generated from daniil-berg/boilerplate-py
massive overhaul of the control server interface;
making use of `ArgumentParser` for client commands; new `ControlSession` object instantiated upon connection
This commit is contained in:
218
src/asyncio_taskpool/session.py
Normal file
218
src/asyncio_taskpool/session.py
Normal file
@ -0,0 +1,218 @@
|
||||
import logging
|
||||
import json
|
||||
from argparse import ArgumentError, ArgumentParser, HelpFormatter, Namespace
|
||||
from asyncio.streams import StreamReader, StreamWriter
|
||||
from typing import Callable, Optional, Type, Union, TYPE_CHECKING
|
||||
|
||||
from . import constants
|
||||
from .exceptions import HelpRequested
|
||||
from .helpers import get_first_doc_line, return_or_exception, tasks_str
|
||||
from .pool import TaskPool, SimpleTaskPool
|
||||
|
||||
if TYPE_CHECKING:
|
||||
from .server import ControlServer
|
||||
|
||||
|
||||
log = logging.getLogger(__name__)
|
||||
|
||||
NUM = 'num'
|
||||
WIDTH = 'width'
|
||||
|
||||
|
||||
class CommandParser(ArgumentParser):
|
||||
@staticmethod
|
||||
def help_formatter_factory(terminal_width: int) -> Type[HelpFormatter]:
|
||||
class ClientHelpFormatter(HelpFormatter):
|
||||
def __init__(self, *args, **kwargs) -> None:
|
||||
kwargs[WIDTH] = terminal_width
|
||||
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('writer')
|
||||
self._terminal_width: int = parent.terminal_width if parent else kwargs.pop(WIDTH)
|
||||
kwargs.setdefault('formatter_class', self.help_formatter_factory(self._terminal_width))
|
||||
kwargs.setdefault('exit_on_error', False)
|
||||
super().__init__(*args, **kwargs)
|
||||
|
||||
@property
|
||||
def stream_writer(self) -> StreamWriter:
|
||||
return self._stream_writer
|
||||
|
||||
@property
|
||||
def terminal_width(self) -> int:
|
||||
return self._terminal_width
|
||||
|
||||
def _print_message(self, message: str, *args, **kwargs) -> None:
|
||||
if message:
|
||||
self.stream_writer.write(message.encode())
|
||||
|
||||
def exit(self, status: int = 0, message: str = None) -> None:
|
||||
if message:
|
||||
self._print_message(message)
|
||||
|
||||
def print_help(self, file=None) -> None:
|
||||
super().print_help(file)
|
||||
raise HelpRequested
|
||||
|
||||
|
||||
class ControlSession:
|
||||
def __init__(self, server: 'ControlServer', reader: StreamReader, writer: StreamWriter) -> None:
|
||||
self._control_server: 'ControlServer' = server
|
||||
self._pool: Union[TaskPool, SimpleTaskPool] = server.pool
|
||||
self._client_class_name = server.client_class_name
|
||||
self._reader: StreamReader = reader
|
||||
self._writer: StreamWriter = writer
|
||||
self._parser: Optional[CommandParser] = None
|
||||
|
||||
def _add_base_commands(self):
|
||||
subparsers = self._parser.add_subparsers(title="Commands", dest=constants.CMD)
|
||||
subparsers.add_parser(
|
||||
constants.CMD_NAME,
|
||||
prog=constants.CMD_NAME,
|
||||
help=get_first_doc_line(self._pool.__class__.__str__),
|
||||
parent=self._parser,
|
||||
)
|
||||
subparser_pool_size = subparsers.add_parser(
|
||||
constants.CMD_POOL_SIZE,
|
||||
prog=constants.CMD_POOL_SIZE,
|
||||
help="Get/set the maximum number of tasks in the pool",
|
||||
parent=self._parser,
|
||||
)
|
||||
subparser_pool_size.add_argument(
|
||||
NUM,
|
||||
nargs='?',
|
||||
help=f"If passed a number: {get_first_doc_line(self._pool.__class__.pool_size.fset)} "
|
||||
f"If omitted: {get_first_doc_line(self._pool.__class__.pool_size.fget)}"
|
||||
)
|
||||
subparsers.add_parser(
|
||||
constants.CMD_NUM_RUNNING,
|
||||
help=get_first_doc_line(self._pool.__class__.num_running.fget),
|
||||
parent=self._parser,
|
||||
)
|
||||
return subparsers
|
||||
|
||||
def _add_simple_commands(self):
|
||||
subparsers = self._add_base_commands()
|
||||
subparser = subparsers.add_parser(
|
||||
constants.CMD_START,
|
||||
prog=constants.CMD_START,
|
||||
help=get_first_doc_line(self._pool.__class__.start),
|
||||
parent=self._parser,
|
||||
)
|
||||
subparser.add_argument(
|
||||
NUM,
|
||||
nargs='?',
|
||||
type=int,
|
||||
default=1,
|
||||
help="Number of tasks to start. Defaults to 1."
|
||||
)
|
||||
subparser = subparsers.add_parser(
|
||||
constants.CMD_STOP,
|
||||
prog=constants.CMD_STOP,
|
||||
help=get_first_doc_line(self._pool.__class__.stop),
|
||||
parent=self._parser,
|
||||
)
|
||||
subparser.add_argument(
|
||||
NUM,
|
||||
nargs='?',
|
||||
type=int,
|
||||
default=1,
|
||||
help="Number of tasks to stop. Defaults to 1."
|
||||
)
|
||||
subparsers.add_parser(
|
||||
constants.CMD_STOP_ALL,
|
||||
prog=constants.CMD_STOP_ALL,
|
||||
help=get_first_doc_line(self._pool.__class__.stop_all),
|
||||
parent=self._parser,
|
||||
)
|
||||
subparsers.add_parser(
|
||||
constants.CMD_FUNC_NAME,
|
||||
prog=constants.CMD_FUNC_NAME,
|
||||
help=get_first_doc_line(self._pool.__class__.func_name.fget),
|
||||
parent=self._parser,
|
||||
)
|
||||
|
||||
def _init_parser(self, client_terminal_width: int) -> None:
|
||||
self._parser = CommandParser(prog='', writer=self._writer, width=client_terminal_width)
|
||||
if isinstance(self._pool, TaskPool):
|
||||
pass # TODO
|
||||
elif isinstance(self._pool, SimpleTaskPool):
|
||||
self._add_simple_commands()
|
||||
|
||||
async def client_handshake(self) -> None:
|
||||
client_info = json.loads((await self._reader.read(constants.MSG_BYTES)).decode().strip())
|
||||
log.debug("%s connected", self._client_class_name)
|
||||
self._init_parser(client_info[WIDTH])
|
||||
self._writer.write(str(self._pool).encode())
|
||||
await self._writer.drain()
|
||||
|
||||
async def _write_function_output(self, func: Callable, *args, **kwargs) -> None:
|
||||
output = await return_or_exception(func, *args, **kwargs)
|
||||
self._writer.write(b"ok" if output is None else str(output).encode())
|
||||
|
||||
async def _cmd_name(self, **_kwargs) -> None:
|
||||
log.debug("%s requests task pool name", self._client_class_name)
|
||||
await self._write_function_output(self._pool.__class__.__str__, self._pool)
|
||||
|
||||
async def _cmd_pool_size(self, **kwargs) -> None:
|
||||
num = kwargs.get(NUM)
|
||||
if num is None:
|
||||
log.debug("%s requests pool size", self._client_class_name)
|
||||
await self._write_function_output(self._pool.__class__.pool_size.fget, self._pool)
|
||||
else:
|
||||
log.debug("%s requests setting pool size to %s", self._client_class_name, num)
|
||||
await self._write_function_output(self._pool.__class__.pool_size.fset, self._pool, int(num))
|
||||
|
||||
async def _cmd_num_running(self, **_kwargs) -> None:
|
||||
log.debug("%s requests number of running tasks", self._client_class_name)
|
||||
await self._write_function_output(self._pool.__class__.num_running.fget, self._pool)
|
||||
|
||||
async def _cmd_start(self, **kwargs) -> None:
|
||||
num = kwargs[NUM]
|
||||
log.debug("%s requests starting %s %s", self._client_class_name, num, tasks_str(num))
|
||||
await self._write_function_output(self._pool.start, num)
|
||||
|
||||
async def _cmd_stop(self, **kwargs) -> None:
|
||||
num = kwargs[NUM]
|
||||
log.debug("%s requests stopping %s %s", self._client_class_name, num, tasks_str(num))
|
||||
await self._write_function_output(self._pool.stop, num)
|
||||
|
||||
async def _cmd_stop_all(self, **_kwargs) -> None:
|
||||
log.debug("%s requests stopping all tasks", self._client_class_name)
|
||||
await self._write_function_output(self._pool.stop_all)
|
||||
|
||||
async def _cmd_func_name(self, **_kwargs) -> None:
|
||||
log.debug("%s requests pool function name", self._client_class_name)
|
||||
await self._write_function_output(self._pool.__class__.func_name.fget, self._pool)
|
||||
|
||||
async def _execute_command(self, args: Namespace) -> None:
|
||||
args = vars(args)
|
||||
cmd: str = args.pop(constants.CMD, None)
|
||||
if cmd is not None:
|
||||
method = getattr(self, f'_cmd_{cmd.replace("-", "_")}')
|
||||
await method(**args)
|
||||
|
||||
async def _parse_command(self, msg: str) -> None:
|
||||
try:
|
||||
args, argv = self._parser.parse_known_args(msg.split(' '))
|
||||
except ArgumentError as e:
|
||||
self._writer.write(str(e).encode())
|
||||
return
|
||||
except HelpRequested:
|
||||
return
|
||||
if argv:
|
||||
log.debug("%s sent unknown arguments: %s", self._client_class_name, msg)
|
||||
self._writer.write(b"Invalid command!")
|
||||
return
|
||||
await self._execute_command(args)
|
||||
|
||||
async def listen(self) -> None:
|
||||
while self._control_server.is_serving():
|
||||
msg = (await self._reader.read(constants.MSG_BYTES)).decode().strip()
|
||||
if not msg:
|
||||
log.debug("%s disconnected", self._client_class_name)
|
||||
break
|
||||
await self._parse_command(msg)
|
||||
await self._writer.drain()
|
||||
Reference in New Issue
Block a user