lib/dojo/OpenAjax.js

   1 /*******************************************************************************
   2  * OpenAjax.js
   3  *
   4  * Reference implementation of the OpenAjax Hub, as specified by OpenAjax Alliance.
   5  * Specification is under development at:
   6  *
   7  *   http://www.openajax.org/member/wiki/OpenAjax_Hub_Specification
   8  *
   9  * Copyright 2006-2007 OpenAjax Alliance
  10  *
  11  * Licensed under the Apache License, Version 2.0 (the "License"); you may not
  12  * use this file except in compliance with the License. You may obtain a copy
  13  * of the License at http://www.apache.org/licenses/LICENSE-2.0 . Unless
  14  * required by applicable law or agreed to in writing, software distributed
  15  * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
  16  * CONDITIONS OF ANY KIND, either express or implied. See the License for the
  17  * specific language governing permissions and limitations under the License.
  18  *
  19  ******************************************************************************/
  20
  21 // prevent re-definition of the OpenAjax object
  22 if(!window["OpenAjax"]){
  23         OpenAjax = new function(){
  24                 // summary: the OpenAjax hub
  25                 // description: see http://www.openajax.org/member/wiki/OpenAjax_Hub_Specification
  26
  27                 var t = true;
  28                 var f = false;
  29                 var g = window;
  30                 var libs;
  31                 var ooh = "org.openajax.hub.";
  32
  33                 var h = {};
  34                 this.hub = h;
  35                 h.implementer = "http://openajax.org";
  36                 h.implVersion = "0.6";
  37                 h.specVersion = "0.6";
  38                 h.implExtraData = {};
  39                 var libs = {};
  40                 h.libraries = libs;
  41
  42                 h.registerLibrary = function(prefix, nsURL, version, extra){
  43                         libs[prefix] = {
  44                                 prefix: prefix,
  45                                 namespaceURI: nsURL,
  46                                 version: version,
  47                                 extraData: extra
  48                         };
  49                         this.publish(ooh+"registerLibrary", libs[prefix]);
  50                 };
  51                 h.unregisterLibrary = function(prefix){
  52                         this.publish(ooh+"unregisterLibrary", libs[prefix]);
  53                         delete libs[prefix];
  54                 };
  55
  56                 h._subscriptions = { c:{}, s:[] };
  57                 h._cleanup = [];
  58                 h._subIndex = 0;
  59                 h._pubDepth = 0;
  60
  61                 h.subscribe = function(name, callback, scope, subscriberData, filter){
  62                         if(!scope){
  63                                 scope = window;
  64                         }
  65                         var handle = name + "." + this._subIndex;
  66                         var sub = { scope: scope, cb: callback, fcb: filter, data: subscriberData, sid: this._subIndex++, hdl: handle };
  67                         var path = name.split(".");
  68                         this._subscribe(this._subscriptions, path, 0, sub);
  69                         return handle;
  70                 };
  71
  72                 h.publish = function(name, message){
  73                         var path = name.split(".");
  74                         this._pubDepth++;
  75                         this._publish(this._subscriptions, path, 0, name, message);
  76                         this._pubDepth--;
  77                         if((this._cleanup.length > 0) && (this._pubDepth == 0)){
  78                                 for(var i = 0; i < this._cleanup.length; i++){
  79                                         this.unsubscribe(this._cleanup[i].hdl);
  80                                 }
  81                                 delete(this._cleanup);
  82                                 this._cleanup = [];
  83                         }
  84                 };
  85
  86                 h.unsubscribe = function(sub){
  87                         var path = sub.split(".");
  88                         var sid = path.pop();
  89                         this._unsubscribe(this._subscriptions, path, 0, sid);
  90                 };
  91
  92                 h._subscribe = function(tree, path, index, sub){
  93                         var token = path[index];
  94                         if(index == path.length){
  95                                 tree.s.push(sub);
  96                         }else{
  97                                 if(typeof tree.c == "undefined"){
  98                                         tree.c = {};
  99                                 }
 100                                 if(typeof tree.c[token] == "undefined"){
 101                                         tree.c[token] = { c: {}, s: [] };
 102                                         this._subscribe(tree.c[token], path, index + 1, sub);
 103                                 }else{
 104                                         this._subscribe(tree.c[token], path, index + 1, sub);
 105                                 }
 106                         }
 107                 };
 108
 109                 h._publish = function(tree, path, index, name, msg){
 110                         if(typeof tree != "undefined"){
 111                                 var node;
 112                                 if(index == path.length){
 113                                         node = tree;
 114                                 }else{
 115                                         this._publish(tree.c[path[index]], path, index + 1, name, msg);
 116                                         this._publish(tree.c["*"], path, index + 1, name, msg);
 117                                         node = tree.c["**"];
 118                                 }
 119                                 if(typeof node != "undefined"){
 120                                         var callbacks = node.s;
 121                                         var max = callbacks.length;
 122                                         for(var i = 0; i < max; i++){
 123                                                 if(callbacks[i].cb){
 124                                                         var sc = callbacks[i].scope;
 125                                                         var cb = callbacks[i].cb;
 126                                                         var fcb = callbacks[i].fcb;
 127                                                         var d = callbacks[i].data;
 128                                                         if(typeof cb == "string"){
 129                                                                 // get a function object
 130                                                                 cb = sc[cb];
 131                                                         }
 132                                                         if(typeof fcb == "string"){
 133                                                                 // get a function object
 134                                                                 fcb = sc[fcb];
 135                                                         }
 136                                                         if((!fcb) ||
 137                                                                 (fcb.call(sc, name, msg, d))){
 138                                                                 cb.call(sc, name, msg, d);
 139                                                         }
 140                                                 }
 141                                         }
 142                                 }
 143                         }
 144                 };
 145
 146                 h._unsubscribe = function(tree, path, index, sid){
 147                         if(typeof tree != "undefined"){
 148                                 if(index < path.length){
 149                                         var childNode = tree.c[path[index]];
 150                                         this._unsubscribe(childNode, path, index + 1, sid);
 151                                         if(childNode.s.length == 0){
 152                                                 for(var x in childNode.c)
 153                                                         return;
 154                                                 delete tree.c[path[index]];
 155                                         }
 156                                         return;
 157                                 }
 158                                 else{
 159                                         var callbacks = tree.s;
 160                                         var max = callbacks.length;
 161                                         for(var i = 0; i < max; i++)
 162                                                 if(sid == callbacks[i].sid){
 163                                                         if(this._pubDepth > 0){
 164                                                                 callbacks[i].cb = null;
 165                                                                 this._cleanup.push(callbacks[i]);
 166                                                         }
 167                                                         else
 168                                                                 callbacks.splice(i, 1);
 169                                                         return;
 170                                                 }
 171                                 }
 172                         }
 173                 };
 174                 // The following function is provided for automatic testing purposes.
 175                 // It is not expected to be deployed in run-time OpenAjax Hub implementations.
 176                 h.reinit = function()
 177                 {
 178                         for (var lib in OpenAjax.hub.libraries) {
 179                                 delete OpenAjax.hub.libraries[lib];
 180                         }
 181                         OpenAjax.hub.registerLibrary("OpenAjax", "http://openajax.org/hub", "0.6", {});
 182
 183                         delete OpenAjax._subscriptions;
 184                         OpenAjax._subscriptions = {c:{},s:[]};
 185                         delete OpenAjax._cleanup;
 186                         OpenAjax._cleanup = [];
 187                         OpenAjax._subIndex = 0;
 188                         OpenAjax._pubDepth = 0;
 189                 }
 190         };
 191         // Register the OpenAjax Hub itself as a library.
 192         OpenAjax.hub.registerLibrary("OpenAjax", "http://openajax.org/hub", "0.6", {});
 193
 194 }