warning to install optional dependencies

docs/source/examples.rst

@@ -40,6 +40,7 @@ up a job to send a message to that user after 30 seconds. The user can
 also cancel the timer by sending ``/unset``. To learn more about the
 ``JobQueue``, read `this wiki
 article <https://github.com/python-telegram-bot/python-telegram-bot/wiki/Extensions-%E2%80%93-JobQueue>`__.
+Note: To use ``JobQueue``, you must install PTB via ``pip install python-telegram-bot[job-queue]``
 
 :any:`examples.conversationbot`
 -------------------------------
@@ -115,6 +116,7 @@ Don’t forget to enable and configure payments with
 `@BotFather <https://telegram.me/BotFather>`_. Check out this
 `guide <https://github.com/python-telegram-bot/python-telegram-bot/wiki/Telegram-Passport>`__
 on Telegram passports in PTB.
+Note: To use Telegram Passport, you must install PTB via ``pip install python-telegram-bot[passport]``
 
 :any:`examples.paymentbot`
 --------------------------
@@ -162,6 +164,7 @@ combination with ``telegram.ext.Application``.
 
 This example showcases how PTBs “arbitrary callback data” feature can be
 used.
+Note: To use arbitrary callback data, you must install PTB via ``pip install python-telegram-bot[callback-data]``
 
 Pure API
 --------

examples/arbitrarycallbackdatabot.py

@@ -6,6 +6,10 @@
 
 For detailed info on arbitrary callback data, see the wiki page at
 https://github.com/python-telegram-bot/python-telegram-bot/wiki/Arbitrary-callback_data
+
+Note:
+To use arbitrary callback data, you must install PTB via
+`pip install python-telegram-bot[callback-data]`
 """
 import logging
 from typing import List, Tuple, cast

examples/passportbot.py

@@ -10,6 +10,9 @@
 See https://github.com/python-telegram-bot/python-telegram-bot/wiki/Telegram-Passport
  for how to use Telegram Passport properly with python-telegram-bot.
 
+Note:
+To use Telegram Passport, you must install PTB via
+`pip install python-telegram-bot[passport]`
 """
 import logging
 from pathlib import Path

examples/timerbot.py

@@ -16,6 +16,10 @@
 Basic Alarm Bot example, sends a message after a set time.
 Press Ctrl-C on the command line or send a signal to the process to stop the
 bot.
+
+Note:
+To use arbitrary callback data, you must install ptb via
+`pip install python-telegram-bot[callback-data]`
 """
 
 import logging

telegram/ext/_application.py

@@ -64,7 +64,7 @@
 
 if TYPE_CHECKING:
     from telegram import Message
-    from telegram.ext import ConversationHandler
+    from telegram.ext import ConversationHandler, JobQueue
     from telegram.ext._applicationbuilder import InitApplicationBuilder
     from telegram.ext._jobqueue import Job
 
@@ -218,6 +218,7 @@ class Application(Generic[BT, CCT, UD, CD, BD, JQ], AbstractAsyncContextManager)
         "_concurrent_updates_sem",
         "_conversation_handler_conversations",
         "_initialized",
+        "_job_queue",
         "_running",
         "_user_data",
         "_user_ids_to_be_deleted_in_persistence",
@@ -228,7 +229,6 @@ class Application(Generic[BT, CCT, UD, CD, BD, JQ], AbstractAsyncContextManager)
         "context_types",
         "error_handlers",
         "handlers",
-        "job_queue",
         "persistence",
         "post_init",
         "post_shutdown",
@@ -264,7 +264,6 @@ def __init__(
 
         self.bot = bot
         self.update_queue = update_queue
-        self.job_queue = job_queue
         self.context_types = context_types
         self.updater = updater
         self.handlers: Dict[int, List[BaseHandler]] = {}
@@ -306,6 +305,7 @@ def __init__(
         # A number of low-level helpers for the internal logic
         self._initialized = False
         self._running = False
+        self._job_queue = job_queue
         self.__update_fetcher_task: Optional[asyncio.Task] = None
         self.__update_persistence_task: Optional[asyncio.Task] = None
         self.__update_persistence_event = asyncio.Event()
@@ -337,6 +337,22 @@ def concurrent_updates(self) -> int:
         """
         return self._concurrent_updates
 
+    @property
+    def job_queue(self) -> Optional["JobQueue"]:
+        """
+        :class:`telegram.ext.JobQueue`: The :class:`JobQueue` used by the
+            :class:`telegram.ext.Application`.
+
+        .. seealso:: `Job Queue <https://github.com/python-telegram-bot/
+            python-telegram-bot/wiki/Extensions-%E2%80%93-JobQueue>`_
+        """
+        if self._job_queue is None:
+            warn(
+                "No `JobQueue` set up. To use `JobQueue`, you must install PTB via "
+                "`pip install python-telegram-bot[job_queue]`."
+            )
+        return self._job_queue
+
     async def initialize(self) -> None:
         """Initializes the Application by initializing:
 
@@ -511,8 +527,8 @@ async def start(self) -> None:
                 )
                 _logger.debug("Loop for updating persistence started")
 
-            if self.job_queue:
-                await self.job_queue.start()  # type: ignore[union-attr]
+            if self._job_queue:
+                await self._job_queue.start()  # type: ignore[union-attr]
                 _logger.debug("JobQueue started")
 
             self.__update_fetcher_task = asyncio.create_task(
@@ -561,9 +577,9 @@ async def stop(self) -> None:
             await self.__update_fetcher_task
         _logger.debug("Application stopped fetching of updates.")
 
-        if self.job_queue:
+        if self._job_queue:
             _logger.debug("Waiting for running jobs to finish")
-            await self.job_queue.stop(wait=True)  # type: ignore[union-attr]
+            await self._job_queue.stop(wait=True)  # type: ignore[union-attr]
             _logger.debug("JobQueue stopped")
 
         _logger.debug("Waiting for `create_task` calls to be processed")

telegram/ext/_callbackcontext.py

@@ -21,6 +21,7 @@
 
 from telegram._callbackquery import CallbackQuery
 from telegram._update import Update
+from telegram._utils.warnings import warn
 from telegram.ext._extbot import ExtBot
 from telegram.ext._utils.types import BD, BT, CD, UD
 
@@ -389,6 +390,11 @@ def job_queue(self) -> Optional["JobQueue"]:
         .. seealso:: `Job Queue <https://github.com/python-telegram-bot/
             python-telegram-bot/wiki/Extensions-%E2%80%93-JobQueue>`_
         """
+        if self._application.job_queue is None:
+            warn(
+                "No `JobQueue` set up. To use `JobQueue`, you must install PTB via "
+                "`pip install python-telegram-bot[job_queue]`."
+            )
         return self._application.job_queue
 
     @property

telegram/ext/_conversationhandler.py

@@ -675,12 +675,15 @@ def _schedule_job(
 
         try:
             # both job_queue & conversation_timeout are checked before calling _schedule_job
-            j_queue = application.job_queue
-            self.timeout_jobs[conversation_key] = j_queue.run_once(
-                self._trigger_timeout,
-                self.conversation_timeout,  # type: ignore[arg-type]
-                data=_ConversationTimeoutContext(conversation_key, update, application, context),
-            )
+            if application.job_queue:
+                j_queue = application.job_queue
+                self.timeout_jobs[conversation_key] = j_queue.run_once(
+                    self._trigger_timeout,
+                    self.conversation_timeout,  # type: ignore[arg-type]
+                    data=_ConversationTimeoutContext(
+                        conversation_key, update, application, context
+                    ),
+                )
         except Exception as exc:
             _logger.exception("Failed to schedule timeout.", exc_info=exc)