gistfile1.txt

angular.module("xhr", [])
    .factory("xhr", function($window, $q) {
        return function(opts) {
            var deferred = $q.defer(),
                XHR_DONE = 4; // can't use XMLHttpRequest.DONE since some awful libraries overwrite window.XMLHttpRequest

            // defaults
            opts = angular.extend({
                // url: www.google.com,
                // success: function() {},
                // fail: function() {},
                method: "GET",
                async: true,
                data: null
            }, opts);

            opts.headers = angular.extend({
                //'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8'
            }, opts.headers || {});

             // For IE9 support, if available use XDomainRequest instead of XMLHttpRequest.
	        var useXDomainRequest = $window.XDomainRequest && ($window.XMLHttpRequest && new $window.XMLHttpRequest().responseType === undefined),
                xmlhttp;

            function handler() {
                setTimeout(function() { // this timeout fixes a weird bug with xmlhttp not being up-to-date in chrome
                    if (xmlhttp.readyState === XHR_DONE) {
                        if (/^2\d+$/.test(xmlhttp.status)) {
                            opts.success && opts.success(xmlhttp);
                            deferred.resolve(xmlhttp);
                        } else {
                            opts.fail && opts.fail(xmlhttp);
                            deferred.reject(xmlhttp);
                        }
                    }
                });
            }

            if(useXDomainRequest) {
                xmlhttp = new $window.XDomainRequest();
                xmlhttp.onload = handler;
            } else {
                xmlhttp = new $window.XMLHttpRequest();
                xmlhttp.onreadystatechange = handler;
            }

            xmlhttp.open(opts.method, opts.url, opts.async);

            if(opts.timeout && opts.async) {
                xmlhttp.timeout = opts.timeout;
            }

            angular.forEach(opts.headers, function(value, key) {
                xmlhttp.setRequestHeader(key, value);
            });

            xmlhttp.send(opts.data);

            return angular.extend(deferred.promise, {
                xmlhttp: xmlhttp
            });
        }
    });