Heroku deploy chat bot - heroku

Question

so, my code works both locally and docker image but, when I deploy to heroku it seems to work on first 1 minute and then app crashes, there is heroku logs, after crashing so what can be problems? any thought? thank you
there is my code
const { default: axios } = require('axios')
const telegramBot = require('node-telegram-bot-api')
const express = require('express')
const dotenv = require('dotenv').config()
const links = `
GitLab
Linkdin
Personal
`
const bot = new telegramBot(process.env.TOKEN, { polling: true })
const aboutText = 'Hello, I am learning NODE JS!'
const app = express()
bot.on('message', (message) => {
const id = message.chat.id
if (message.text === '/start' || message.text === '/help') {
bot.sendMessage(message.chat.id, 'avalable commands', {
reply_markup: {
keyboard: [['/about', '/links']],
resize_keyboard: true,
one_time_keyboard: true,
force_reply: true,
},
})
} else if (message.text === '/about') {
bot.sendMessage(id, aboutText)
} else if (message.text === '/links') {
bot.sendMessage(id, links, { parse_mode: 'HTML' })
} else {
bot.sendMessage(
message.chat.id,
'no such command! there are avalable commands',
{
reply_markup: {
keyboard: [['/about', '/links']],
resize_keyboard: true,
one_time_keyboard: true,
force_reply: true,
},
}
)
}
})
dockerfile:
FROM node:16-alpine
WORKDIR /app
COPY package*.json ./
RUN npm install --production
COPY ./app.js .
ENV port=8080
ENV TOKEN=21*****:AAEF******************fKiQ
EXPOSE 8080
CMD [ "node", "app.js" ]

Answer 1

Your app fails to bind to the port assigned by Heroku: you cannot set the port yourself (ie 8080) but instead bind to the port defined by the $PORT env variable.
See Why is my Node.js app crashing with an R10 error? to understand the details.
In your specific case if you run the Bot in polling mode (i.e. pulling the changes) you can instead use a worker node instead of a web: doing this you don't need to bind to the port as your application does not require to process incoming HTTP requests.