Function getDoc

static/js/jquery.form.js:459–491

(frame)

            var SERVER_ABORT = 2;

            function getDoc(frame) {
                /* it looks like contentWindow or contentDocument do not
                 * carry the protocol property in ie8, when running under ssl
                 * frame.document is the only valid response document, since
                 * the protocol is know but not on the other two objects. strange?
                 * "Same origin policy" http://en.wikipedia.org/wiki/Same_origin_policy
                 */

                var doc = null;

                // IE8 cascading access check
                try {
                    if (frame.contentWindow) {
                        doc = frame.contentWindow.document;
                    }
                } catch(err) {
                    // IE8 access denied under ssl & missing protocol
                    log('cannot get iframe.contentWindow document: ' + err);
                }

                if (doc) { // successful getting content
                    return doc;
                }

                try { // simply checking may throw in ie8 under ssl or mismatched protocol
                    doc = frame.contentDocument ? frame.contentDocument : frame.document;
                } catch(err) {
                    // last attempt
                    log('cannot get iframe.contentDocument: ' + err);
                    doc = frame.document;
                }
                return doc;
            }

            // Rails CSRF hack (thanks to Yvan Barthelemy)
            var csrf_token = $('meta[name=csrf-token]').attr('content');