lepu-test-platform-web/node_modules/sockjs-client/lib/transport/sender/jsonp.js

100 lines
2.4 KiB
JavaScript

'use strict';
var random = require('../../utils/random')
, urlUtils = require('../../utils/url')
;
var debug = function() {};
if (process.env.NODE_ENV !== 'production') {
debug = require('debug')('sockjs-client:sender:jsonp');
}
var form, area;
function createIframe(id) {
debug('createIframe', id);
try {
// ie6 dynamic iframes with target="" support (thanks Chris Lambacher)
return global.document.createElement('<iframe name="' + id + '">');
} catch (x) {
var iframe = global.document.createElement('iframe');
iframe.name = id;
return iframe;
}
}
function createForm() {
debug('createForm');
form = global.document.createElement('form');
form.style.display = 'none';
form.style.position = 'absolute';
form.method = 'POST';
form.enctype = 'application/x-www-form-urlencoded';
form.acceptCharset = 'UTF-8';
area = global.document.createElement('textarea');
area.name = 'd';
form.appendChild(area);
global.document.body.appendChild(form);
}
module.exports = function(url, payload, callback) {
debug(url, payload);
if (!form) {
createForm();
}
var id = 'a' + random.string(8);
form.target = id;
form.action = urlUtils.addQuery(urlUtils.addPath(url, '/jsonp_send'), 'i=' + id);
var iframe = createIframe(id);
iframe.id = id;
iframe.style.display = 'none';
form.appendChild(iframe);
try {
area.value = payload;
} catch (e) {
// seriously broken browsers get here
}
form.submit();
var completed = function(err) {
debug('completed', id, err);
if (!iframe.onerror) {
return;
}
iframe.onreadystatechange = iframe.onerror = iframe.onload = null;
// Opera mini doesn't like if we GC iframe
// immediately, thus this timeout.
setTimeout(function() {
debug('cleaning up', id);
iframe.parentNode.removeChild(iframe);
iframe = null;
}, 500);
area.value = '';
// It is not possible to detect if the iframe succeeded or
// failed to submit our form.
callback(err);
};
iframe.onerror = function() {
debug('onerror', id);
completed();
};
iframe.onload = function() {
debug('onload', id);
completed();
};
iframe.onreadystatechange = function(e) {
debug('onreadystatechange', id, iframe.readyState, e);
if (iframe.readyState === 'complete') {
completed();
}
};
return function() {
debug('aborted', id);
completed(new Error('Aborted'));
};
};