parser.js

   1 // ER diagram description parser
   2 class ErDiags
   3 {
   4     constructor(description)
   5     {
   6         this.entities = {};
   7         this.inheritances = [];
   8         this.associations = [];
   9         this.txt2json(description);
  10         this.tables = [];
  11         // Cache SVG graphs returned by server (in addition to server cache = good perfs)
  12         this.mcdGraph = "";
  13         this.mldGraph = "";
  14         this.sqlText = "";
  15     }
  16
  17     static get TYPES()
  18     {
  19         // SQLite types without null (TODO: be more general)
  20         return ["integer","real","text","blob"];
  21     }
  22
  23     static get CARDINAL()
  24     {
  25         return {
  26             "*": "0,n",
  27             "+": "1,n",
  28             "?": "0,1",
  29             "1": "1,1"
  30         };
  31     }
  32
  33     //////////////////
  34     // PARSING STAGE 1
  35     //////////////////
  36
  37     // Parse a textual description into a json object
  38     txt2json(text)
  39     {
  40         let lines = text.split("\n");
  41         lines.push(""); //easier parsing: always empty line at the end
  42         let start = -1;
  43         for (let i=0; i < lines.length; i++)
  44         {
  45             lines[i] = lines[i].trim();
  46             // Empty line ?
  47             if (lines[i].length == 0)
  48             {
  49                 if (start >= 0) //there is some group of lines to parse
  50                 {
  51                     this.parseThing(lines, start, i);
  52                     start = -1;
  53                 }
  54             }
  55             else //not empty line: just register starting point
  56             {
  57                 if (start < 0)
  58                     start = i;
  59             }
  60         }
  61     }
  62
  63     // Parse a group of lines into entity, association, ...
  64     parseThing(lines, start, end) //start included, end excluded
  65     {
  66         switch (lines[start].charAt(0))
  67         {
  68             case '[':
  69                 // Entity = { name: { attributes, [weak] } }
  70                 let name = lines[start].match(/\w+/)[0];
  71                 let entity = { attributes: this.parseAttributes(lines, start+1, end) };
  72                 if (lines[start].charAt(1) == '[')
  73                     entity.weak = true;
  74                 this.entities[name] = entity;
  75                 break;
  76             case 'i': //inheritance (arrows)
  77                 this.inheritances = this.inheritances.concat(this.parseInheritance(lines, start+1, end));
  78                 break;
  79             case '{': //association
  80                 // Association = { [name], [attributes], [weak], entities: ArrayOf entity indices }
  81                 let relationship = { };
  82                 let nameRes = lines[start].match(/\w+/);
  83                 if (nameRes !== null)
  84                     relationship.name = nameRes[0];
  85                 if (lines[start].charAt(1) == '{')
  86                     relationship.weak = true;
  87                 this.associations.push(Object.assign({}, relationship, this.parseAssociation(lines, start+1, end)));
  88                 break;
  89         }
  90     }
  91
  92     // attributes: ArrayOf {name, [isKey], [type], [qualifiers]}
  93     parseAttributes(lines, start, end)
  94     {
  95         let attributes = [];
  96         for (let i=start; i<end; i++)
  97         {
  98             let field = { name: lines[i].match(/\w+/)[0] };
  99             if (lines[i].charAt(0) == '#')
 100                 field.isKey = true;
 101             let parenthesis = lines[i].match(/\((.+)\)/);
 102             if (parenthesis !== null)
 103             {
 104                 let sqlClues = parenthesis[1];
 105                 let qualifiers = sqlClues;
 106                 let firstWord = sqlClues.match(/\w+/)[0];
 107                 if (ErDiags.TYPES.includes(firstWord))
 108                 {
 109                     field.type = firstWord;
 110                     qualifiers = sqlClues.substring(firstWord.length).trim();
 111                 }
 112                 field.qualifiers = qualifiers;
 113             }
 114             attributes.push(field);
 115         }
 116         return attributes;
 117     }
 118
 119     // GroupOf Inheritance: { parent, children: ArrayOf entity indices }
 120     parseInheritance(lines, start, end)
 121     {
 122         let inheritance = [];
 123         for (let i=start; i<end; i++)
 124         {
 125             let lineParts = lines[i].split(" ");
 126             let children = [];
 127             for (let j=1; j<lineParts.length; j++)
 128                 children.push(lineParts[j]);
 129             inheritance.push({ parent:lineParts[0], children: children });
 130         }
 131         return inheritance;
 132     }
 133
 134     // Association (parsed here): { entities: ArrayOf entity names + cardinality, [attributes: ArrayOf {name, [isKey], [type], [qualifiers]}] }
 135     parseAssociation(lines, start, end)
 136     {
 137         let assoce = { };
 138         let entities = [];
 139         let i = start;
 140         while (i < end)
 141         {
 142             if (lines[i].charAt(0) == '-')
 143             {
 144                 assoce.attributes = this.parseAttributes(lines, i+1, end);
 145                 break;
 146             }
 147             else
 148             {
 149                 // Read entity name + cardinality
 150                 let lineParts = lines[i].split(" ");
 151                 entities.push({ name:lineParts[0], card:lineParts[1] });
 152             }
 153             i++;
 154         }
 155         assoce.entities = entities;
 156         return assoce;
 157     }
 158
 159     //////////////////
 160     // PARSING STAGE 2
 161     //////////////////
 162
 163     static AjaxGet(dotInput, callback)
 164     {
 165         let xhr = new XMLHttpRequest();
 166         xhr.onreadystatechange = function() {
 167             if (this.readyState == 4 && this.status == 200)
 168                 callback(this.responseText);
 169         };
 170         xhr.open("GET", "scripts/getGraphSvg.php?dot=" + encodeURIComponent(dotInput), true);
 171         xhr.send();
 172     }
 173
 174     // "Modèle conceptuel des données". TODO: option for graph size
 175     drawMcd(id, mcdStyle) //mcdStyle: bubble, or compact
 176     {
 177         let element = document.getElementById(id);
 178         mcdStyle = mcdStyle || "compact";
 179         if (this.mcdGraph.length > 0)
 180         {
 181             element.innerHTML = this.mcdGraph;
 182             return;
 183         }
 184         // Build dot graph input
 185         let mcdDot = 'graph {\n';
 186         // Nodes:
 187         Object.keys(this.entities).forEach( name => {
 188             if (mcdStyle == "bubble")
 189             {
 190                 mcdDot += name + '[shape=rectangle, label="' + name + '"';
 191                 if (this.entities[name].weak)
 192                     mcdDot += ', peripheries=2';
 193                 mcdDot += '];\n';
 194                 if (!!this.entities[name].attributes)
 195                 {
 196                     this.entities[name].attributes.forEach( a => {
 197                         let label = (a.isKey ? '#' : '') + a.name;
 198                         mcdDot += name + '_' + a.name + '[shape=ellipse, label="' + label + '"];\n';
 199                         mcdDot += name + '_' + a.name + ' -- ' + name + ';\n';
 200                     });
 201                 }
 202             }
 203             else
 204             {
 205                 mcdDot += name + '[shape=plaintext, label=<';
 206                 if (this.entities[name].weak)
 207                 {
 208                     mcdDot += '<table port="name" BORDER="1" ALIGN="LEFT" CELLPADDING="0" CELLSPACING="3" CELLBORDER="0">' +
 209                         '<tr><td><table BORDER="1" ALIGN="LEFT" CELLPADDING="5" CELLSPACING="0">\n';
 210                 }
 211                 else
 212                     mcdDot += '<table port="name" BORDER="1" ALIGN="LEFT" CELLPADDING="5" CELLSPACING="0">\n';
 213                 mcdDot += '<tr><td BGCOLOR="#ae7d4e" BORDER="0"><font COLOR="#FFFFFF">' + name + '</font></td></tr>\n';
 214                 if (!!this.entities[name].attributes)
 215                 {
 216                     this.entities[name].attributes.forEach( a => {
 217                         let label = (a.isKey ? '<u>' : '') + a.name + (a.isKey ? '</u>' : '');
 218                         mcdDot += '<tr><td BGCOLOR="#FFFFFF" BORDER="0" ALIGN="LEFT"><font COLOR="#000000" >' + label + '</font></td></tr>\n';
 219                     });
 220                 }
 221                 mcdDot += '</table>';
 222                 if (this.entities[name].weak)
 223                     mcdDot += '</td></tr></table>';
 224                 mcdDot += '>];\n';
 225             }
 226         });
 227         // Inheritances:
 228         this.inheritances.forEach( i => {
 229             i.children.forEach( c => {
 230                 mcdDot += c + ':name -- ' + i.parent + ':name [len="1.00", dir="forward", arrowhead="vee", style="dashed"];\n';
 231             });
 232         });
 233         // Relationships:
 234         let assoceCounter = 0;
 235         this.associations.forEach( a => {
 236             let name = !!a.name && a.name.length > 0
 237                 ? a.name
 238                 : '_assoce' + assoceCounter++;
 239             mcdDot += name + '[shape="diamond", style="filled", color="lightgrey", label="' + (!!a.name ? a.name : '') + '"';
 240             if (a.weak)
 241                 mcdDot += ', peripheries=2';
 242             mcdDot += '];\n';
 243             a.entities.forEach( e => {
 244                 mcdDot += e.name + ':name -- ' + name + '[len="1.00", label="' + ErDiags.CARDINAL[e.card] + '"];\n';
 245             });
 246             if (!!a.attributes)
 247             {
 248                 a.attributes.forEach( attr => {
 249                     let label = (attr.isKey ? '#' : '') + attr.name;
 250                     mcdDot += name + '_' + attr.name + '[len="1.00", shape=ellipse, label="' + label + '"];\n';
 251                     mcdDot += name + '_' + attr.name + ' -- ' + name + ';\n';
 252                 });
 253             }
 254         });
 255         mcdDot += '}';
 256         //console.log(mcdDot);
 257         ErDiags.AjaxGet(mcdDot, graphSvg => {
 258             this.mcdGraph = graphSvg;
 259             element.innerHTML = graphSvg;
 260         })
 261     }
 262
 263     // "Modèle logique des données"
 264     drawMld(id)
 265     {
 266         let element = document.getElementById(id);
 267         if (this.mldGraph.length > 0)
 268         {
 269             element.innerHTML = this.mcdGraph;
 270             return;
 271         }
 272         // Build dot graph input
 273         let mldDot = 'graph {\n';
 274         // Nodes:
 275         Object.keys(this.entities).forEach( name => {
 276             //mld. ... --> devient table
 277             // mldDot = ...
 278         });
 279         // Relationships:
 280         this.associations.forEach( a => {
 281             a.entities.forEach( e => { // e.card e.name ...
 282                 // Pass 1 : entites deviennent tables
 283                 // Pass 2 : sur les assoces
 284                 // multi-arite : sub-loop si 0,1 ou 1,1 : aspiré comme attribut de l'association (phase 1)
 285                 // ensuite, que du 0,n ou 1,n : si == 1, OK une table
 286                 // si 2 ou + : n tables + 1 pour l'assoce, avec attrs clés étrangères
 287                 // clé étrangère NOT NULL si 1,1
 288             });
 289         });
 290         // this.graphMld = ...
 291     }
 292
 293     fillSql(id)
 294     {
 295         let element = document.getElementById(id);
 296         if (this.sqlText.length > 0)
 297         {
 298             element.innerHTML = this.sqlText;
 299             return;
 300         }
 301         //UNIMPLEMENTED (should be straightforward from MLD)
 302     }
 303 }