HTTPClient class

httpclient.js

// http://svn.janoszen.com/repos/jsfw/trunk/httpclient.js

function HTTPClient() {
  this._xhr = this._getXHR();
}

HTTPClient.prototype = {
  _xhr : undefined,
  _method : "GET",
  _url : "",
  _data : "",
  _callbacks : {
    open: [],
    headers: [],
    loading: [],
    done: [],
    successful: [],
    error: []
  },
  _methods: {
    GET : "GET",
    HEAD : "HEAD",
    POST : "POST",
    PUT : "PUT",
    DELETE : "DELETE",
    OPTIONS : "OPTIONS"
  },
  
  setMethod : function (method) {
    if (method in this._methods) {
      this._method = method;
    }
    else {
      throw "Invalid HTTP method: " + method;      
    }
  },
  
  setURL : function (url) {
    this._url = url;
  },
  
  setData : function (data) {
    this._data = data;
  },
  
  send : function () {
    this._xhr.open(this._method, this._url, true);
    this._xhr.onreadystatechange = this._callbackHandler;
    this._xhr.send(this._data);
  },
  
  isError : function () {
    var re = /^4|5/;
    if (re.test(this._xhr.status)) {
      return true;
    } else {
      return false;
    }
  },
  
  onOpened : function (callback) {
    this._callbacks.open.push(callback);
  },
  
  onHeadersReceived : function (callback) {
    this._callbacks.headers.push(callback);
  },
  
  onLoading : function (callback) {
    this._callbacks.loading.push(callback);
  },
  
  onDone : function (callback) {
    this._callbacks.done.push(callback);
  },
  
  onDoneSuccessful : function (callback) {
    this._callbacks.successful.push(callback);
  },
  
  _getXHR : window.XMLHttpRequest && (window.location.protocol !== "file:" || !window.ActiveXObject) ?
    function () {
      return new window.XMLHttpRequest();
    } :
    function () {
      try {
        return new window.ActiveXObject("Microsoft.XMLHTTP");
      } catch (e) {
      }
      throw "No HTTP client library available!";
    },
  
  _callback : function (func, xhr) {
    var callbacks = this._callbacks[func], i;
    if (callbacks) {
      for (i in callbacks) {
        if (Object.prototype.hasOwnProperty.call(callbacks, i)) {
          try {
            callbacks[i](xhr);
          } catch (e) {
            Error.handle(e);
          }
        }
      }
    }
  },
  
  _callbackHandler : function () {
    switch (this.readyState) {
      case 1:
        this._callback('open', this);
        break;
      case 2:
        this._callback('headers', this);
        break;
      case 3:
        this._callback('loading', this);
        break;
      case 4:
        this._callback('done', this);
        if (this.isError()) {
          this._callback('error', this);
        } else {
          this._callback('successful', this);
        }
        break;
    }
  }
};

/**
 * @todo Define relation between HTTPClient and HTTP.
 */
var HTTP = {
  init: function () {

  }
};

Bootstrap.registerModule("HTTP");