cql.js

   1 function indent(n) {
   2     var s = "";
   3     for (var i = 0; i < n; i++)
   4         s = s + " ";
   5     return s;
   6 }
   7 // CQLModifier
   8 var CQLModifier = function () {
   9     this.name = null;
  10     this.relation = null;
  11     this.value = null;
  12 }
  13
  14 CQLModifier.prototype = {
  15     toXCQL: function (n) {
  16         var s = indent(n+1) + "<modifier>\n";
  17         s = s + indent(n+2) + "<name>" + this.name + "</name>\n";
  18         if (this.relation != null)
  19             s = s + indent(n+2)
  20                 + "<relation>" + this.relation + "</relation>\n";
  21         if (this.value != null)
  22             s = s + indent(n+2)
  23                 + "<value>" + this.value +"</value>\n";
  24         s = s + indent(n+1) + "</modifier>\n";
  25         return s;
  26     }
  27 }
  28 // CQLSearchClause
  29 var CQLSearchClause = function (field, fielduri, relation, relationuri,
  30                                 modifiers, term) {
  31     this.field = field;
  32     this.fielduri = fielduri;
  33     this.relation = relation;
  34     this.relationuri = relationuri;
  35     this.modifiers = modifiers;
  36     this.term = term;
  37 }
  38
  39 CQLSearchClause.prototype = {
  40     toXCQL: function (n) {
  41         var s = indent(n) + "<searchClause>\n";
  42         if (this.fielduri.length > 0)
  43         {
  44             s = s + indent(n+1) + "<prefixes>\n" +
  45                 indent(n+2) + "<prefix>\n" +
  46                 indent(n+3) + "<identifier>" + this.fielduri +
  47                 "</identifier>\n" +
  48                 indent(n+2) + "</prefix>\n" +
  49                 indent(n+1) + "</prefixes>\n";
  50         }
  51         s = s + indent(n+1) + "<index>" + this.field + "</index>\n";
  52         s = s + indent(n+1) + "<relation>\n";
  53         if (this.relationuri.length > 0) {
  54             s = s + indent(n+2) +
  55                 "<identifier>" + this.relationuri + "</identifier>\n";
  56         }
  57         s = s + indent(n+2) + "<value>" + this.relation + "</value>\n";
  58         if (this.modifiers.length > 0) {
  59             s = s + indent(n+2) + "<modifiers>\n";
  60             for (var i = 0; i < this.modifiers.length; i++)
  61                 s = s + this.modifiers[i].toXCQL(n+2);
  62             s = s + indent(n+2) + "</modifiers>\n";
  63         }
  64         s = s + indent(n+1) + "</relation>\n";
  65         s = s + indent(n+1) + "<term>" + this.term + "</term>\n";
  66         s = s + indent(n) + "</searchClause>\n";
  67         return s;
  68     }
  69 }
  70 // CQLBoolean
  71 var CQLBoolean = function() {
  72     this.op = null;
  73     this.modifiers = null;
  74     this.left = null;
  75     this.right = null;
  76 }
  77
  78 CQLBoolean.prototype = {
  79     toXCQL: function (n) {
  80         var s = indent(n) + "<triple>\n";
  81         s = s + indent(n+1) + "<boolean>\n" +
  82             indent(n+2) + "<value>" + this.op + "</value>\n";
  83         if (this.modifiers.length > 0) {
  84             s = s + indent(n+2) + "<modifiers>\n";
  85             for (var i = 0; i < this.modifiers.length; i++)
  86                 s = s + this.modifiers[i].toXCQL(n+2);
  87             s = s + indent(n+2) + "</modifiers>\n";
  88         }
  89         s = s + indent(n+1) + "</boolean>\n";
  90         s = s + indent(n+1) + "<leftOperand>\n" +
  91             this.left.toXCQL(n+2) + indent(n+1) + "</leftOperand>\n";
  92
  93         s = s + indent(n+1) + "<rightOperand>\n" +
  94             this.right.toXCQL(n+2) + indent(n+1) + "</rightOperand>\n";
  95         s = s + indent(n) + "</triple>\n";
  96         return s;
  97     }
  98 }
  99 // CQLParser
 100 var CQLParser = function () {
 101     this.qi = null;
 102     this.ql = null;
 103     this.qs = null;
 104     this.look = null;
 105     this.lval = null;
 106     this.val = null;
 107     this.prefixes = new Object();
 108     this.tree = null;
 109 }
 110
 111 CQLParser.prototype = {
 112     parse: function (query) {
 113         if (!query)
 114             throw new Error("The query to be parsed cannot be empty");
 115
 116         this.qs = query;
 117         this.ql = this.qs.length;
 118         this.qi = 0;
 119         this._move();
 120         this.tree = this._parseQuery("cql.serverChoice", "scr", new Array());
 121         if (this.look != "")
 122             throw new Error("EOF expected");
 123     },
 124     toXCQL: function () {
 125         return this.tree.toXCQL();
 126     },
 127     _parseQuery: function(field, relation, modifiers) {
 128         var left = this._parseSearchClause(field, relation, modifiers);
 129         while (this.look == "s" && (
 130                     this.lval == "and" ||
 131                     this.lval == "or" ||
 132                     this.lval == "not" ||
 133                     this.lval == "prox")) {
 134             var b = new CQLBoolean();
 135             b.op = this.lval;
 136             this._move();
 137             b.modifiers = this._parseModifiers();
 138             b.left = left;
 139             b.right = this._parseSearchClause(field, relation, modifiers);
 140             left = b;
 141         }
 142         return left;
 143     },
 144     _parseModifiers: function() {
 145         var ar = new Array();
 146         while (this.look == "/") {
 147             this._move();
 148             if (this.look != "s" && this.look != "q")
 149                 throw new Error("Invalid modifier.")
 150
 151             var name = this.lval;
 152             this._move();
 153             if (this.look.length > 0
 154                 && this._strchr("<>=", this.look.charAt(0))) {
 155                 var rel = this.look;
 156                 this._move();
 157                 if (this.look != "s" && this.look != "q")
 158                     throw new Error("Invalid relation within the modifier.");
 159
 160                 var m = new CQLModifier();
 161                 m.name = name;
 162                 m.relation = rel;
 163                 m.value = this.val;
 164                 ar.push(m);
 165                 this._move();
 166             } else {
 167                 var m = new CQLModifier();
 168                 m.name = name;
 169                 m.relation = "";
 170                 m.value = "";
 171                 ar.push(m);
 172             }
 173         }
 174         return ar;
 175     },
 176     _parseSearchClause: function(field, relation, modifiers) {
 177         if (this.look == "(") {
 178             this._move();
 179             var b = this._parseQuery(field, relation, modifiers);
 180             if (this.look == ")")
 181                 this._move();
 182             else
 183                 throw new Error("Missing closing parenthesis.");
 184
 185             return b;
 186         } else if (this.look == "s" || this.look == "q") {
 187             var first = this.val;   // dont know if field or term yet
 188             this._move();
 189             if (this.look == "q" ||
 190                     (this.look == "s" &&
 191                      this.lval != "and" &&
 192                      this.lval != "or" &&
 193                      this.lval != "not" &&
 194                      this.lval != "prox")) {
 195                 var rel = this.val;    // string relation
 196                 this._move();
 197                 return this._parseSearchClause(first, rel,
 198                                                this._parseModifiers());
 199             } else if (this.look.length > 0
 200                        && this._strchr("<>=", this.look.charAt(0))) {
 201                 var rel = this.look;   // other relation <, = ,etc
 202                 this._move();
 203                 return this._parseSearchClause(first, rel,
 204                                                this._parseModifiers());
 205             } else {
 206                 // it's a search term
 207                 var pos = field.indexOf('.');
 208                 var pre = "";
 209                 if (pos != -1)
 210                     pre = field.substring(0, pos);
 211
 212                 var uri = this._lookupPrefix(pre);
 213                 if (uri.length > 0)
 214                     field = field.substring(pos+1);
 215
 216                 pos = relation.indexOf('.');
 217                 if (pos == -1)
 218                     pre = "cql";
 219                 else
 220                     pre = relation.substring(0, pos);
 221
 222                 var reluri = this._lookupPrefix(pre);
 223                 if (reluri.Length > 0)
 224                     relation = relation.Substring(pos+1);
 225
 226                 var sc = new CQLSearchClause(field,
 227                         uri,
 228                         relation,
 229                         reluri,
 230                         modifiers,
 231                         first);
 232                 return sc;
 233             }
 234         // prefixes
 235         } else if (this.look == ">") {
 236             this._move();
 237             if (this.look != "s" && this.look != "q")
 238                 throw new Error("Expecting string or a quoted expression.");
 239
 240             var first = this.lval;
 241             this._move();
 242             if (this.look == "=")
 243             {
 244                 this._move();
 245                 if (this.look != "s" && this.look != "q")
 246                     throw new Error("Expecting string or a quoted expression.");
 247
 248                 this._addPrefix(first, this.lval);
 249                 this._move();
 250                 return this._parseQuery(field, relation, modifiers);
 251             } else {
 252                 this._addPrefix("default", first);
 253                 return this._parseQuery(field, relation, modifiers);
 254             }
 255         } else {
 256             throw new Error("Invalid search clause.");
 257         }
 258
 259     },
 260     _move: function () {
 261         while (this.qi < this.ql
 262                && this._strchr(" \t\r\n", this.qs.charAt(this.qi)))
 263             this.qi++;
 264         if (this.qi == this.ql) {
 265             this.look = "";
 266             return;
 267         }
 268         var c = this.qs.charAt(this.qi);
 269         if (this._strchr("()/", c)) {
 270             this.look = c;
 271             this.qi++;
 272         } else if (this._strchr("<>=", c)) {
 273             this.look = c;
 274             this.qi++;
 275             while (this.qi < this.ql
 276                    && this._strchr("<>=", this.qs.charAt(this.qi))) {
 277                 this.look = this.look + this.qs.charAt(this.qi);
 278                 this.qi++;
 279             }
 280         } else if (this._strchr("\"'", c)) {
 281             this.look = "q";
 282             var mark = c;
 283             this.qi++;
 284             this.val = "";
 285             while (this.qi < this.ql
 286                    && this.qs.charAt(this.qi) != mark) {
 287                 if (this.qs.charAt(this.qi) == '\\'
 288                     && this.qi < this.ql-1)
 289                     this.qi++;
 290                 this.val = this.val + this.qs.charAt(this.qi);
 291                 this.qi++;
 292             }
 293             this.lval = this.val.toLowerCase();
 294             if (this.qi < this.ql)
 295                 this.qi++;
 296         } else {
 297             this.look = "s";
 298             this.val = "";
 299             while (this.qi < this.ql
 300                    && !this._strchr("()/<>= \t\r\n", this.qs.charAt(this.qi))) {
 301                 this.val = this.val + this.qs.charAt(this.qi);
 302                 this.qi++;
 303             }
 304             this.lval = this.val.toLowerCase();
 305         }
 306     },
 307     _strchr: function (s, ch) {
 308         return s.indexOf(ch) >= 0
 309     },
 310     _lookupPrefix: function(name) {
 311         return this.prefixes[name] ? this.prefixes[name] : "";
 312     },
 313     _addPrefix: function(name, value) {
 314         //overwrite existing items
 315         this.prefixes[name] = value;
 316     }
 317 }