How to loop inside a custom Telegram bot? - telegram-bot

Question

We are trying to make a telegram price bot but running into an issue that could be solved using third party code, however we can't set the bot to send us the updated price every 5 minutes (or more) WITHOUT USING THIRD PARTY SOLUTIONS for security reasons.
How to loop from INSIDE this code, without using another third party Telegram bot?
Here is the code
import telegram
from telegram.ext import Updater
from telegram.ext import CommandHandler
from tracker import get_prices
telegram_bot_token = "mybot"
updater = Updater(token=telegram_bot_token, use_context=True)
dispatcher = updater.dispatcher
def start(update, context):
chat_id = update.effective_chat.id
message = ""
crypto_data = get_prices()
for i in crypto_data:
coin = crypto_data[i]["coin"]
price = crypto_data[i]["price"]
change_day = crypto_data[i]["change_day"]
change_hour = crypto_data[i]["change_hour"]
message += f" {coin}={price:,.5f}$ \nHour Change: {change_hour:.3f}%\nDay Change: {change_day:.3f}%\n\n"
context.bot.send_message(chat_id=chat_id, text=message)
dispatcher.add_handler(CommandHandler("start", start))
updater.start_polling()
Any solution that correctly sends one message at a time without appending to the previous one? Thanks!

Answer 1

There are different ways to do this.
The first would be with a simple time.sleep() in a while loop:
import time
def start(update, context):
chat_id = update.effective_chat.id
while True:
message = ""
crypto_data = get_prices()
for i in crypto_data:
coin = crypto_data[i]["coin"]
price = crypto_data[i]["price"]
change_day = crypto_data[i]["change_day"]
change_hour = crypto_data[i]["change_hour"]
message += f" {coin}={price:,.5f}$ \nHour Change:{change_hour:.3f}%\nDay Change: {change_day:.3f}%\n\n"
context.bot.send_message(chat_id=chat_id, text=message)
time.sleep(300)
Another method might be using a background process scheduler, but you would probably refactor your start function and only schedule the part that creates/sends the message. (The part inside the while loop)
Advanced Python Scheduler (pip install apscheduler) is a fantastic library for this, but it is a third party library, so maybe not appropriate for you. I have used it on many projects however.
EDIT:
Here's an example of scheduling with apscheduler:
from apscheduler.schedulers.background import BackgroundScheduler
scheduler = BackgroundScheduler()
def message_loop(chat_id, bot):
message = ""
crypto_data = get_prices()
for i in crypto_data:
coin = crypto_data[i]["coin"]
price = crypto_data[i]["price"]
change_day = crypto_data[i]["change_day"]
change_hour = crypto_data[i]["change_hour"]
message += f" {coin}={price:,.5f}$ \nHour Change: {change_hour:.3f}%\nDay Change: {change_day:.3f}%\n\n"
bot.send_message(chat_id=chat_id, text=message)
def start(update, context):
chat_id = update.effective_chat.id
bot = context.bot
scheduler.add_job(message_loop, 'interval', minutes=5, args=(chat_id, bot))
scheduler.start()
# You might want to also add a stop function to your bot:
def stop():
scheduler.shutdown()
dispatcher.add_handler(CommandHandler("start", start))
dispatcher.add_handler(CommandHandler("stop", stop))
updater.start_polling()

Answer 2

you should try to add setinterval or a pure millis() function and you will be good to go