How does one send a string which is a value from an HTML tag to a NodeJS server?

Question

I understand I could do that with <form action=/serverfile.js method='post'>, but:

(1) How does one do it with Ajax/Fetch API since they need you to send through a file, like a txt file? I'm only trying to send a string.

(2) How would one do it with <form action=/serverfile.js method='post'> too, what would need to be set up on the server end to collect the incoming data?

The answers I have seen use expressjs. I don't want to use expressjs. Is it impossible to do this with vanilla NodeJS?

One way I found to do this with vanilla NodeJS is like so:

HTML

<form action="/nodedemo_trial" method="post">
<label> Username </label> <br/> <br/>
<input type="text" style="width:200px; font-size:1.5rem" id="username"> <br/> <br/>
<label> Password </label> <br/> <br/>
<input type="text" style="width:200px; font-size:1.5rem" id="password"> <br/> <br/>
<input type="submit" value="Log In" style="width:120px; font-size:1.5rem;" > <br/> <br/>
<input type="submit" value="Sign Up" style="width:120px; font-size:1.5rem;" > <br/> <br/>
</form>

NodeJS:

var http = require('http');
var form = require('fs').readFileSync('homepage.html');
http.createServer(function (request, response) {
if (request.method === "GET") {
response.writeHead(200, {'Content-Type': 'text/html'});
response.end(form);
}


if (request.method === "POST") {
var postData = '';
request.on('data', function (chunk) {
postData += chunk;
}).on('end', function() {
console.log('User Posted:\n' + postData);
response.end('You Posted:\n' + postData);
});
}

}).listen(1000);

When I do this though, the inputed text doesn't get posted, only "You Posted:". And how would one do that with an HTML page with multiple post requests, if the way to intercept incoming data is request.method === "POST"?

Edit: Used querystring. Still doesn't work.

var http = require('http');
var qs = require('querystring');

var form = require('fs').readFileSync('homepage.html');

http.createServer(function (request, response) {
    
if (request.method === "GET") {
response.writeHead(200, {'Content-Type': 'text/html'});
response.end(form);
}


if (request.method === "POST") {
var postData = '';
request.on('data', function (chunk) {
postData += chunk;
}).on('end', function() {
var post = qs.stringify(postData);
console.log('User Posted:\n' + post);
response.end('You Posted:\n' + post);
});
}

}).listen(1000);

Not async either:

var http = require('http');
var fs = require('fs');
var qs = require('querystring');


http.createServer(function (req, res) {

  fs.readFile('homepage.html', function(err, data) {
    res.writeHead(200, {'Content-Type': 'text/html'});
    res.write(data);


if (req.method == 'POST') {

        var body = '';

        req.on('data', function (data) {
            body += data;
            if (body.length > 1e6)
                req.connection.destroy();
        }).on('end', function () {
            var post = qs.stringify(body);
            console.log(post);
           //res.end(post);
        });
    } 
    return res.end();
  });
}).listen(8082);

"*How does one do it with Ajax/Fetch API since they need you to send through a file, like a txt file?*" Can you share the source upon which you're basing your claim that AJAX methodologies or the Fetch API support *only* the sending of arbitrary files and not string data? This claim does not align with the publicly-available documentation I have ever reviewed personally. You seem to be fundamentally misunderstanding what these facilities can support in actuality, and I feel it may be helpful to assist you in pointing out where your misunderstanding may be coming from. — esqew, May 30 '22 at 22:52

score -1 · Accepted Answer · answered Jun 02 '22 at 00:23

-1

The top answer here does work.

Apparently, you need to intercept the data with querystring.parse(postData) to convert it into an object. Converting it into a string via either querystring.stringify(postData) or String(postData)/postData.toString doesn't work. Have no idea why not.

answered Jun 02 '22 at 00:23

0xd6438c

1
3

If another thread on Stack Overflow answers the question, flag/vote to mark the question as a duplicate of that thread so the system can mark it as such and make it extremely obvious to future visitors that the answers they're looking for may reside there. – esqew Jun 02 '22 at 03:49
Pls format the posts correctly. It just makes everyone especially reviewers’ lives easy. You can find more information [here](https://stackoverflow.com/help/formatting). – Archit Gargi Jun 02 '22 at 13:22

How does one send a string which is a value from an HTML tag to a NodeJS server?

1 Answers1