Open-ILS/web/opac/common/js/RemoteRequest.js

   1 var XML_HTTP_GATEWAY = "gateway";
   2 var XML_HTTP_SERVER = "dev.gapines.org";
   3 var XML_HTTP_MAX_TRIES = 3;
   4
   5 //var IAMXUL = false;
   6 function isXUL() { try { if(IAMXUL) return true;}catch(e){return false;}; }
   7
   8 /* some communication exceptions */
   9 function EX(message) { this.init(message); }
  10 EX.prototype.init = function(message) { this.message = message; }
  11 EX.prototype.toString = function() { return "\n *** Exception Occured \n" + this.message; }
  12 EXCommunication.prototype              = new EX();
  13 EXCommunication.prototype.constructor  = EXCommunication;
  14 EXCommunication.baseClass              = EX.prototype.constructor;
  15 function EXCommunication(message) { this.classname="EXCommunication"; this.init("EXCommunication: " + message); }
  16 /* ------------------------------------------------ */
  17
  18
  19 var _allrequests = {};
  20
  21 function cleanRemoteRequests() {
  22         for( var i in _allrequests )
  23                 destroyRequest(_allrequests[i]);
  24 }
  25
  26 function destroyRequest(r) {
  27         if(r == null) return;
  28
  29         if( r.xmlhttp ) {
  30                 /* this has to come before abort() or IE will puke on you */
  31                 r.xmlhttp.onreadystatechange = function(){};
  32                 r.abort();
  33                 r.xmlhttp                               = null;
  34         }
  35
  36         r.callback                              = null;
  37         r.userdata                              = null;
  38         _allrequests[r.id]      = null;
  39 }
  40
  41 /* ----------------------------------------------------------------------- */
  42 /* Request object */
  43 function RemoteRequest( service, method ) {
  44
  45
  46         this.service    = service;
  47         this.method             = method;
  48         this.xmlhttp    = false;
  49         this.name               = null;
  50         this.sendCount = 0;
  51
  52         this.type               = "POST"; /* default */
  53         this.id                 = service + method + Math.random();
  54         this.cancelled = false;
  55
  56         _allrequests[this.id] = this;
  57
  58         var i = 2;
  59         this.params = "";
  60
  61         while(i < arguments.length) {
  62                 var object = js2JSON(arguments[i++]);
  63                 this.params += "&param=" + encodeURIComponent(object);
  64         }
  65
  66         if(!this.params) { this.params = ""; }
  67         this.param_string = "service=" + service + "&method=" + method + this.params;
  68         if( this.buildXMLRequest() == null ) alert("Browser is not supported!");
  69 }
  70
  71 RemoteRequest.prototype.abort = function() {
  72         if( this.xmlhttp ) this.xmlhttp.abort();
  73 }
  74
  75 /* constructs our XMLHTTPRequest object */
  76 RemoteRequest.prototype.buildXMLRequest = function() {
  77
  78         var x;
  79         try {
  80                 x = new ActiveXObject("Msxml2.XMLHTTP");
  81         } catch (e) {
  82                 try {
  83                         x = new ActiveXObject("Microsoft.XMLHTTP");
  84                 } catch (E) {
  85                         x = false;
  86                 }
  87         }
  88
  89         if (!x && typeof XMLHttpRequest!='undefined') x = new XMLHttpRequest();
  90
  91         if(!x) {
  92                 alert("NEEDS NEWER JAVASCRIPT for XMLHTTPRequest()");
  93                 return null;
  94         }
  95
  96         this.xmlhttp = x;
  97         return true;
  98 }
  99
 100
 101 function _remoteRequestCallback(id) {
 102
 103         var object = _allrequests[id];
 104         if(object.cancelled) return;
 105
 106         if( object.xmlhttp.readyState == 4 ) {
 107                 try {
 108                         object.callback(object);
 109                 } catch(E) {
 110
 111                         /* if we receive a communication error, retry the request up
 112                                 to XML_HTTP_MAX_TRIES attempts */
 113                         if( E && E.classname == "EXCommunication" ) {
 114
 115                                 //try { dump('Communication Error: ' + E ); } catch(e){}
 116                                 alert('Debug:  Communication Error: ' + E );
 117
 118                                 if(object.sendCount >= XML_HTTP_MAX_TRIES ) {
 119                                         if(isXUL()) throw object;
 120                                          else alert("Arrrgghh, Matey! Error communicating:\n" + E  + "\n" + object.param_string);
 121                                 } else {
 122                                         object.buildXMLRequest();
 123                                         object.send();
 124                                         return;
 125                                 }
 126                         } else { throw E; }
 127
 128                 } finally {
 129                         destroyRequest(object);
 130                         object = null;
 131                 }
 132         }
 133 }
 134
 135
 136 /* define the callback we use when this request has received
 137         all of its data */
 138 RemoteRequest.prototype.setCompleteCallback = function(callback) {
 139         if(this.cancelled) return;
 140         this.callback = callback;
 141         var id = this.id;
 142         this.xmlhttp.onreadystatechange = function() { _remoteRequestCallback(id); }
 143 }
 144
 145
 146 /* http by default.  This makes it https. *ONLY works when
 147         embedded in a XUL app. */
 148 RemoteRequest.prototype.setSecure = function(bool) {
 149         this.secure = bool;
 150 }
 151
 152 RemoteRequest.prototype.send = function(blocking) {
 153
 154         if(this.cancelled) return;
 155
 156         /* determine the xmlhttp server dynamically */
 157         var url = location.protocol + "//" + location.host + "/" + XML_HTTP_GATEWAY;
 158
 159         if(isXUL()) {
 160                 if(this.secure || url.match(/^https:/) )
 161                         url =   "https://" + XML_HTTP_SERVER + "/" + XML_HTTP_GATEWAY;
 162                 else
 163                         url =   "http://" + XML_HTTP_SERVER + "/" + XML_HTTP_GATEWAY;
 164         }
 165
 166         var data = null;
 167         if( this.type == 'GET' ) url +=  "?" + this.param_string;
 168
 169         try {
 170
 171                 if(blocking) this.xmlhttp.open(this.type, url, false);
 172                 else this.xmlhttp.open(this.type, url, true);
 173
 174         } catch(E) {
 175                 alert("Fatal error opening XMLHTTPRequest for URL:\n" + url + '\n');
 176                 return;
 177         }
 178
 179
 180         if( this.type == 'POST' ) {
 181                 data = this.param_string;
 182                 this.xmlhttp.setRequestHeader('Content-Type',
 183                                 'application/x-www-form-urlencoded');
 184         }
 185
 186         try{ this.xmlhttp.send( data ); } catch(e){}
 187
 188         this.sendCount += 1;
 189         return this;
 190 }
 191
 192 /* returns the actual response text from the request */
 193 RemoteRequest.prototype.getText = function() {
 194         return this.xmlhttp.responseText;
 195 }
 196
 197 RemoteRequest.prototype.isReady = function() {
 198         return this.xmlhttp.readyState == 4;
 199 }
 200
 201
 202 /* returns the JSON->js result object  */
 203 RemoteRequest.prototype.getResultObject = function() {
 204
 205         if(this.cancelled) return null;
 206         if(!this.xmlhttp) return null;
 207
 208         var text = this.xmlhttp.responseText;
 209         if(text == "" || text == " " || text == null) null;
 210
 211         var obj = JSON2js(text);
 212         if(!obj) return null;
 213
 214         if( obj.status != 200 ) {
 215                 if(!isXUL()) {
 216                         alert("A Server Error Occured.  Debug information follows:\n" +
 217                                 "Status: " + obj.status + '\n' + obj.debug + '\n'
 218                                 + 'Payload: ' + js2JSON(obj.payload) + '\n');
 219                 } else {
 220                         dump('Remote Request Error:' +
 221                                         '\ncode = '             + obj.status +
 222                                         '\ndebug: '             + obj.debug +
 223                                         '\npayload: '   + js2JSON(obj.payload));
 224                         throw obj;
 225                 }
 226         }
 227
 228         var payload = obj.payload;
 229         if(!payload || payload.length == 0) return null;
 230         payload = (payload.length == 1) ? payload[0] : payload;
 231
 232         if(payload.__isfieldmapper && payload.classname == "perm_ex") {
 233                 if(!isXUL()) alert(payload.err_msg());
 234                 throw payload;
 235         }
 236
 237         return payload;
 238 }
 239
 240 /* adds a new parameter to the request */
 241 RemoteRequest.prototype.addParam = function(param) {
 242         var string = encodeURIComponent(js2JSON(param));
 243         this.param_string += "&param=" + string;
 244 }
 245