Update README.md

README.md

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 Go api for Triennale-elettronica-polimi "e-mail us" [section](https://triennale-elettronica-polimi.netlify.app/contact/#e-mail-us) with [friendly captcha](https://friendlycaptcha.com/) protection.
 
-It sends message to a Telegram-bot and it's hosted on [flyio](https://fly.io/), automatically deployed on master changes via [Github Actions](https://github.com/TIT8/go-api/actions/workflows/fly.yml).
+## How it works
+
+1.   It receives the form data submitted via [javascript POST request](https://github.com/valerionew/triennale-elettronica-polimi/blob/master/layouts/shortcodes/contact.html#L58) from the website.
+2.   Check if the data body isn't too big and malformed.
+3.   Check if the captcha submission was successful. If not, send back to the client the captcha error and jump to step 6.
+4.   It sends message to a Telegram BOT which will write to a private channel ([here](https://stackoverflow.com/questions/33858927/how-to-obtain-the-chat-id-of-a-private-telegram-channel) how).
+5.   Check if the communication with the Telegram API was successful.
+6.   Write the result on the HTTP header (200 or 406) and on the responsse to the javascript client.
+7.   The Javascript client will [handle the response](https://github.com/valerionew/triennale-elettronica-polimi/blob/master/layouts/shortcodes/contact.html#L73) and inform the user about the operation (inserting text on HTML).
+
+It's hosted on **[flyio](https://fly.io/)**, automatically deployed on master changes via [Github Actions](https://github.com/TIT8/go-api/actions/workflows/fly.yml). Try it sending a GET request to _https://formapi.fly.dev_.
+
+## Thanks
 
 I would like to express my gratitude to [Marius](https://medium.com/geekculture/how-to-use-go-to-send-telegram-messages-to-your-phone-a819bdf7f35c) for his well-explained blog post, which served as an inspiration for my API.