Enable 'Access-Control-Allow-Origin' in jQuery [xml]

The Access-Control-Allow-Origin can only be enabled on the server. The purpose of this rule is for the browser not to be able to access content that the server does not want to be accessed when the request domain is not the same as that of the server.

O should be added to the .xml server (which is not possible because it is the Yahoo server, only they have this control) and no on your page, if it could be done directly this by the client would be a security flaw and would not even need CORs control.

However it is possible to create a web-proxy with curl to work around this, an example:

Create a file named moedas.php and add this:

<?php

$url = 'https://finance.yahoo.com/webservice/v1/symbols/allcurrencies/quote';

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);

//Define um User-agent
curl_setopt($ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (Windows NT 5.1; rv:21.0) Gecko/20100101 Firefox/21.0');

curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 30);
curl_setopt($ch, CURLOPT_TIMEOUT, 30);

//Retorna a resposta
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

//Resposta
$data = curl_exec($ch);

if($data === false) {
    echo 'Erro ao executar o CURL: ' . curl_error($ch);
} else {
    $httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);

    if ($httpcode !== 200) {
        header('X-PHP-Response-Code: ' . $httpcode, true, $httpcode);
        die('Erro ao requisitar o servidor');
    }
}

header('Content-Type: text/xml');

//Exibe dados
echo $data;

Then in Ajax call:

$(document).ready(function(){
    $.ajax({
        url: 'moedas.php',
        success: function(response){
            console.log(response);
        },
        error: function(err){
            console.log(err);
        }
    });
});

  

Note: If you are using PHP 5.4+ you can switch header('X-PHP-Response-Code: ' . $httpcode, true, $httpcode); to http_response_code($httpcode);

If you create a php file and do:

<?php
    call_user_func($_POST['funcao']);
    function cotacao(){
        /* Faço load do arquivo xml */
        $xml = simplexml_load_file('https://finance.yahoo.com/webservice/v1/symbols/allcurrencies/quote');
        /* Retono uma String xml bem formada */
    echo $xml->asXML();
    }
?>

And call this document:

$(document).ready(function(){
    $.ajax({
        url: 'documento.php',
        dataType: 'text/xml',
        type: 'post',
        success: function(response){
            console.log(response);
        }
    });
});

It works great, I wanted to do this direct call through jQuery, but for what I understand it has no way.