Ostap Hnatyuk Ostap Hnatyuk - 5 months ago 9
Node.js Question

Node.js server that accepts POST requests

I'm trying to allow javascript to communicate with a Node.js server.

POST request (Javascript)

var http = new XMLHttpRequest();
var params = "text=stuff";
http.open("POST", "http://someurl.net:8080", true);

http.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
http.setRequestHeader("Content-length", params.length);
http.setRequestHeader("Connection", "close");

alert(http.onreadystatechange);
http.onreadystatechange = function() {
if (http.readyState == 4 && http.status == 200) {
alert(http.responseText);
}
}

http.send(params);


Right now the Node.js server code looks like this. Before it was used for GET requests. I'm not sure how to make it work with POST requests.

Server (Node.js)

var server = http.createServer(function (request, response) {
var queryData = url.parse(request.url, true).query;

if (queryData.text) {
convert('engfemale1', queryData.text, response);
response.writeHead(200, {
'Content-Type': 'audio/mp3',
'Content-Disposition': 'attachment; filename="tts.mp3"'
});
}
else {
response.end('No text to convert.');
}
}).listen(8080);


Thanks in advance for your help.

Answer

The following code shows how to read values from an HTML form. As @pimvdb said you need to use the request.on('data'...) to capture the contents of the body.

http = require('http');
fs = require('fs');
server = http.createServer( function(req, res) {

    console.dir(req.param);

    if (req.method == 'POST') {
        console.log("POST");
        var body = '';
        req.on('data', function (data) {
            body += data;
            console.log("Partial body: " + body);
        });
        req.on('end', function () {
            console.log("Body: " + body);
        });
        res.writeHead(200, {'Content-Type': 'text/html'});
        res.end('post received');
    }
    else
    {
        console.log("GET");
        //var html = '<html><body><form method="post" action="http://localhost:3000">Name: <input type="text" name="name" /><input type="submit" value="Submit" /></form></body>';
        var html = fs.readFileSync('index.html');
        res.writeHead(200, {'Content-Type': 'text/html'});
        res.end(html);
    }

});

port = 3000;
host = '127.0.0.1';
server.listen(port, host);
console.log('Listening at http://' + host + ':' + port);

If you use something like Express.js then it can be simplified to something like this since Express takes care of a lot of the HTTP plumbing for you:

var express = require('express');
var fs = require('fs');
var app = express();

app.use(express.bodyParser());

app.get('/', function(req, res){
    console.log('GET /')
    //var html = '<html><body><form method="post" action="http://localhost:3000">Name: <input type="text" name="name" /><input type="submit" value="Submit" /></form></body>';
    var html = fs.readFileSync('index.html');
    res.writeHead(200, {'Content-Type': 'text/html'});
    res.end(html);
});

app.post('/', function(req, res){
    console.log('POST /');
    console.dir(req.body);
    res.writeHead(200, {'Content-Type': 'text/html'});
    res.end('thanks');
});

port = 3000;
app.listen(port);
console.log('Listening at http://localhost:' + port)

In both cases I am reading "index.html" which is a very basic HTML file with the JavaScript that you are using:

<html>
<body>
    <form method="post" action="http://localhost:3000">
        Name: <input type="text" name="name" />
        <input type="submit" value="Submit" />
    </form>

    <script type="text/JavaScript">
        console.log('begin');
        var http = new XMLHttpRequest();
        var params = "text=stuff";
        http.open("POST", "http://localhost:3000", true);

        http.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
        //http.setRequestHeader("Content-length", params.length);
        //http.setRequestHeader("Connection", "close");

        http.onreadystatechange = function() {
            console.log('onreadystatechange');
            if (http.readyState == 4 && http.status == 200) {
                alert(http.responseText);
            }
            else {
                console.log('readyState=' + http.readyState + ', status: ' + http.status);
            }
        }

        console.log('sending...')
        http.send(params);
        console.log('end');

    </script>

</body>
</html>