python-telegram-bot/telegram/request/_baserequest.py
2022-08-03 08:16:48 +02:00

398 lines
17 KiB
Python

#!/usr/bin/env python
#
# A library that provides a Python interface to the Telegram Bot API
# Copyright (C) 2015-2022
# Leandro Toledo de Souza <devs@python-telegram-bot.org>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program 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 Public License for more details.
#
# You should have received a copy of the GNU Lesser Public License
# along with this program. If not, see [http://www.gnu.org/licenses/].
"""This module contains an abstract class to make POST and GET requests."""
import abc
import asyncio
import json
from contextlib import AbstractAsyncContextManager
from http import HTTPStatus
from types import TracebackType
from typing import ClassVar, Optional, Tuple, Type, TypeVar, Union
from telegram._utils.defaultvalue import DEFAULT_NONE as _DEFAULT_NONE
from telegram._utils.types import JSONDict, ODVInput
from telegram._version import __version__ as ptb_ver
from telegram.error import (
BadRequest,
ChatMigrated,
Conflict,
Forbidden,
InvalidToken,
NetworkError,
RetryAfter,
TelegramError,
)
from telegram.request._requestdata import RequestData
RT = TypeVar("RT", bound="BaseRequest")
class BaseRequest(
AbstractAsyncContextManager,
abc.ABC,
):
"""Abstract interface class that allows python-telegram-bot to make requests to the Bot API.
Can be implemented via different asyncio HTTP libraries. An implementation of this class
must implement all abstract methods and properties.
Instances of this class can be used as asyncio context managers, where
.. code:: python
async with request_object:
# code
is roughly equivalent to
.. code:: python
try:
await request_object.initialize()
# code
finally:
await request_object.shutdown()
Tip:
JSON encoding and decoding is done with the standard library's :mod:`json` by default.
To use a custom library for this, you can override :meth:`parse_json_payload` and implement
custom logic to encode the keys of :attr:`telegram.request.RequestData.parameters`.
.. versionadded:: 20.0
"""
__slots__ = ()
USER_AGENT: ClassVar[str] = f"python-telegram-bot v{ptb_ver} (https://python-telegram-bot.org)"
""":obj:`str`: A description that can be used as user agent for requests made to the Bot API.
"""
DEFAULT_NONE: ClassVar = _DEFAULT_NONE
""":class:`object`: A special object that indicates that an argument of a function was not
explicitly passed. Used for the timeout parameters of :meth:`post` and :meth:`do_request`.
Example:
When calling ``request.post(url)``, ``request`` should use the default timeouts set on
initialization. When calling ``request.post(url, connect_timeout=5, read_timeout=None)``,
``request`` should use ``5`` for the connect timeout and :obj:`None` for the read timeout.
Use ``if parameter is (not) BaseRequest.DEFAULT_NONE:`` to check if the parameter was set.
"""
async def __aenter__(self: RT) -> RT:
try:
await self.initialize()
return self
except Exception as exc:
await self.shutdown()
raise exc
async def __aexit__(
self,
exc_type: Optional[Type[BaseException]],
exc_val: Optional[BaseException],
exc_tb: Optional[TracebackType],
) -> None:
# Make sure not to return `True` so that exceptions are not suppressed
# https://docs.python.org/3/reference/datamodel.html?#object.__aexit__
await self.shutdown()
@abc.abstractmethod
async def initialize(self) -> None:
"""Initialize resources used by this class. Must be implemented by a subclass."""
@abc.abstractmethod
async def shutdown(self) -> None:
"""Stop & clear resources used by this class. Must be implemented by a subclass."""
async def post(
self,
url: str,
request_data: RequestData = None,
read_timeout: ODVInput[float] = DEFAULT_NONE,
write_timeout: ODVInput[float] = DEFAULT_NONE,
connect_timeout: ODVInput[float] = DEFAULT_NONE,
pool_timeout: ODVInput[float] = DEFAULT_NONE,
) -> Union[JSONDict, bool]:
"""Makes a request to the Bot API handles the return code and parses the answer.
Warning:
This method will be called by the methods of :class:`telegram.Bot` and should *not* be
called manually.
Args:
url (:obj:`str`): The URL to request.
request_data (:class:`telegram.request.RequestData`, optional): An object containing
information about parameters and files to upload for the request.
read_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the maximum
amount of time (in seconds) to wait for a response from Telegram's server instead
of the time specified during creating of this object. Defaults to
:attr:`DEFAULT_NONE`.
write_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the maximum
amount of time (in seconds) to wait for a write operation to complete (in terms of
a network socket; i.e. POSTing a request or uploading a file) instead of the time
specified during creating of this object. Defaults to :attr:`DEFAULT_NONE`.
connect_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the
maximum amount of time (in seconds) to wait for a connection attempt to a server
to succeed instead of the time specified during creating of this object. Defaults
to :attr:`DEFAULT_NONE`.
pool_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the maximum
amount of time (in seconds) to wait for a connection to become available instead
of the time specified during creating of this object. Defaults to
:attr:`DEFAULT_NONE`.
Returns:
Dict[:obj:`str`, ...]: The JSON response of the Bot API.
"""
result = await self._request_wrapper(
url=url,
method="POST",
request_data=request_data,
read_timeout=read_timeout,
write_timeout=write_timeout,
connect_timeout=connect_timeout,
pool_timeout=pool_timeout,
)
json_data = self.parse_json_payload(result)
# For successful requests, the results are in the 'result' entry
# see https://core.telegram.org/bots/api#making-requests
return json_data["result"]
async def retrieve(
self,
url: str,
read_timeout: ODVInput[float] = DEFAULT_NONE,
write_timeout: ODVInput[float] = DEFAULT_NONE,
connect_timeout: ODVInput[float] = DEFAULT_NONE,
pool_timeout: ODVInput[float] = DEFAULT_NONE,
) -> bytes:
"""Retrieve the contents of a file by its URL.
Warning:
This method will be called by the methods of :class:`telegram.Bot` and should *not* be
called manually.
Args:
url (:obj:`str`): The web location we want to retrieve.
read_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the maximum
amount of time (in seconds) to wait for a response from Telegram's server instead
of the time specified during creating of this object. Defaults to
:attr:`DEFAULT_NONE`.
write_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the maximum
amount of time (in seconds) to wait for a write operation to complete (in terms of
a network socket; i.e. POSTing a request or uploading a file) instead of the time
specified during creating of this object. Defaults to :attr:`DEFAULT_NONE`.
connect_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the
maximum amount of time (in seconds) to wait for a connection attempt to a server
to succeed instead of the time specified during creating of this object. Defaults
to :attr:`DEFAULT_NONE`.
pool_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the maximum
amount of time (in seconds) to wait for a connection to become available instead
of the time specified during creating of this object. Defaults to
:attr:`DEFAULT_NONE`.
Returns:
:obj:`bytes`: The files contents.
"""
return await self._request_wrapper(
url=url,
method="GET",
read_timeout=read_timeout,
write_timeout=write_timeout,
connect_timeout=connect_timeout,
pool_timeout=pool_timeout,
)
async def _request_wrapper(
self,
url: str,
method: str,
request_data: RequestData = None,
read_timeout: ODVInput[float] = DEFAULT_NONE,
write_timeout: ODVInput[float] = DEFAULT_NONE,
connect_timeout: ODVInput[float] = DEFAULT_NONE,
pool_timeout: ODVInput[float] = DEFAULT_NONE,
) -> bytes:
"""Wraps the real implementation request method.
Performs the following tasks:
* Handle the various HTTP response codes.
* Parse the Telegram server response.
Args:
url (:obj:`str`): The URL to request.
method (:obj:`str`): HTTP method (i.e. 'POST', 'GET', etc.).
request_data (:class:`telegram.request.RequestData`, optional): An object containing
information about parameters and files to upload for the request.
read_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the maximum
amount of time (in seconds) to wait for a response from Telegram's server instead
of the time specified during creating of this object. Defaults to
:attr:`DEFAULT_NONE`.
write_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the maximum
amount of time (in seconds) to wait for a write operation to complete (in terms of
a network socket; i.e. POSTing a request or uploading a file) instead of the time
specified during creating of this object. Defaults to :attr:`DEFAULT_NONE`.
connect_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the
maximum amount of time (in seconds) to wait for a connection attempt to a server
to succeed instead of the time specified during creating of this object. Defaults
to :attr:`DEFAULT_NONE`.
pool_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the maximum
amount of time (in seconds) to wait for a connection to become available instead
of the time specified during creating of this object. Defaults to
:attr:`DEFAULT_NONE`.
Returns:
bytes: The payload part of the HTTP server response.
Raises:
TelegramError
"""
# TGs response also has the fields 'ok' and 'error_code'.
# However, we rather rely on the HTTP status code for now.
try:
code, payload = await self.do_request(
url=url,
method=method,
request_data=request_data,
read_timeout=read_timeout,
write_timeout=write_timeout,
connect_timeout=connect_timeout,
pool_timeout=pool_timeout,
)
except asyncio.CancelledError as exc:
# TODO: in py3.8+, CancelledError is a subclass of BaseException, so we can drop this
# clause when we drop py3.7
raise exc
except TelegramError as exc:
raise exc
except Exception as exc:
raise NetworkError(f"Unknown error in HTTP implementation: {repr(exc)}") from exc
if HTTPStatus.OK <= code <= 299:
# 200-299 range are HTTP success statuses
return payload
response_data = self.parse_json_payload(payload)
description = response_data.get("description")
if description:
message = description
else:
message = "Unknown HTTPError"
# In some special cases, we can raise more informative exceptions:
# see https://core.telegram.org/bots/api#responseparameters and
# https://core.telegram.org/bots/api#making-requests
parameters = response_data.get("parameters")
if parameters:
migrate_to_chat_id = parameters.get("migrate_to_chat_id")
if migrate_to_chat_id:
raise ChatMigrated(migrate_to_chat_id)
retry_after = parameters.get("retry_after")
if retry_after:
raise RetryAfter(retry_after)
message += f"\nThe server response contained unknown parameters: {parameters}"
if code == HTTPStatus.FORBIDDEN: # 403
raise Forbidden(message)
if code in (HTTPStatus.NOT_FOUND, HTTPStatus.UNAUTHORIZED): # 404 and 401
# TG returns 404 Not found for
# 1) malformed tokens
# 2) correct tokens but non-existing method, e.g. api.tg.org/botTOKEN/unkonwnMethod
# We can basically rule out 2) since we don't let users make requests manually
# TG returns 401 Unauthorized for correctly formatted tokens that are not valid
raise InvalidToken(message)
if code == HTTPStatus.BAD_REQUEST: # 400
raise BadRequest(message)
if code == HTTPStatus.CONFLICT: # 409
raise Conflict(message)
if code == HTTPStatus.BAD_GATEWAY: # 502
raise NetworkError(description or "Bad Gateway")
raise NetworkError(f"{message} ({code})")
@staticmethod
def parse_json_payload(payload: bytes) -> JSONDict:
"""Parse the JSON returned from Telegram.
Tip:
By default, this method uses the standard library's :func:`json.loads` and
``errors="replace"`` in :meth:`bytes.decode`.
You can override it to customize either of these behaviors.
Args:
payload (:obj:`bytes`): The UTF-8 encoded JSON payload as returned by Telegram.
Returns:
dict: A JSON parsed as Python dict with results.
Raises:
TelegramError: If loading the JSON data failed
"""
decoded_s = payload.decode("utf-8", "replace")
try:
return json.loads(decoded_s)
except ValueError as exc:
raise TelegramError("Invalid server response") from exc
@abc.abstractmethod
async def do_request(
self,
url: str,
method: str,
request_data: RequestData = None,
read_timeout: ODVInput[float] = DEFAULT_NONE,
write_timeout: ODVInput[float] = DEFAULT_NONE,
connect_timeout: ODVInput[float] = DEFAULT_NONE,
pool_timeout: ODVInput[float] = DEFAULT_NONE,
) -> Tuple[int, bytes]:
"""Makes a request to the Bot API. Must be implemented by a subclass.
Warning:
This method will be called by :meth:`post` and :meth:`retrieve`. It should *not* be
called manually.
Args:
url (:obj:`str`): The URL to request.
method (:obj:`str`): HTTP method (i.e. ``'POST'``, ``'GET'``, etc.).
request_data (:class:`telegram.request.RequestData`, optional): An object containing
information about parameters and files to upload for the request.
read_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the maximum
amount of time (in seconds) to wait for a response from Telegram's server instead
of the time specified during creating of this object. Defaults to
:attr:`DEFAULT_NONE`.
write_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the maximum
amount of time (in seconds) to wait for a write operation to complete (in terms of
a network socket; i.e. POSTing a request or uploading a file) instead of the time
specified during creating of this object. Defaults to :attr:`DEFAULT_NONE`.
connect_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the
maximum amount of time (in seconds) to wait for a connection attempt to a server
to succeed instead of the time specified during creating of this object. Defaults
to :attr:`DEFAULT_NONE`.
pool_timeout (:obj:`float` | :obj:`None`, optional): If passed, specifies the maximum
amount of time (in seconds) to wait for a connection to become available instead
of the time specified during creating of this object. Defaults to
:attr:`DEFAULT_NONE`.
Returns:
Tuple[:obj:`int`, :obj:`bytes`]: The HTTP return code & the payload part of the server
response.
"""