Load and read XML via AJAX Cross-Domain

Question

I have an AJAX Cross-Domain request that receives an XML. After a lot of work, I was able to download the XML but I don’t know if I did it the right way because it never arrives in Success. Follow the requisition code:

function refreshPage() {

$.ajax({ url: 'http://finansite-a.ae.com.br/localiza/xml/localiza.xml',
    crossDomain: true, 
    dataType: 'jsonp',
    success: function (response) {
        $(response).find('li a').each(function () {
            listHref.push($(this).attr('href'));
        });

        var nome_arquivos = new Array();
        var DHTML = (document.getElementById || document.all || document.layers);
        var xmlDocWin;
        var ini_coluna_win;
        function pegarDiv(nome) {
            if (document.getElementById) {
                this.obj = document.getElementById(nome);
            }
            else if (document.all) {
                this.obj = document.all[nome];
            }
            else if (document.layers) {
                this.obj = document.layers[nome];
            }
        }

        function escrever_campo(id, texto) {
            if (!DHTML) return;
            var x = new pegarDiv(id);
            if (x.obj) {
                x.obj.innerHTML = texto;
            }
            return;
        }

        function pegaCor(valor) {
            cor = 'semvar';
            temp = valor.replace(",", ".");
            if (parseFloat(temp) == 0)
                cor = 'semvar';
            else if (parseFloat(temp) > 0)
                cor = 'varpos';
            else if (parseFloat(temp) < 0)
                cor = 'varneg';
            return cor;
        }

    }

});}

When downloading XML, it is shown in the Google Chrome console the following error message speaking XML: Uncaught Syntaxerror: Unexpected token < in row 1 (header).

Answer 1

What happens is that you have determined the data type as JSONP, this means that the result of request that you are doing will return a JSON that will be executed in a callback defined by you, i.e., assuming that the url you are calling returns the following JSON: {"Name": "Foo", "Id" : 1234, "Rank": 7}, in the case of JSONP you should add to the end of the URL that you are making the request ?jsonp=callback, and then the request would take the result JSON and pass as parameter to the function callback as an example: callback({"Name": "Foo", "Id" : 1234, "Rank": 7});

The first and main problem is that your request is not returning a JSON but an XML, and the second problem is that you are not passing any function of callback, thus, when jQuery tries to parse the answer to pass parameter to its callback it cannot, because it tries to parse a JSON but is actually an XML.

I would recommend that you do this with a language of backend instead of trying to use JS.

You have several options of backend to perform this type of processing: in PHP you have the lib CURL in Python you have the urllib2 in Ruby you have the class Net::Httprequest

Just like in other languages you have your respective libraries that make HTTP Requests in addition to libraries to handle XML, which will make it easier for you to parse the answer.