ajax.js

//     Zepto.js
//     (c) 2010-2013 Thomas Fuchs
//     Zepto.js may be freely distributed under the MIT license.

;(function($){
  var jsonpID = 0,
      document = window.document,
      key,
      name,
      rscript = /<script\b[^<]*(?:(?!<\/script>)<[^<]*)*<\/script>/gi,
      scriptTypeRE = /^(?:text|application)\/javascript/i,
      xmlTypeRE = /^(?:text|application)\/xml/i,
      jsonType = 'application/json',
      htmlType = 'text/html',
      blankRE = /^\s*$/

  // trigger a custom event and return false if it was cancelled
  function triggerAndReturn(context, eventName, data) {
    var event = $.Event(eventName)
    $(context).trigger(event, data)
    return !event.isDefaultPrevented()
  }

  // trigger an Ajax "global" event
  function triggerGlobal(settings, context, eventName, data) {
    if (settings.global) return triggerAndReturn(context || document, eventName, data)
  }

  // Number of active Ajax requests
  $.active = 0

  function ajaxStart(settings) {
    if (settings.global && $.active++ === 0) triggerGlobal(settings, null, 'ajaxStart')
  }
  function ajaxStop(settings) {
    if (settings.global && !(--$.active)) triggerGlobal(settings, null, 'ajaxStop')
  }

  // triggers an extra global event "ajaxBeforeSend" that's like "ajaxSend" but cancelable
  function ajaxBeforeSend(xhr, settings) {
    var context = settings.context
    if (settings.beforeSend.call(context, xhr, settings) === false ||
        triggerGlobal(settings, context, 'ajaxBeforeSend', [xhr, settings]) === false)
      return false

    triggerGlobal(settings, context, 'ajaxSend', [xhr, settings])
  }
  function ajaxSuccess(data, xhr, settings) {
    var context = settings.context, status = 'success'
    settings.success.call(context, data, status, xhr)
    triggerGlobal(settings, context, 'ajaxSuccess', [xhr, settings, data])
    ajaxComplete(status, xhr, settings)
  }
  // type: "timeout", "error", "abort", "parsererror"
  function ajaxError(error, type, xhr, settings) {
    var context = settings.context
    settings.error.call(context, xhr, type, error)
    triggerGlobal(settings, context, 'ajaxError', [xhr, settings, error || type])
    ajaxComplete(type, xhr, settings)
  }
  // status: "success", "notmodified", "error", "timeout", "abort", "parsererror"
  function ajaxComplete(status, xhr, settings) {
    var context = settings.context
    settings.complete.call(context, xhr, status)
    triggerGlobal(settings, context, 'ajaxComplete', [xhr, settings])
    ajaxStop(settings)
  }

  // Empty function, used as default callback
  function empty() {}

  $.ajaxJSONP = function(options){
    if (!('type' in options)) return $.ajax(options)

    var _callbackName = options.jsonpCallback,
      callbackName = ($.isFunction(_callbackName) ?
        _callbackName() : _callbackName) || ('jsonp' + (++jsonpID)),
      script = document.createElement('script'),
      cleanup = function() {
        clearTimeout(abortTimeout)
        $(script).remove()
        delete window[callbackName]
      },
      abort = function(type){
        cleanup()
        // In case of manual abort or timeout, keep an empty function as callback
        // so that the SCRIPT tag that eventually loads won't result in an error.
        if (!type || type == 'timeout') window[callbackName] = empty
        ajaxError(null, type || 'abort', xhr, options)
      },
      xhr = { abort: abort }, abortTimeout

    if (ajaxBeforeSend(xhr, options) === false) {
      abort('abort')
      return false
    }

    window[callbackName] = function(data){
      cleanup()
      ajaxSuccess(data, xhr, options)
    }

    script.onerror = function() { abort('error') }

    script.src = options.url.replace(/=\?/, '=' + callbackName)
    $('head').append(script)

    if (options.timeout > 0) abortTimeout = setTimeout(function(){
      abort('timeout')
    }, options.timeout)

    return xhr
  }

  $.ajaxSettings = {
    // Default type of request
    type: 'GET',
    // Callback that is executed before request
    beforeSend: empty,
    // Callback that is executed if the request succeeds
    success: empty,
    // Callback that is executed the the server drops error
    error: empty,
    // Callback that is executed on request complete (both: error and success)
    complete: empty,
    // The context for the callbacks
    context: null,
    // Whether to trigger "global" Ajax events
    global: true,
    // Transport
    xhr: function () {
      return new window.XMLHttpRequest()
    },
    // MIME types mapping
    // IIS returns Javascript as "application/x-javascript"
    accepts: {
      script: 'text/javascript, application/javascript, application/x-javascript',
      json:   jsonType,
      xml:    'application/xml, text/xml',
      html:   htmlType,
      text:   'text/plain'
    },
    // Whether the request is to another domain
    crossDomain: false,
    // Default timeout
    timeout: 0,
    // Whether data should be serialized to string
    processData: true,
    // Whether the browser should be allowed to cache GET responses
    cache: true
  }

  function mimeToDataType(mime) {
    if (mime) mime = mime.split(';', 2)[0]
    return mime && ( mime == htmlType ? 'html' :
      mime == jsonType ? 'json' :
      scriptTypeRE.test(mime) ? 'script' :
      xmlTypeRE.test(mime) && 'xml' ) || 'text'
  }

  function appendQuery(url, query) {
    if (query == '') return url
    return (url + '&' + query).replace(/[&?]{1,2}/, '?')
  }

  // serialize payload and append it to the URL for GET requests
  function serializeData(options) {
    if (options.processData && options.data && $.type(options.data) != "string")
      options.data = $.param(options.data, options.traditional)
    if (options.data && (!options.type || options.type.toUpperCase() == 'GET'))
      options.url = appendQuery(options.url, options.data), options.data = null
  }

  $.ajax = function(options){
    var settings = $.extend({}, options || {})
    for (key in $.ajaxSettings) if (settings[key] === undefined) settings[key] = $.ajaxSettings[key]

    ajaxStart(settings)

    if (!settings.crossDomain) settings.crossDomain = /^([\w-]+:)?\/\/([^\/]+)/.test(settings.url) &&
      RegExp.$2 != window.location.host

    if (!settings.url) settings.url = window.location.toString()
    serializeData(settings)
    if (settings.cache === false) settings.url = appendQuery(settings.url, '_=' + Date.now())

    var dataType = settings.dataType, hasPlaceholder = /=\?/.test(settings.url)
    if (dataType == 'jsonp' || hasPlaceholder) {
      if (!hasPlaceholder)
        settings.url = appendQuery(settings.url,
          settings.jsonp ? (settings.jsonp + '=?') : settings.jsonp === false ? '' : 'callback=?')
      return $.ajaxJSONP(settings)
    }

    var mime = settings.accepts[dataType],
        baseHeaders = { },
        protocol = /^([\w-]+:)\/\//.test(settings.url) ? RegExp.$1 : window.location.protocol,
        xhr = settings.xhr(), abortTimeout

    if (!settings.crossDomain) baseHeaders['X-Requested-With'] = 'XMLHttpRequest'
    baseHeaders['Accept'] = mime || '*/*'
    if (mime = settings.mimeType || mime) {
      if (mime.indexOf(',') > -1) mime = mime.split(',', 2)[0]
      xhr.overrideMimeType && xhr.overrideMimeType(mime)
    }
    if (settings.contentType || (settings.contentType !== false && settings.data && settings.type.toUpperCase() != 'GET'))
      baseHeaders['Content-Type'] = (settings.contentType || 'application/x-www-form-urlencoded')
    settings.headers = $.extend(baseHeaders, settings.headers || {})

    xhr.onreadystatechange = function(){
      if (xhr.readyState == 4) {
        xhr.onreadystatechange = empty
        clearTimeout(abortTimeout)
        var result, error = false
        if ((xhr.status >= 200 && xhr.status < 300) || xhr.status == 304 || (xhr.status == 0 && protocol == 'file:')) {
          dataType = dataType || mimeToDataType(settings.mimeType || xhr.getResponseHeader('content-type'))
          result = xhr.responseText

          try {
            // http://perfectionkills.com/global-eval-what-are-the-options/
            if (dataType == 'script')    (1,eval)(result)
            else if (dataType == 'xml')  result = xhr.responseXML
            else if (dataType == 'json') result = blankRE.test(result) ? null : $.parseJSON(result)
          } catch (e) { error = e }

          if (error) ajaxError(error, 'parsererror', xhr, settings)
          else ajaxSuccess(result, xhr, settings)
        } else {
          ajaxError(xhr.statusText || null, xhr.status ? 'error' : 'abort', xhr, settings)
        }
      }
    }

    if (ajaxBeforeSend(xhr, settings) === false) {
      xhr.abort()
      return false
    }

    if (settings.xhrFields) for (name in settings.xhrFields) xhr[name] = settings.xhrFields[name]

    var async = 'async' in settings ? settings.async : true
    xhr.open(settings.type, settings.url, async)

    for (name in settings.headers) xhr.setRequestHeader(name, settings.headers[name])

    if (settings.timeout > 0) abortTimeout = setTimeout(function(){
        xhr.onreadystatechange = empty
        xhr.abort()
        ajaxError(null, 'timeout', xhr, settings)
      }, settings.timeout)

    // avoid sending empty string (#319)
    xhr.send(settings.data ? settings.data : null)
    return xhr
  }

  // handle optional data/success arguments
  function parseArguments(url, data, success, dataType) {
    var hasData = !$.isFunction(data)
    return {
      url:      url,
      data:     hasData  ? data : undefined,
      success:  !hasData ? data : $.isFunction(success) ? success : undefined,
      dataType: hasData  ? dataType || success : success
    }
  }

  $.get = function(url, data, success, dataType){
    return $.ajax(parseArguments.apply(null, arguments))
  }

  $.post = function(url, data, success, dataType){
    var options = parseArguments.apply(null, arguments)
    options.type = 'POST'
    return $.ajax(options)
  }

  $.getJSON = function(url, data, success){
    var options = parseArguments.apply(null, arguments)
    options.dataType = 'json'
    return $.ajax(options)
  }

  $.fn.load = function(url, data, success){
    if (!this.length) return this
    var self = this, parts = url.split(/\s/), selector,
        options = parseArguments(url, data, success),
        callback = options.success
    if (parts.length > 1) options.url = parts[0], selector = parts[1]
    options.success = function(response){
      self.html(selector ?
        $('<div>').html(response.replace(rscript, "")).find(selector)
        : response)
      callback && callback.apply(self, arguments)
    }
    $.ajax(options)
    return this
  }

  var escape = encodeURIComponent

  function serialize(params, obj, traditional, scope){
    var type, array = $.isArray(obj), hash = $.isPlainObject(obj)
    $.each(obj, function(key, value) {
      type = $.type(value)
      if (scope) key = traditional ? scope :
        scope + '[' + (hash || type == 'object' || type == 'array' ? key : '') + ']'
      // handle data in serializeArray() format
      if (!scope && array) params.add(value.name, value.value)
      // recurse into nested objects
      else if (type == "array" || (!traditional && type == "object"))
        serialize(params, value, traditional, key)
      else params.add(key, value)
    })
  }

  $.param = function(obj, traditional){
    var params = []
    params.add = function(k, v){ this.push(escape(k) + '=' + escape(v)) }
    serialize(params, obj, traditional)
    return params.join('&').replace(/%20/g, '+')
  }
})(Zepto)