Introduction
The extension class telegram.ext.JobQueue
allows you to perform tasks with a delay or even periodically, at a set interval. Among many other things, you can use it to send regular updates to your subscribers.
When working with JobQueue
, please keep in mind:
- PTBs
JobQueue
provides an easy to use and ready to use way of scheduling tasks in a way that ties in with the PTB architecture - Managing scheduling logic is not the main intend of PTB and hence as of v13 a third party library is used
- If you need highly customized scheduling thingies, you can use advanced features of the third party library
- We can't guarantee that the backend will stay the same forever. For example, if the third party library is discontinued, we will have to look for alternatives.
Example
In addition to the tutorial below, there is also the timerbot.py
example at the examples directory.
Usage
Warning
Since v20, you must install PTB with the optional requirement
job-queue
, i.e.pip install python-telegram-bot[job-queue]
The JobQueue
class is tightly integrated with other telegram.ext
classes.
To use the JobQueue
, you don't have to do much. When you build the Application
, it will create a JobQueue
for you:
from telegram.ext import Application
application = Application.builder().token('TOKEN').build()
job_queue = application.job_queue
Just know that unless you have a good reason to do so, you should not instantiate JobQueue
yourself.
Tasks in the job queue are encapsulated by the Job
class. It takes a callback function as a parameter, which will be executed when the time comes. This callback function always takes exactly one parameter: context
, a telegram.ext.CallbackContext
. Like in the case of handler callbacks used by the Application
, through this object you can access
context.bot
, theApplication
'stelegram.Bot
instancecontext.job_queue
, the same object asapplication.job_queue
above- and for this particular case you can also access
context.job
, which is theJob
instance of the task that triggered the callback (more on that later).
You can use the following methods to create jobs with different frequency and time: job_queue.run_once
, job_queue.run_repeating
, job_queue.run_daily
and job_queue.run_monthly
. (As before, you do not usually need to instantiate the Job
class directly.)
Tutorial
Add your first job to the queue by defining a callback function and adding it to the job queue. For this tutorial, you can replace '@examplechannel'
with a channel where your bot is an admin, or by your user id (use @userinfobot to find out your user id):
from telegram.ext import ContextTypes, Application
async def callback_minute(context: ContextTypes.DEFAULT_TYPE):
await context.bot.send_message(chat_id='@examplechannel', text='One message every minute')
application = Application.builder().token('TOKEN').build()
job_queue = application.job_queue
job_minute = job_queue.run_repeating(callback_minute, interval=60, first=10)
application.run_polling()
The callback_minute
function will be executed every 60.0
seconds, the first time being after 10 seconds (because of first=10
). The interval
and first
parameters are in seconds if they are int
or float
. They can also be datetime
objects. See the docs for detailed explanation.
The return value of these functions are the Job
objects being created. You don't need to store the result of run_repeating
(which is the newly instantiated Job
) if you don't need it; we will make use of it later in this tutorial.
You can also add a job that will be executed only once, with a delay:
from telegram.ext import ContextTypes, Application
async def callback_30(context: ContextTypes.DEFAULT_TYPE):
await context.bot.send_message(chat_id='@examplechannel', text='A single message with 30s delay')
application = Application.builder().token('TOKEN').build()
job_queue = application.job_queue
job_queue.run_once(callback_30, 30)
application.run_polling()
In thirty seconds, you should receive the message from callback_30
.
If you are tired of receiving a message every minute, you can temporarily disable a job or even completely remove it from the queue:
job_minute.enabled = False # Temporarily disable this job
job_minute.schedule_removal() # Remove this job completely
Caution
schedule_removal
does not immediately remove the job from the queue. Instead, it is marked for removal and will be removed as soon as its current interval is over (it will not run again after being marked for removal).
You might want to add jobs in response to certain user input, and there is a convenient way to do that. The context
argument of your Handler
callbacks has the JobQueue
attached as context.job_queue
ready to be used. Another feature you can use here are the data
, chat_id
or user_id
keyword arguments of Job
. You can pass any object as a data
parameter when you launch a Job
and retrieve it at a later stage as long as the Job
exists. The chat_id
/user_id
parameter allows for an easy way to let the Job
know which chat we're talking about. This way, we can access context.chat_data
/context.user_data
in the job's callback
. Let's see how it looks in code:
from telegram import Update
from telegram.ext import CommandHandler, Application, ContextTypes
async def callback_alarm(context: ContextTypes.DEFAULT_TYPE):
# Beep the person who called this alarm:
await context.bot.send_message(chat_id=context.job.chat_id, text=f'BEEP {context.job.data}!')
async def callback_timer(update: Update, context: ContextTypes.DEFAULT_TYPE):
chat_id = update.message.chat_id
name = update.effective_chat.full_name
await context.bot.send_message(chat_id=chat_id, text='Setting a timer for 1 minute!')
# Set the alarm:
context.job_queue.run_once(callback_alarm, 60, data=name, chat_id=chat_id)
application = Application.builder().token('TOKEN').build()
timer_handler = CommandHandler('timer', callback_timer)
application.add_handler(timer_handler)
application.run_polling()
By placing the chat_id
in the Job
object, the callback function knows where it should send the message.
All good things must come to an end, so when you stop the Application, the related job queue will be stopped as well.
Persistent Job Queues
PTBs Persistence Setup currently does not support serialization of jobs.
However, the current backend of the JobQueue
, namely the APScheduler
library has a mechanism for that, which you can leverage.
Check out e.g. ptbcontrib/ptb_jobstores for an example implementation.
Must read
Concepts & Important Elements
- Architecture Overview
- Builder Pattern for
Application
- Types of Handlers
- Working with Files and Media
- Exceptions, Warnings and Logging
- Concurrency in PTB
Notable Features
- Advanced Filters
- Storing data
- Making your bot persistent
- Adding Defaults
- Job Queue
- Arbitrary
callback_data
- Avoiding flood limits
- Webhooks
- Bot API Forward Compatiblity
Code Resources
- Frequently requested design patterns
- Code snippets
- Performance Optimizations
- Telegram Passport
- Bots built with PTB
- Automated Bot Tests
Examples explained
Networking
Other resources
- Where to host Telegram Bots
- How to host your bot
- Local API Server
- Type Checking with PTB
- Press
- Notes on GAE
- Related Projects
- Emoji
Transition Guides
Administration
- Wiki of
python-telegram-bot
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