python-telegram-bot/telegram/utils/helpers.py
2020-10-07 20:30:41 +02:00

435 lines
15 KiB
Python

#!/usr/bin/env python
#
# A library that provides a Python interface to the Telegram Bot API
# Copyright (C) 2015-2020
# 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 helper functions."""
import datetime as dtm # dtm = "DateTime Module"
import re
import signal
import time
from collections import defaultdict
from html import escape
from numbers import Number
import pytz
try:
import ujson as json
except ImportError:
import json # type: ignore[no-redef]
from telegram.utils.types import JSONDict
from typing import Union, Any, Optional, Dict, DefaultDict, Tuple, TYPE_CHECKING
if TYPE_CHECKING:
from telegram import MessageEntity
# From https://stackoverflow.com/questions/2549939/get-signal-names-from-numbers-in-python
_signames = {v: k
for k, v in reversed(sorted(vars(signal).items()))
if k.startswith('SIG') and not k.startswith('SIG_')}
def get_signal_name(signum: int) -> str:
"""Returns the signal name of the given signal number."""
return _signames[signum]
def escape_markdown(text: str, version: int = 1, entity_type: str = None) -> str:
"""
Helper function to escape telegram markup symbols.
Args:
text (:obj:`str`): The text.
version (:obj:`int` | :obj:`str`): Use to specify the version of telegrams Markdown.
Either ``1`` or ``2``. Defaults to ``1``.
entity_type (:obj:`str`, optional): For the entity types ``PRE``, ``CODE`` and the link
part of ``TEXT_LINKS``, only certain characters need to be escaped in ``MarkdownV2``.
See the official API documentation for details. Only valid in combination with
``version=2``, will be ignored else.
"""
if int(version) == 1:
escape_chars = r'_*`['
elif int(version) == 2:
if entity_type == 'pre' or entity_type == 'code':
escape_chars = r'\`'
elif entity_type == 'text_link':
escape_chars = r'\)'
else:
escape_chars = r'_*[]()~`>#+-=|{}.!'
else:
raise ValueError('Markdown version must be either 1 or 2!')
return re.sub('([{}])'.format(re.escape(escape_chars)), r'\\\1', text)
# -------- date/time related helpers --------
def _datetime_to_float_timestamp(dt_obj: dtm.datetime) -> float:
"""
Converts a datetime object to a float timestamp (with sub-second precision).
If the datetime object is timezone-naive, it is assumed to be in UTC.
"""
if dt_obj.tzinfo is None:
dt_obj = dt_obj.replace(tzinfo=dtm.timezone.utc)
return dt_obj.timestamp()
def to_float_timestamp(t: Union[int, float, dtm.timedelta, dtm.datetime, dtm.time],
reference_timestamp: float = None, tzinfo: pytz.BaseTzInfo = None) -> float:
"""
Converts a given time object to a float POSIX timestamp.
Used to convert different time specifications to a common format. The time object
can be relative (i.e. indicate a time increment, or a time of day) or absolute.
Any objects from the :class:`datetime` module that are timezone-naive will be assumed
to be in UTC, if ``bot`` is not passed or ``bot.defaults`` is :obj:`None`.
Args:
t (int | float | datetime.timedelta | datetime.datetime | datetime.time):
Time value to convert. The semantics of this parameter will depend on its type:
* :obj:`int` or :obj:`float` will be interpreted as "seconds from ``reference_t``"
* :obj:`datetime.timedelta` will be interpreted as
"time increment from ``reference_t``"
* :obj:`datetime.datetime` will be interpreted as an absolute date/time value
* :obj:`datetime.time` will be interpreted as a specific time of day
reference_timestamp (float, optional): POSIX timestamp that indicates the absolute time
from which relative calculations are to be performed (e.g. when ``t`` is given as an
:obj:`int`, indicating "seconds from ``reference_t``"). Defaults to now (the time at
which this function is called).
If ``t`` is given as an absolute representation of date & time (i.e. a
``datetime.datetime`` object), ``reference_timestamp`` is not relevant and so its
value should be :obj:`None`. If this is not the case, a ``ValueError`` will be raised.
tzinfo (:obj:`datetime.tzinfo`, optional): If ``t`` is a naive object from the
:class:`datetime` module, it will be interpreted as this timezone. Defaults to
``pytz.utc``.
Returns:
(float | None) The return value depends on the type of argument ``t``. If ``t`` is
given as a time increment (i.e. as a obj:`int`, :obj:`float` or
:obj:`datetime.timedelta`), then the return value will be ``reference_t`` + ``t``.
Else if it is given as an absolute date/time value (i.e. a :obj:`datetime.datetime`
object), the equivalent value as a POSIX timestamp will be returned.
Finally, if it is a time of the day without date (i.e. a :obj:`datetime.time`
object), the return value is the nearest future occurrence of that time of day.
Raises:
TypeError: if `t`'s type is not one of those described above
"""
if reference_timestamp is None:
reference_timestamp = time.time()
elif isinstance(t, dtm.datetime):
raise ValueError('t is an (absolute) datetime while reference_timestamp is not None')
if isinstance(t, dtm.timedelta):
return reference_timestamp + t.total_seconds()
elif isinstance(t, (int, float)):
return reference_timestamp + t
if tzinfo is None:
tzinfo = pytz.utc
if isinstance(t, dtm.time):
reference_dt = dtm.datetime.fromtimestamp(reference_timestamp, tz=t.tzinfo or tzinfo)
reference_date = reference_dt.date()
reference_time = reference_dt.timetz()
aware_datetime = dtm.datetime.combine(reference_date, t)
if aware_datetime.tzinfo is None:
aware_datetime = tzinfo.localize(aware_datetime)
# if the time of day has passed today, use tomorrow
if reference_time > aware_datetime.timetz():
aware_datetime += dtm.timedelta(days=1)
return _datetime_to_float_timestamp(aware_datetime)
elif isinstance(t, dtm.datetime):
if t.tzinfo is None:
t = tzinfo.localize(t)
return _datetime_to_float_timestamp(t)
elif isinstance(t, Number):
return reference_timestamp + t
raise TypeError('Unable to convert {} object to timestamp'.format(type(t).__name__))
def to_timestamp(dt_obj: Union[int, float, dtm.timedelta, dtm.datetime, dtm.time, None],
reference_timestamp: float = None,
tzinfo: pytz.BaseTzInfo = None) -> Optional[int]:
"""
Wrapper over :func:`to_float_timestamp` which returns an integer (the float value truncated
down to the nearest integer).
See the documentation for :func:`to_float_timestamp` for more details.
"""
return (int(to_float_timestamp(dt_obj, reference_timestamp, tzinfo))
if dt_obj is not None else None)
def from_timestamp(unixtime: Optional[int],
tzinfo: dtm.tzinfo = pytz.utc) -> Optional[dtm.datetime]:
"""
Converts an (integer) unix timestamp to a timezone aware datetime object.
:obj:`None`s are left alone (i.e. ``from_timestamp(None)`` is :obj:`None`).
Args:
unixtime (int): Integer POSIX timestamp.
tzinfo (:obj:`datetime.tzinfo`, optional): The timezone, the timestamp is to be converted
to. Defaults to UTC.
Returns:
timezone aware equivalent :obj:`datetime.datetime` value if ``timestamp`` is not
:obj:`None`; else :obj:`None`
"""
if unixtime is None:
return None
if tzinfo is not None:
return dtm.datetime.fromtimestamp(unixtime, tz=tzinfo)
else:
return dtm.datetime.utcfromtimestamp(unixtime)
# -------- end --------
def mention_html(user_id: int, name: str) -> Optional[str]:
"""
Args:
user_id (:obj:`int`) The user's id which you want to mention.
name (:obj:`str`) The name the mention is showing.
Returns:
:obj:`str`: The inline mention for the user as html.
"""
if isinstance(user_id, int):
return u'<a href="tg://user?id={}">{}</a>'.format(user_id, escape(name))
def mention_markdown(user_id: int, name: str, version: int = 1) -> Optional[str]:
"""
Args:
user_id (:obj:`int`) The user's id which you want to mention.
name (:obj:`str`) The name the mention is showing.
version (:obj:`int` | :obj:`str`): Use to specify the version of telegrams Markdown.
Either ``1`` or ``2``. Defaults to ``1``
Returns:
:obj:`str`: The inline mention for the user as markdown.
"""
if isinstance(user_id, int):
return u'[{}](tg://user?id={})'.format(escape_markdown(name, version=version), user_id)
def effective_message_type(entity: 'MessageEntity') -> Optional[str]:
"""
Extracts the type of message as a string identifier from a :class:`telegram.Message` or a
:class:`telegram.Update`.
Args:
entity (:obj:`Update` | :obj:`Message`) The ``update`` or ``message`` to extract from
Returns:
str: One of ``Message.MESSAGE_TYPES``
"""
# Importing on file-level yields cyclic Import Errors
from telegram import Message
from telegram import Update
if isinstance(entity, Message):
message = entity
elif isinstance(entity, Update):
message = entity.effective_message
else:
raise TypeError("entity is not Message or Update (got: {})".format(type(entity)))
for i in Message.MESSAGE_TYPES:
if getattr(message, i, None):
return i
return None
def create_deep_linked_url(bot_username: str, payload: str = None, group: bool = False) -> str:
"""
Creates a deep-linked URL for this ``bot_username`` with the specified ``payload``.
See https://core.telegram.org/bots#deep-linking to learn more.
The ``payload`` may consist of the following characters: ``A-Z, a-z, 0-9, _, -``
Note:
Works well in conjunction with
``CommandHandler("start", callback, filters = Filters.regex('payload'))``
Examples:
``create_deep_linked_url(bot.get_me().username, "some-params")``
Args:
bot_username (:obj:`str`): The username to link to
payload (:obj:`str`, optional): Parameters to encode in the created URL
group (:obj:`bool`, optional): If :obj:`True` the user is prompted to select a group to
add the bot to. If :obj:`False`, opens a one-on-one conversation with the bot.
Defaults to :obj:`False`.
Returns:
:obj:`str`: An URL to start the bot with specific parameters
"""
if bot_username is None or len(bot_username) <= 3:
raise ValueError("You must provide a valid bot_username.")
base_url = 'https://t.me/{}'.format(bot_username)
if not payload:
return base_url
if len(payload) > 64:
raise ValueError("The deep-linking payload must not exceed 64 characters.")
if not re.match(r'^[A-Za-z0-9_-]+$', payload):
raise ValueError("Only the following characters are allowed for deep-linked "
"URLs: A-Z, a-z, 0-9, _ and -")
if group:
key = 'startgroup'
else:
key = 'start'
return '{}?{}={}'.format(
base_url,
key,
payload
)
def encode_conversations_to_json(conversations: Dict[str, Dict[Tuple, Any]]) -> str:
"""Helper method to encode a conversations dict (that uses tuples as keys) to a
JSON-serializable way. Use :attr:`_decode_conversations_from_json` to decode.
Args:
conversations (:obj:`dict`): The conversations dict to transform to JSON.
Returns:
:obj:`str`: The JSON-serialized conversations dict
"""
tmp: Dict[str, JSONDict] = {}
for handler, states in conversations.items():
tmp[handler] = {}
for key, state in states.items():
tmp[handler][json.dumps(key)] = state
return json.dumps(tmp)
def decode_conversations_from_json(json_string: str) -> Dict[str, Dict[Tuple, Any]]:
"""Helper method to decode a conversations dict (that uses tuples as keys) from a
JSON-string created with :attr:`_encode_conversations_to_json`.
Args:
json_string (:obj:`str`): The conversations dict as JSON string.
Returns:
:obj:`dict`: The conversations dict after decoding
"""
tmp = json.loads(json_string)
conversations: Dict[str, Dict[Tuple, Any]] = {}
for handler, states in tmp.items():
conversations[handler] = {}
for key, state in states.items():
conversations[handler][tuple(json.loads(key))] = state
return conversations
def decode_user_chat_data_from_json(data: str) -> DefaultDict[int, Dict[Any, Any]]:
"""Helper method to decode chat or user data (that uses ints as keys) from a
JSON-string.
Args:
data (:obj:`str`): The user/chat_data dict as JSON string.
Returns:
:obj:`dict`: The user/chat_data defaultdict after decoding
"""
tmp: DefaultDict[int, Dict[Any, Any]] = defaultdict(dict)
decoded_data = json.loads(data)
for user, user_data in decoded_data.items():
user = int(user)
tmp[user] = {}
for key, value in user_data.items():
try:
key = int(key)
except ValueError:
pass
tmp[user][key] = value
return tmp
class DefaultValue:
"""Wrapper for immutable default arguments that allows to check, if the default value was set
explicitly. Usage::
DefaultOne = DefaultValue(1)
def f(arg=DefaultOne):
if arg is DefaultOne:
print('`arg` is the default')
arg = arg.value
else:
print('`arg` was set explicitly')
print('`arg` = ' + str(arg))
This yields::
>>> f()
`arg` is the default
`arg` = 1
>>> f(1)
`arg` was set explicitly
`arg` = 1
>>> f(2)
`arg` was set explicitly
`arg` = 2
Also allows to evaluate truthiness::
default = DefaultValue(value)
if default:
...
is equivalent to::
default = DefaultValue(value)
if value:
...
Attributes:
value (:obj:`obj`): The value of the default argument
Args:
value (:obj:`obj`): The value of the default argument
"""
def __init__(self, value: Any = None):
self.value = value
def __bool__(self) -> bool:
return bool(self.value)
DEFAULT_NONE: DefaultValue = DefaultValue(None)
""":class:`DefaultValue`: Default `None`"""