Sending images and more with Telegram bot

Hi everyone,

This is a follow-up tutorial on my previous tutorial about Sending messages with Telegram bot. make sure you check that before following this tutorial.

Sending messages with Telegram bot

Rajitha Gunathilake ・ Nov 10 '19 ・ 3 min read

#bots #telegram #http

in the last tutorial, we talked about sending messages, but telegram has a powerful API that allows us to send more than just text messages.
so in this tutorial, we will get to know how to send images with a telegram bot.This procedure is really simple. we need to send a post request to telegram API with our photo as multipart/form-data.

This is similar to what we used previously, the change is now we are using a different route, and sending form-data with our image attached

Using the follwoing API endpoint https://api.telegram.org/bot<token>/sendPhoto?chat_id=<group chat id >

in multipart form data attach an image file with the name photo

and after sending this we can get a response with "ok": true, and if we look at the chat, we can see that the photo is received.

This can also be done programmatically, I will use nodejs to demonstrate in this example.

const fetch = require("node-fetch");
const fs = require("fs");
const FormData = require("form-data");

let readStream = fs.createReadStream("./image.png");

let form = new FormData();
form.append("photo", readStream);

fetch(
  `https://api.telegram.org/bot<token>/sendPhoto?chat_id=-<chat id>`,

  {
    method: "POST",
    body: form,
  }
)
  .then((res) => res.json())
  .then((response) => {
    console.log(response);
  })
  .catch((error) => {
    console.log(error);
  });

we have used node-fetch package to send the HTTP request from nodejs and form-data package to append formdata to the request.

and after running the script we can see that we get "ok": true, just like before.

there are some limits provided by the telegram when using sendPhoto API
"The photo must be at most 10 MB in size. The photo's width and height must not exceed 10000 in total. Width and height ratio must be at most 20".

Telegram API reference sendphoto method

we can use sendAudio just like the last example to send audio files.

const fetch = require("node-fetch");
const fs = require("fs");
const FormData = require("form-data");

let readStream = fs.createReadStream("./audio.mp3");

let form = new FormData();

form.append("audio", readStream);
form.append("title", "audio dev test");// to show as the title in chat

fetch(
  `https://api.telegram.org/bot<token>/sendAudio?chat_id=-<chat id>`,

  {
    method: "POST",
    body: form,
  }
)
  .then((res) => res.json())
  .then((response) => {
    console.log(response);
  })
  .catch((error) => {
    console.log(error);
  });

limits provided by the telegram when using sendAudio API

"Your audio must be in the .MP3 or .M4A format. On success, the sent Message is returned. Bots can currently send audio files of up to 50 MB in size, this limit may be changed in the future."

Telegram API reference sendaudio method

And the list goes on and on for documents, voice messages,animations , videos etc. you can find all the provided methods in the Telegram reference.

Thanks for reading till the end 🙌

share your thoughts in the comments section.