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

   1 var XML_HTTP_GATEWAY = "gateway";
   2 var XML_HTTP_SERVER = "";
   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 abortAllRequests() {
  27         for( var i in _allrequests ) {
  28                 var r = _allrequests[i];
  29                 if(r) {
  30                         /* this has to come before abort() or IE will puke on you */
  31                         r.xmlhttp.onreadystatechange = function(){};
  32                         r.abort();
  33                         destroyRequest(r);
  34                 }
  35         }
  36 }
  37
  38 function destroyRequest(r) {
  39         if(r == null) return;
  40
  41         if( r.xmlhttp ) {
  42                 r.xmlhttp.onreadystatechange = function(){};
  43                 r.xmlhttp = null;
  44         }
  45
  46         r.callback                              = null;
  47         r.userdata                              = null;
  48         _allrequests[r.id]      = null;
  49 }
  50
  51 /* ----------------------------------------------------------------------- */
  52 /* Request object */
  53 function RemoteRequest( service, method ) {
  54
  55
  56         this.service    = service;
  57         this.method             = method;
  58         this.xmlhttp    = false;
  59         this.name               = null;
  60         this.sendCount = 0;
  61
  62         this.type               = "POST"; /* default */
  63         this.id                 = service + method + Math.random();
  64         this.cancelled = false;
  65
  66         _allrequests[this.id] = this;
  67
  68         var i = 2;
  69         this.params = "";
  70
  71         while(i < arguments.length) {
  72                 var object = js2JSON(arguments[i++]);
  73                 this.params += "&param=" + encodeURIComponent(object);
  74         }
  75
  76         if(!this.params) { this.params = ""; }
  77         this.param_string = "service=" + service + "&method=" + method + this.params;
  78         if( this.buildXMLRequest() == null ) alert("Browser is not supported!");
  79 }
  80
  81 RemoteRequest.prototype.abort = function() {
  82         if( this.xmlhttp ) this.xmlhttp.abort();
  83 }
  84
  85 /* constructs our XMLHTTPRequest object */
  86 RemoteRequest.prototype.buildXMLRequest = function() {
  87
  88         var x;
  89         try {
  90                 x = new ActiveXObject("Msxml2.XMLHTTP");
  91         } catch (e) {
  92                 try {
  93                         x = new ActiveXObject("Microsoft.XMLHTTP");
  94                 } catch (E) {
  95                         x = false;
  96                 }
  97         }
  98
  99         if (!x && typeof XMLHttpRequest!='undefined') x = new XMLHttpRequest();
 100
 101         if(!x) {
 102                 alert("NEEDS NEWER JAVASCRIPT for XMLHTTPRequest()");
 103                 return null;
 104         }
 105
 106         this.xmlhttp = x;
 107         return true;
 108 }
 109
 110
 111 function _remoteRequestCallback(id) {
 112
 113         var object = _allrequests[id];
 114         if(object.cancelled) return;
 115
 116         if( object.xmlhttp.readyState == 4 ) {
 117                 try {
 118                         object.callback(object);
 119                 } catch(E) {
 120
 121                         /* if we receive a communication error, retry the request up
 122                                 to XML_HTTP_MAX_TRIES attempts */
 123                         if( E && E.classname == "EXCommunication" ) {
 124
 125                                 //try { dump('Communication Error: ' + E ); } catch(e){}
 126                                 alert('Debug:  Communication Error: ' + E );
 127
 128                                 if(object.sendCount >= XML_HTTP_MAX_TRIES ) {
 129                                         if(isXUL()) throw object;
 130                                          else alert("Arrrgghh, Matey! Error communicating:\n" + E  + "\n" + object.param_string);
 131                                 } else {
 132                                         object.buildXMLRequest();
 133                                         object.send();
 134                                         return;
 135                                 }
 136                         } else { throw E; }
 137
 138                 } finally {
 139                         destroyRequest(object);
 140                         object = null;
 141                 }
 142         }
 143 }
 144
 145
 146 /* define the callback we use when this request has received
 147         all of its data */
 148 RemoteRequest.prototype.setCompleteCallback = function(callback) {
 149         if(this.cancelled) return;
 150         this.callback = callback;
 151         var id = this.id;
 152         this.xmlhttp.onreadystatechange = function() { _remoteRequestCallback(id); }
 153 }
 154
 155
 156 /* http by default.  This makes it https. *ONLY works when
 157         embedded in a XUL app. */
 158 RemoteRequest.prototype.setSecure = function(bool) {
 159         this.secure = bool;
 160 }
 161
 162 RemoteRequest.prototype.send = function(blocking) {
 163
 164         if(this.cancelled) return;
 165
 166         /* determine the xmlhttp server dynamically */
 167         var url = location.protocol + "//" + location.host + "/" + XML_HTTP_GATEWAY;
 168
 169         if(isXUL() && XML_HTTP_SERVER) {
 170                 if(this.secure || url.match(/^https:/) )
 171                         url =   "https://" + XML_HTTP_SERVER + "/" + XML_HTTP_GATEWAY;
 172                 else
 173                         url =   "http://" + XML_HTTP_SERVER + "/" + XML_HTTP_GATEWAY;
 174         }
 175
 176         var data = null;
 177         if( this.type == 'GET' ) url +=  "?" + this.param_string;
 178
 179         try {
 180
 181                 if(blocking) this.xmlhttp.open(this.type, url, false);
 182                 else this.xmlhttp.open(this.type, url, true);
 183
 184         } catch(E) {
 185                 alert("Fatal error opening XMLHTTPRequest for URL:\n" + url + '\n');
 186                 return;
 187         }
 188
 189
 190         if( this.type == 'POST' ) {
 191                 data = this.param_string;
 192                 this.xmlhttp.setRequestHeader('Content-Type',
 193                                 'application/x-www-form-urlencoded');
 194         }
 195
 196         try{ this.xmlhttp.send( data ); } catch(e){}
 197
 198         this.sendCount += 1;
 199         return this;
 200 }
 201
 202 /* returns the actual response text from the request */
 203 RemoteRequest.prototype.getText = function() {
 204         return this.xmlhttp.responseText;
 205 }
 206
 207 RemoteRequest.prototype.isReady = function() {
 208         return this.xmlhttp.readyState == 4;
 209 }
 210
 211
 212 /* returns the JSON->js result object  */
 213 RemoteRequest.prototype.getResultObject = function() {
 214
 215         if(this.cancelled) return null;
 216         if(!this.xmlhttp) return null;
 217
 218         var text = this.xmlhttp.responseText;
 219         if(text == "" || text == " " || text == null) null;
 220
 221         var obj = JSON2js(text);
 222         if(!obj) return null;
 223
 224         if( obj.status != 200 ) {
 225                 if(!isXUL()) {
 226                         alert("A Server Error Occured.  Debug information follows:\n" +
 227                                 "Status: " + obj.status + '\n' + obj.debug + '\n'
 228                                 + 'Payload: ' + js2JSON(obj.payload) + '\n');
 229                 } else {
 230                         dump('Remote Request Error:' +
 231                                         '\ncode = '             + obj.status +
 232                                         '\ndebug: '             + obj.debug +
 233                                         '\npayload: '   + js2JSON(obj.payload));
 234                         throw obj;
 235                 }
 236         }
 237
 238         var payload = obj.payload;
 239         if(!payload || payload.length == 0) return null;
 240         payload = (payload.length == 1) ? payload[0] : payload;
 241
 242         if(payload.__isfieldmapper && payload.classname == "perm_ex") {
 243                 if(!isXUL()) alert(payload.err_msg());
 244                 throw payload;
 245         }
 246
 247         return payload;
 248 }
 249
 250 /* adds a new parameter to the request */
 251 RemoteRequest.prototype.addParam = function(param) {
 252         var string = encodeURIComponent(js2JSON(param));
 253         this.param_string += "&param=" + string;
 254 }
 255