Some error occures after send request to the function url - node.js

Question

I set up a one firebase function to send messages to my bot. But when firebase gets request I can see that some error occurred.
FetchError: request to https://api.telegram.org/bot<BOT-TOKEN>/getMe failed, reason: getaddrinfo EAI_AGAIN api.telegram.org:443
at ClientRequest.<anonymous> (/srv/node_modules/node-fetch/lib/index.js:1453:11)
at emitOne (events.js:116:13)
at ClientRequest.emit (events.js:211:7)
at TLSSocket.socketErrorListener (_http_client.js:401:9)
at emitOne (events.js:116:13)
at TLSSocket.emit (events.js:211:7)
at emitErrorNT (internal/streams/destroy.js:66:8)
at _combinedTickCallback (internal/process/next_tick.js:139:11)
at process._tickDomainCallback (internal/process/next_tick.js:219:9)
and
Error: Can't set headers after they are sent.
at validateHeader (_http_outgoing.js:491:11)
at ServerResponse.setHeader (_http_outgoing.js:498:3)
at ServerResponse.header (/worker/node_modules/express/lib/response.js:767:10)
at ServerResponse.contentType (/worker/node_modules/express/lib/response.js:595:15)
at ServerResponse.sendStatus (/worker/node_modules/express/lib/response.js:357:8)
at /srv/index.js:30:13
at <anonymous>
at process._tickDomainCallback (internal/process/next_tick.js:229:7)
But secound one I suppose does not influence on the result.
As a result, I don't get any message to my to Bot.
The next script that i use:
const functions = require('firebase-functions');
const telegraf = require('telegraf');
const axios = require('axios');
const bot = new telegraf('<BOT-TOKEN>')
bot.start((ctx) => ctx.reply('Welcome!'))
bot.help((ctx) => ctx.reply('Send me a sticker'))
bot.on('sticker', (ctx) => ctx.reply('👍'))
bot.hears('hi', (ctx) => ctx.reply('Hey there'))
bot.launch()
exports.helloWorld = functions.https.onRequest((request, res) => {
const token = '<BOT-TOKEN>';
const url = `https://api.telegram.org/bot${token}/sendMessage`;
axios.post(url, {
chat_id: '154866113',
text: "just do it!"
})
.then(function (response) {
console.log(response);
res.send({ status: "O"});
return 'ok';
})
.catch(function (error) {
console.log(error);
res.sendStatus(500);
});
res.send("Hello from Firebase!");
});

Answer 1

The getaddrinfo EAI_AGAIN error means that you need to switch to the "Flame" or "Blaze" pricing plan.
As a matter of fact, the free "Spark" plan "allows outbound network requests only to Google-owned services". See https://firebase.google.com/pricing/ (hover your mouse on the question mark situated after the "Cloud Functions" title)
The telegram API is not a Google-owned service, so you need to switch to the "Flame" or "Blaze" plan.

Answer 2

I'm guessing the answer to the EAI_AGAIN error is due to a malformed URI. Are you sure https://api.telegram.org/bot<BOT-TOKEN>/getMe is the correct URI and is accessible from where ever this script is being run from?
The second error is due to you calling the res.send() method more than once. Express res objects wrap Node's ServerResponse object, and once the connection is closed via write or end, it cannot be sent again. Try removing the res.send("Hello from Firebase!"); section of your code and coming back.