Open-ILS/src/javascript/lib/js/opac/RemoteRequest.js

   1 var XML_HTTP_GATEWAY = "gateway";
   2 var XML_HTTP_SERVER = "gapines.org";
   3 var XML_HTTP_MAX_TRIES = 3;
   4
   5 var _allrequests = new Array();
   6
   7 function cleanRemoteRequests() {
   8         for( var i = 0; i!= _allrequests.length; i++ ) {
   9                 var r = _allrequests[i];
  10                 r.xmlhttp.onreadystatechange = function(){};
  11                 r.xmlhttp                       = null;
  12                 r.callback                      = null;
  13                 r.userdata                      = null;
  14                 _allrequests[i]         = null;
  15         }
  16 }
  17
  18 /* ----------------------------------------------------------------------- */
  19 /* Request object */
  20 function RemoteRequest( service, method ) {
  21
  22         _allrequests.push(this);
  23
  24         this.service    = service;
  25         this.method             = method;
  26         this.xmlhttp    = false;
  27         this.name               = null;
  28         this.sendCount = 0;
  29
  30         this.type               = "POST"; /* default */
  31         this.id                 = service + method + Math.random();
  32         this.cancelled = false;
  33
  34         var i = 2;
  35         this.params = "";
  36
  37         while(i < arguments.length) {
  38                 var object = js2JSON(arguments[i++]);
  39                 this.params += "&param=" + encodeURIComponent(object);
  40         }
  41
  42         if(!this.params) { this.params = ""; }
  43         this.param_string = "service=" + service + "&method=" + method + this.params;
  44
  45         if( ! this.type || ! this.service || ! this.method ) {
  46                 alert( "ERROR IN REQUEST PARAMS");
  47                 return null;
  48         }
  49
  50         if( this.buildXMLRequest() == null )
  51                 alert("NEWER BROWSER");
  52 }
  53
  54 /* constructs our XMLHTTPRequest object */
  55 RemoteRequest.prototype.buildXMLRequest = function() {
  56
  57         try {
  58                 this.xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
  59         } catch (e) {
  60                 try {
  61                         this.xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
  62                 } catch (E) {
  63                         this.xmlhttp = false;
  64                 }
  65         }
  66
  67         if (!this.xmlhttp && typeof XMLHttpRequest!='undefined') {
  68                 this.xmlhttp = new XMLHttpRequest();
  69         }
  70
  71         if(!this.xmlhttp) {
  72                 alert("NEEDS NEWER JAVASCRIPT for XMLHTTPRequest()");
  73                 return null;
  74         }
  75
  76         return true;
  77 }
  78
  79
  80 /* define the callback we use when this request has received
  81         all of its data */
  82 RemoteRequest.prototype.setCompleteCallback = function(callback) {
  83
  84         if(this.cancelled) return;
  85         var object = this;
  86         var xml = this.xmlhttp;
  87
  88         xml.onreadystatechange = function() {
  89                 if( xml.readyState == 4 ) {
  90
  91                         try {
  92                                 if(object.cancelled) return;
  93                                 callback(object);
  94
  95                         } catch(E) {
  96
  97                                 /* if we receive a communication error, retry the request up
  98                                         to XML_HTTP_MAX_TRIES attempts */
  99                                 if( instanceOf(E, EXCommunication) ) {
 100
 101                                         if(object.sendCount >= XML_HTTP_MAX_TRIES ) {
 102                                                 if(isXUL()) {
 103                                                         throw object;
 104                                                 } else {
 105                                                         alert("Arrrgghh, Matey! Error communicating:\n" +
 106                                                                  E  + "\n" + object.param_string);
 107                                                 }
 108                                         } else {
 109                                                 object.buildXMLRequest();
 110                                                 object.send();
 111                                                 return;
 112                                         }
 113                                 } else { throw E; }
 114                         } finally { object = null; }
 115                 }
 116         }
 117 }
 118
 119
 120 /* http by default.  This makes it https. *ONLY works when
 121         embedded in a XUL app. */
 122 RemoteRequest.prototype.setSecure = function(bool) {
 123         this.secure = bool;
 124 }
 125
 126 /** Send the request
 127   * By default, all calls are asynchronous.  if 'blocking' is
 128   * set to true, then the call will block until a response
 129   * is received.  If blocking, callbacks will not be called.
 130   * In other words, you can assume the data is avaiable
 131   * (getResponseObject()) as soon as the send call returns.
 132   */
 133 RemoteRequest.prototype.send = function(blocking) {
 134
 135         if(this.cancelled) return;
 136
 137         /* determine the xmlhttp server dynamically */
 138         var url = location.protocol + "//" + location.host + "/" + XML_HTTP_GATEWAY;
 139
 140         if(isXUL()) {
 141                 if(this.secure)
 142                         url =   "https://" + XML_HTTP_SERVER + "/" + XML_HTTP_GATEWAY;
 143                 else
 144                         url =   "http://" + XML_HTTP_SERVER + "/" + XML_HTTP_GATEWAY;
 145         }
 146
 147         var data = null;
 148
 149         if( this.type == 'GET' ) {
 150                 url +=  "?" + this.param_string;
 151         }
 152
 153         if(blocking) {
 154                 this.xmlhttp.open(this.type, url, false);
 155         } else {
 156                 this.xmlhttp.open(this.type, url, true);
 157         }
 158
 159
 160         if( this.type == 'POST' ) {
 161                 data = this.param_string;
 162                 this.xmlhttp.setRequestHeader('Content-Type',
 163                                 'application/x-www-form-urlencoded');
 164         }
 165
 166         this.xmlhttp.send( data );
 167         this.sendCount += 1;
 168         return this;
 169 }
 170
 171 /* returns the actual response text from the request */
 172 RemoteRequest.prototype.getText = function() {
 173         return this.xmlhttp.responseText;
 174 }
 175
 176 RemoteRequest.prototype.isReady = function() {
 177         return this.xmlhttp.readyState == 4;
 178 }
 179
 180
 181 /* returns the JSON->js result object  */
 182 RemoteRequest.prototype.getResultObject = function() {
 183         //this.callback = null;
 184         if(this.cancelled) return null;
 185
 186         var text = this.xmlhttp.responseText;
 187         var obj = JSON2js(text);
 188
 189         if(obj == null) {
 190                 return null;
 191         }
 192
 193         if(obj.is_err) {
 194                 throw new EXCommunication(obj.err_msg);
 195         }
 196
 197         if( obj[0] != null && obj[1] == null )
 198                 obj = obj[0];
 199
 200         /* these are user level exceptions from the server code */
 201         if(instanceOf(obj, ex)) {
 202                 /* the opac will go ahead and spit out the error msg */
 203                 if(!isXUL()) alert(obj.err_msg());
 204                 throw obj;
 205         }
 206
 207         if(instanceOf(obj, perm_ex)) {
 208                 /* the opac will go ahead and spit out the error msg */
 209                 if(!isXUL()) alert(obj.err_msg());
 210                 throw obj;
 211         }
 212
 213         return obj;
 214 }
 215
 216 /* adds a new parameter to the request */
 217 RemoteRequest.prototype.addParam = function(param) {
 218         var string = encodeURIComponent(js2JSON(param));
 219         this.param_string += "&param=" + string;
 220 }
 221