memdb/memdb.js

   1 // 知識表現のデータベース
   2 // php経由でMySQLデータベースに同期する機能と
   3 // データへのアクセスを提供する
   4
   5 function MemoryDB(syncPHPURL){
   6         // 全データ
   7         this.root = new Array();
   8         //
   9         this.nodeList = new Array();
  10         //
  11         this.syncPHPURL = syncPHPURL;
  12         this.isEnabledNetDB = true;
  13         //
  14         this.callback_refreshedNode = null;     // function(nodeinstance){};
  15 }
  16 MemoryDB.prototype = {
  17         UUID_Null: "00000000-0000-0000-0000-000000000000",
  18         UUID_NodeType_DecimalNumber: "e3346fd4-ac17-41c3-b3c7-e04972e5c014",
  19         UUID_Node_MemoryDBNetworkTimestamp: "a2560a9c-dcf7-4746-ac14-347188518cf2",
  20         createRequestObject: function(){
  21                 var rq = null;
  22                 // XMLHttpRequest
  23                 try{
  24                         // XMLHttpRequest オブジェクトを作成
  25                         rq = new XMLHttpRequest();
  26                 }catch(e){}
  27                 // Internet Explorer
  28                 try{
  29                         rq = new ActiveXObject('MSXML2.XMLHTTP.6.0');
  30                 }catch(e){}
  31                 try{
  32                         rq = new ActiveXObject('MSXML2.XMLHTTP.3.0');
  33                 }catch(e){}
  34                 try{
  35                         rq = new ActiveXObject('MSXML2.XMLHTTP');
  36                 }catch(e){}
  37                 if(rq == null){
  38                         return null;
  39                 }
  40                 return rq;
  41         },
  42         requestObjectDisableCache: function(rq){
  43                 //call after open request.
  44                 //disable cache
  45                 //http://vird2002.s8.xrea.com/javascript/XMLHttpRequest.html
  46                 rq.setRequestHeader('Pragma', 'no-cache');                              // HTTP/1.0 における汎用のヘッダフィールド
  47                 rq.setRequestHeader('Cache-Control', 'no-cache');               // HTTP/1.1 におけるキャッシュ制御のヘッダフィールド
  48                 rq.setRequestHeader('If-Modified-Since', 'Thu, 01 Jun 1970 00:00:00 GMT');
  49         },
  50         sendRequestSync: function(mode, url, data){
  51                 //同期モード
  52                 var q = this.createRequestObject();
  53                 q.open(mode, url, false);
  54                 q.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
  55                 this.requestObjectDisableCache(q);
  56                 try {
  57                         q.send(data);
  58                 } catch(e){
  59                         console.log("sendRequestSync:Network Error.\n");
  60                         this.isEnabledNetDB = false;
  61                         return null;
  62                 }
  63                 if(q.status == 0){
  64                         console.log("ネットワークにアクセスできません。" + q.status + ":" + q.statusText);
  65                 }else if((200 <= q.status && q.status < 300) || (q.status == 304)){
  66                         var res = q.responseText;
  67                         return res;
  68                 } else{
  69                         console.log("サーバーがエラーを返しました。" + request.status + ":" + request.statusText);
  70                 }
  71                 this.isEnabledNetDB = false;
  72                 return null;
  73         },
  74         syncDB: function(){
  75                 // MySQLと同期
  76                 // 定期的に呼び出されることを想定
  77                 var r, a, d;
  78                 if(this.root.length == 0){
  79                         // 初回同期時は全て取得
  80                         r = this.sendRequestSync("GET", this.syncPHPURL + "?action=getallnode", null);
  81                 } else{
  82                         // 差分のみを取得
  83                         d = this.getNodeFromUUID(this.UUID_Node_MemoryDBNetworkTimestamp).identifier;
  84                         r = this.sendRequestSync("GET", this.syncPHPURL + "?action=getnodemod&t=" + d, null);
  85                 }
  86                 a = r.split("\n");
  87                 for(var i = 0, iLen = a.length; i < iLen; i++){
  88                         try{
  89                                 d = eval(a[i]);
  90                         } catch(e){
  91                                 console.log(i + ": " + e + "\n");
  92                                 continue;
  93                         }
  94                         if(d === undefined){
  95                                 continue;
  96                         }
  97                         this.refreshNodeInternal(d[2], d[1], d[0]);
  98                 }
  99                 console.log(this.root);
 100         },
 101         refreshNode: function(ident, tid, nid){
 102                 // 該当タグのデータを書き換え、もしくは新規作成する。
 103                 // 可能であればネットワークに反映する
 104                 // nid(nodeid)は省略可能で、省略時は新たなUUIDが自動的に付与される
 105                 // tid(typeid)も省略可能で、省略時はNullUUIDが付与される。
 106                 // identはnullもしくは空文字でもかまわない。
 107                 // 戻り値はMemoryDBNodeTagインスタンス
 108                 // エラー発生時はundefinedを返す。
 109                 this.refreshNodeInternal(ident, tid, nid, true);
 110         },
 111         refreshNodeInternal: function(ident, tid, nid, enableSync){
 112                 // 基本的にローカルデータのみ変更
 113                 // enableSync == trueでネットワーク同期する
 114                 var t, s, r;
 115                 if(!tid){
 116                         tid = this.UUID_Null;
 117                 }
 118                 if(!nid){
 119                         nid = this.createUUID();
 120                 }
 121                 // 存在確認
 122                 t = this.getNodeFromUUID(nid);
 123                 if(t){
 124                         // 変更
 125                         return undefined;
 126                 } else{
 127                         // 新規作成
 128                         t = new MemoryDBNodeTag(nid, tid, ident);
 129                         this.root.push(t);
 130                         this.nodeList.push(t);
 131                         if(enableSync && this.isEnabledNetDB){
 132                                 s = this.syncPHPURL + "?action=addnode";
 133                                 s += "&nid=" + encodeURIComponent(nid);
 134                                 s += "&tid=" + encodeURIComponent(tid);
 135                                 s += "&ident=" + encodeURIComponent(ident);
 136                                 r = this.sendRequestSync("GET", s, null);
 137                                 console.log(r);
 138                         }
 139                 }
 140                 if(this.callback_refreshedNode){
 141                         this.callback_refreshedNode(t);
 142                 }
 143         },
 144         createUUID: function(){
 145                 var f = this.createUUIDSub;
 146                 return (f() + f() + "-" + f() + "-" + f() + "-" + f() + "-" + f() + f() + f());
 147         },
 148         createUUIDSub: function(){
 149                 return (((1 + Math.random()) * 0x10000) | 0).toString(16).toLowerCase().substring(1);
 150         },
 151         getNodeFromUUID: function(nodeid){
 152                 return this.nodeList.isIncluded(nodeid, function(a, b){ return a.nodeid == b; });
 153         },
 154 }
 155
 156 function MemoryDBNodeTag(nodeid, typeid, identifier){
 157         this.nodeid = nodeid;
 158         this.typeid = typeid;
 159         this.identifier = identifier;
 160         //
 161 }
 162 MemoryDBNodeTag.prototype = {
 163
 164 }
 165
 166 function MemoryDBEdgeTag(typeUUIDStr){
 167         this.uuid = null;
 168 }
 169 MemoryDBEdgeTag.prototype = {
 170
 171 }