CODEWITHSUNDEEP
javascriptnode.jsxmlhttprequest
Mateusz Zając
Mateusz Zając

Reputation: 326

Javascript xmlhttp get request to nodejs server returns nothing

Before I begin I'd like to tell all of you that I made a lot of searching for solution of this problem on my own.

Here is my nodejs server:

var http = require('http');
http.createServer(function (req, res) {
    console.log("Recived request url " + req.url);
    var sname = req.url.search("name");
    if(sname != -1){
        sname = sname + "name".length + 1;
        var from = sname;
        while(req.url[sname] != '?' && sname<req.url.length){
            sname++;
        }
        var name = req.url.substring(from,sname);
        console.log("Returning parameter of name - " + name);
        res.writeHead(200, {'Content-Type': 'text/plain'});
        res.end(name+'\n');
    }
    else{
        res.writeHead(200, {'Content-Type': 'text/plain'});
        res.end('Error - ask about name\n');
    }

}).listen(1337, '127.0.0.1');
console.log('Server running at http://127.0.0.1:1337/');

It listens on port 1337 and if request url is correct it returns some string.

Here is my javascript code asking nodejs for answer.

function httpGet(theUrl){
    var xmlHttp = null;
    xmlHttp = new XMLHttpRequest();
    xmlHttp.open( "GET", theUrl, true );
    xmlHttp.send( null );
    return xmlHttp.responseText;
}

var url = httpGet("http://127.0.0.1:1337/?name=Mateusz");

setTimeout(function(){
    document.getElementById("actualnewsspace").innerHTML=url;
    var xurl = httpGet("http://127.0.0.1:1337/?"+url);
},5000)

returned xmlHttp.responseText is blank. Why? That's my question.

That's what my nodejs server has to say in this matter

Recived request url /?name=Mateusz
Returning parameter of name - Mateusz
Recived request url /?

If I curl my server it returns mi proper value.

Upvotes: 4

Views: 1308

Answers (1)

Quentin
Quentin

Reputation: 943579

xmlHttp.responseText hasn't been populated when you return it. Ajax is Asynchronous.

See Using XMLHttpRequest and bind an event handler to listen for when the HTTP response has arrived and process the data in that.

Upvotes: 3

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