vars(self.parser.parse_args([f'{num}', name, '1', '1.5']))
self.assertDictEqual({session_parser.NUM: num, dest: [1.0, 1.5]}, kwargs)