How to only send HTTP response as plain text (HTML)

Question

I need to implement a calculator on my webpage, which will receive some arguments in the url and is supposed to return just the result, nothing else.

Example:

http://example.com/calc/?x=244&y=123&op=plus

I wrote a program using HTML and JavaScript which returns the correct result and prints it on the webpage.

This prints the result. But the client doesn't just receive the result, but the whole html & script. Does anyone know how I can send only the result to the client?

Edit: If this cannot be done with HTMP and JS, how else?

<!DOCTYPE html>
<html>

<body>
  <p id="demo"></p>
  <script>
    function calculate(url) {
    //  ...
    }

    let url = window.location.href;

    document.write(parseInt(calculate(url)));
  </script>
</body>

</html>

Desired result: 367 is returned to the HTTP client

Actual result: < !DOCTYPE html>

.... ...... is returned to the HTTP client

I made you a snippet. Please update it with relevant code, expected and actual result. What is a droplet? — mplungjan, Jan 12 '21 at 12:53
Assuming you want the URL to return 367, it seems you cannot use html and javascript — mplungjan, Jan 12 '21 at 12:57
You could create a [nodejs application](https://marketplace.digitalocean.com/apps/nodejs) — mplungjan, Jan 12 '21 at 13:01
So that's the answer - the server side cannot be written in HTML, only the client side. So I better use php. Thank you a lot for your help. — Dreana, Jan 12 '21 at 18:20

Rajind Pamoda · Answer 1 · 2021-01-12T12:56:00.987

-1

Try the following

<!DOCTYPE html>
<html>
<body>
<p id="demo"></p>
<script>

function calculate (url_string) {
    try {
        var url = new URL(url_string);
        var x = parseInt(url.searchParams.get("x"));
        var y = parseInt(url.searchParams.get("y"));
        switch(url.searchParams.get("op")){
            case "plus": return x + y;
            // add more cases here
        }
    } catch(e){}
}

let url = window.location.href;

document.write(parseInt(calculate(url)));
</script>
</body>
</html>

edited Jan 12 '21 at 12:56

answered Jan 12 '21 at 12:55

Rajind Pamoda

143
2
10

_I wrote a program using HTML and JavaScript which returns the correct result and prints it on the webpage._ so obviously a droplet does not work that way – mplungjan Jan 12 '21 at 12:55

How to only send HTTP response as plain text (HTML)

1 Answers1