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 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.abort();
  44                 r.xmlhttp = null;
  45         }
  46
  47         r.callback                              = null;
  48         r.userdata                              = null;
  49         _allrequests[r.id]      = null;
  50 }
  51
  52 /* ----------------------------------------------------------------------- */
  53 /* Request object */
  54 function RemoteRequest( service, method ) {
  55
  56
  57         this.service    = service;
  58         this.method             = method;
  59         this.xmlhttp    = false;
  60         this.name               = null;
  61         this.sendCount = 0;
  62
  63         this.type               = "POST"; /* default */
  64         this.id                 = service + method + Math.random();
  65         this.cancelled = false;
  66
  67         _allrequests[this.id] = this;
  68
  69         var i = 2;
  70         this.params = "";
  71
  72         while(i < arguments.length) {
  73                 var object = js2JSON(arguments[i++]);
  74                 this.params += "&param=" + encodeURIComponent(object);
  75         }
  76
  77         if(!this.params) { this.params = ""; }
  78         this.param_string = "service=" + service + "&method=" + method + this.params;
  79         if( this.buildXMLRequest() == null ) alert("Browser is not supported!");
  80 }
  81
  82 RemoteRequest.prototype.abort = function() {
  83         if( this.xmlhttp ) this.xmlhttp.abort();
  84 }
  85
  86 /* constructs our XMLHTTPRequest object */
  87 RemoteRequest.prototype.buildXMLRequest = function() {
  88
  89         var x;
  90         try {
  91                 x = new ActiveXObject("Msxml2.XMLHTTP");
  92         } catch (e) {
  93                 try {
  94                         x = new ActiveXObject("Microsoft.XMLHTTP");
  95                 } catch (E) {
  96                         x = false;
  97                 }
  98         }
  99
 100         if (!x && typeof XMLHttpRequest!='undefined') x = new XMLHttpRequest();
 101
 102         if(!x) {
 103                 alert("NEEDS NEWER JAVASCRIPT for XMLHTTPRequest()");
 104                 return null;
 105         }
 106
 107         this.xmlhttp = x;
 108         return true;
 109 }
 110
 111
 112 function _remoteRequestCallback(id) {
 113
 114         var object = _allrequests[id];
 115         if(object.cancelled) return;
 116
 117         if( object.xmlhttp.readyState == 4 ) {
 118                 try {
 119                         object.callback(object);
 120                 } catch(E) {
 121
 122                         /* if we receive a communication error, retry the request up
 123                                 to XML_HTTP_MAX_TRIES attempts */
 124                         if( E && E.classname == "EXCommunication" ) {
 125
 126                                 //try { dump('Communication Error: ' + E ); } catch(e){}
 127                                 alert('Debug:  Communication Error: ' + E );
 128
 129                                 if(object.sendCount >= XML_HTTP_MAX_TRIES ) {
 130                                         if(isXUL()) throw object;
 131                                          else alert("Arrrgghh, Matey! Error communicating:\n" + E  + "\n" + object.param_string);
 132                                 } else {
 133                                         object.buildXMLRequest();
 134                                         object.send();
 135                                         return;
 136                                 }
 137                         } else { throw E; }
 138
 139                 } finally {
 140                         destroyRequest(object);
 141                         object = null;
 142                 }
 143         }
 144 }
 145
 146
 147 /* define the callback we use when this request has received
 148         all of its data */
 149 RemoteRequest.prototype.setCompleteCallback = function(callback) {
 150         if(this.cancelled) return;
 151         this.callback = callback;
 152         var id = this.id;
 153         this.xmlhttp.onreadystatechange = function() { _remoteRequestCallback(id); }
 154 }
 155
 156
 157 /* http by default.  This makes it https. *ONLY works when
 158         embedded in a XUL app. */
 159 RemoteRequest.prototype.setSecure = function(bool) {
 160         this.secure = bool;
 161 }
 162
 163 RemoteRequest.prototype.send = function(blocking) {
 164
 165         if(this.cancelled) return;
 166
 167         /* determine the xmlhttp server dynamically */
 168         var url = location.protocol + "//" + location.host + "/" + XML_HTTP_GATEWAY;
 169
 170         if(isXUL()) {
 171                 if(this.secure || url.match(/^https:/) )
 172                         url =   "https://" + XML_HTTP_SERVER + "/" + XML_HTTP_GATEWAY;
 173                 else
 174                         url =   "http://" + XML_HTTP_SERVER + "/" + XML_HTTP_GATEWAY;
 175         }
 176
 177         var data = null;
 178         if( this.type == 'GET' ) url +=  "?" + this.param_string;
 179
 180         try {
 181
 182                 if(blocking) this.xmlhttp.open(this.type, url, false);
 183                 else this.xmlhttp.open(this.type, url, true);
 184
 185         } catch(E) {
 186                 alert("Fatal error opening XMLHTTPRequest for URL:\n" + url + '\n');
 187                 return;
 188         }
 189
 190
 191         if( this.type == 'POST' ) {
 192                 data = this.param_string;
 193                 this.xmlhttp.setRequestHeader('Content-Type',
 194                                 'application/x-www-form-urlencoded');
 195         }
 196
 197         try{ this.xmlhttp.send( data ); } catch(e){}
 198
 199         this.sendCount += 1;
 200         return this;
 201 }
 202
 203 /* returns the actual response text from the request */
 204 RemoteRequest.prototype.getText = function() {
 205         return this.xmlhttp.responseText;
 206 }
 207
 208 RemoteRequest.prototype.isReady = function() {
 209         return this.xmlhttp.readyState == 4;
 210 }
 211
 212
 213 /* returns the JSON->js result object  */
 214 RemoteRequest.prototype.getResultObject = function() {
 215
 216         if(this.cancelled) return null;
 217         if(!this.xmlhttp) return null;
 218
 219         var text = this.xmlhttp.responseText;
 220         if(text == "" || text == " " || text == null) null;
 221
 222         var obj = JSON2js(text);
 223         if(!obj) return null;
 224
 225         if( obj.status != 200 ) {
 226                 if(!isXUL()) {
 227                         alert("A Server Error Occured.  Debug information follows:\n" +
 228                                 "Status: " + obj.status + '\n' + obj.debug + '\n'
 229                                 + 'Payload: ' + js2JSON(obj.payload) + '\n');
 230                 } else {
 231                         dump('Remote Request Error:' +
 232                                         '\ncode = '             + obj.status +
 233                                         '\ndebug: '             + obj.debug +
 234                                         '\npayload: '   + js2JSON(obj.payload));
 235                         throw obj;
 236                 }
 237         }
 238
 239         var payload = obj.payload;
 240         if(!payload || payload.length == 0) return null;
 241         payload = (payload.length == 1) ? payload[0] : payload;
 242
 243         if(payload.__isfieldmapper && payload.classname == "perm_ex") {
 244                 if(!isXUL()) alert(payload.err_msg());
 245                 throw payload;
 246         }
 247
 248         return payload;
 249 }
 250
 251 /* adds a new parameter to the request */
 252 RemoteRequest.prototype.addParam = function(param) {
 253         var string = encodeURIComponent(js2JSON(param));
 254         this.param_string += "&param=" + string;
 255 }
 256