An AJAX plugin for JSL
此脚本不应直接安装，它是一个供其他脚本使用的外部库。如果您需要使用该库，请在脚本元属性加入：// @require https://update.greasyfork.org/scripts/2817/7911/JSL%20-%20AJAX%20plugin.js
// ==UserScript==
// @name JSL - AJAX plugin
// @namespace http://userscripts.org/users/23652
// @description An AJAX plugin for JSL
// @include *
// @version 1.1.0
// @grant GM_xmlhttpRequest
// ==/UserScript==
/* CHANGELOG
1.1.0 (3/28/2014)
- added JSL.ajaxClear() to clear all current and pending requests
1.0.21 (10/6/2013)
- fixed bug with .clear()
1.0.2 (10/6/2013)
- added a new option: async
false (default) ==> synchronous, but non-freezing requests (sequential)
waits for previous request to finish before starting a new one
true ==> sends all requests immediately when they are added to the queue
- fixed delay issue.
the next request would get run on the 'onprogress' & 'onreadystatechange' events
instead of when they actually load fully
- added a .clear() method
it may be called on any ajax instance like JSL.ajax(...).clear()
it can even simply be called as JSL.ajax().clear()
it will clear ALL requests at the moment
1.0.1 (10/3/2013)
- fixed small bug with passing a url array
- fixed bug not allowing HEAD requests to be recognized
1.0.0 (10/1/2013)
- created
*/
(function (undefined) {
'use strict'; // use strict mode in ECMAScript-5
var queue = [], // the request queue
blank = function () {}, // blank function to use as default callback
xhrInProgress = false, // boolean to know if we should load the next request
xhrCleared = false; // boolean to know if the xhr has been cleared and if
// we should execute any of the callbacks
var core = {
// object
'hasOwnProperty' : Object.prototype.hasOwnProperty
};
function copyObject(o) {
var key, value, newO = {};
for (key in o) {
value = o[key];
if (core.hasOwnProperty.call(o, key) && value != null) {
newO[key] = value;
}
}
return newO;
}
function toDataString(o) {
var key, value, dataString = '';
for (key in o) {
value = o[key];
if (core.hasOwnProperty.call(o, key) && value != null) {
dataString += key + '=' + encodeURIComponent(value) + '&';
}
}
return dataString.slice(0, -1);
}
function xhr() {
var req = queue[0], // get the object which is first in the queue
xhrObj = {}, key;
function handleEvents(type, resp, event) {
var event = event || {}, newResp, context;
req.delay = req.delay > 15 ? req.delay : 15; // don't want to mess up callbacks
if (xhrCleared === true) {
return;
}
if (req[type] !== blank) {
// define a new response object to give to the user
newResp = {
lengthComputable : resp.lengthComputable || event.lengthComputable || null,
loaded : resp.loaded || event.loaded || null,
readyState : resp.readyState,
responseHeaders : resp.responseHeaders ||
( typeof resp.getAllResponseHeaders === 'function' ? resp.getAllResponseHeaders() : null) || '',
responseText : resp.responseText,
status : resp.status,
statusText : resp.statusText,
total : resp.total || event.total || null,
url : resp.finalUrl || req.url,
};
// allow new requests to be run if our request is done
if (type === 'onerror' || type === 'onload') {
xhrInProgress = false;
// run the next in queue, if any
window.setTimeout(xhr, req.delay);
}
// run the callback
context = req.context || newResp;
req[type].call(context, newResp);
}
}
if ( req && (xhrInProgress === false || req.async === true) && queue.length > 0) {
// make it so no other requests get run while we
// run this one, if async isn't enabled
xhrInProgress = true;
// remove the first item in the queue if it is going to be run
queue.shift();
if (typeof GM_xmlhttpRequest === 'function') {
if (req.method.toUpperCase() === 'GET' && req.data !== '') {
req.url += '?' + req.data;
req.data = '';
}
GM_xmlhttpRequest({
'data' : req.data,
'headers' : req.headers,
'method' : req.method,
'onerror' : function (resp) {
handleEvents('onerror', resp);
},
'onload' : function (resp) {
handleEvents('onload', resp);
},
'onreadystatechange' : function (resp) {
handleEvents('onreadystatechange', resp);
},
'onprogress' : function (resp) {
handleEvents('onprogress', resp);
},
'url' : req.url,
});
} else if (typeof XMLHttpRequest === 'function' || typeof ActiveXObject === 'function') {
xhrObj = XMLHttpRequest ? new XMLHttpRequest() : new ActiveXObject('Microsoft.XMLHTTP');
// set events
xhrObj.onload = function (resp) {
handleEvents('onload', xhrObj);
};
xhrObj.onerror = function (resp) {
handleEvents('onerror', xhrObj);
};
xhrObj.onprogress = function (resp) {
handleEvents('onprogress', xhrObj, resp);
};
if (req.mimeType !== '') {
xhrObj.overrideMimeType(req.mimeType);
}
// add headers
for (key in req.headers) {
xhrObj.setRequestHeader( key, req.headers[key] );
}
xhrObj.open(req.method, req.url, true);
xhrObj.send( (req.data || null) );
}
}
}
function init(url, settings) {
var urls = [],
realSettings = { // defaults
async : false,
data : '',
headers : {},
method : 'GET',
mimeType : '',
onload : blank,
onerror : blank,
onprogress : blank,
onreadystatechange : blank,
delay : 0
},
key, value;
if (typeof url === 'string') {
urls.push(url);
} else if (JSL.typeOf(url) === 'array') {
urls = urls.concat(url);
}
if (JSL.typeOf(settings) === 'object') {
for (key in settings) {
value = settings[key];
switch (key) {
case 'async': {
if (typeof value === 'boolean') {
realSettings[key] = value;
}
break;
}
case 'context': {
if (value != null) {
realSettings[key] = value;
}
break;
}
case 'data': {
if (typeof value === 'string') {
realSettings[key] = value;
} else if (JSL.typeOf(value) === 'object') {
realSettings[key] = toDataString(value);
}
break;
}
case 'delay': {
if (typeof value === 'number' && value > 0) {
realSettings[key] = value;
}
break;
}
case 'headers': {
if (JSL.typeOf(value) === 'object') {
realSettings[key] = toDataString(value);
}
break;
}
case 'method': {
if ( typeof value === 'string' && /get|post|head/i.test(value) ) {
realSettings[key] = value.toUpperCase();
}
break;
}
case 'mimeType': {
if (typeof value === 'string') {
realSettings[key] = value;
}
break;
}
case 'onload': case 'onerror': case 'onreadystatechange': case 'onprogress': {
if (typeof value === 'function') {
realSettings[key] = value;
}
break;
}
}
}
}
// add an object to the queue for each url
if (urls.length > 0) {
JSL.each(urls, function (url) {
var newO = copyObject(realSettings);
newO.url = url;
queue.push(newO);
});
// enable ajax if it was cleared earlier
xhrCleared = false;
// run the xhr function
// it will determine whether or not a request needs to be sent
xhr();
}
}
init.prototype = {
constructor: init,
clear : function() {
queue.length = 0;
xhrInProgress = false;
xhrCleared = true;
},
get length() {
return queue.length;
}
};
JSL.extend({
ajax : function (url, settings) {
return new init(url, settings);
},
ajaxClear : init.prototype.clear
});
}());