First draft of drawMld() + fillSql()
authorBenjamin Auder <benjamin.auder@somewhere>
Fri, 2 Feb 2018 17:10:09 +0000 (18:10 +0100)
committerBenjamin Auder <benjamin.auder@somewhere>
Fri, 2 Feb 2018 17:10:09 +0000 (18:10 +0100)
README.md
parser.js

index acf706e..b39f8a7 100644 (file)
--- a/README.md
+++ b/README.md
@@ -5,10 +5,9 @@ Inspired by [this repository](https://code.google.com/archive/p/merisier/).
 This parser reads ER diagrams definition files, and produces two types of diagrams + SQL code.
 [Graphviz](https://www.graphviz.org/) is used on server side to translate parsed graph descriptions into SVG objects.
 
-*Note:* at the moment only the conceptual graph is implemented, and no comments are allowed in textual descriptions.
-At least the former is planned, and also probably a way to indicate relative identifiers, and maybe links between relationships.
+*TODO list:* functional integrity constraints (CIF), inter-relations constraints (or, and, xor...), inheritance with the right symbol (triangle).
 
-*Note bis:* temporary dependency to [underscore](http://underscorejs.org/); good library but used so far only for its shuffle() method.
+*Note:* temporary dependency to [underscore](http://underscorejs.org/); good library but used so far only for its shuffle() method.
 
 -----
 
@@ -37,6 +36,8 @@ Cardinality dictionary:
  * 1 = 1..1
  * ? = 0..1
 
+Special cardinalities are also available to indicate relative identification: `?R` and `1R`.
+
 To mark a weak entity, just surround its name by extra-brackets
 
        [[WeakEntity]]
index 0d52ee0..f718f31 100644 (file)
--- a/parser.js
+++ b/parser.js
@@ -6,19 +6,15 @@ class ErDiags
                this.entities = { };
                this.inheritances = [ ];
                this.associations = [ ];
-               this.txt2json(description);
+               this.tables = { };
+               this.mcdParsing(description);
+               this.mldParsing();
                // Cache SVG graphs returned by server (in addition to server cache = good perfs)
                this.mcdGraph = "";
                this.mldGraph = "";
                this.sqlText = "";
        }
 
-       static get TYPES()
-       {
-               // SQLite storage classes without null
-               return ["integer","real","text","blob"];
-       }
-
        static get CARDINAL()
        {
                return {
@@ -31,12 +27,12 @@ class ErDiags
                };
        }
 
-       //////////////////
-       // PARSING STAGE 1
-       //////////////////
+       ///////////////////////////////
+       // PARSING STAGE 1: text to MCD
+       ///////////////////////////////
 
        // Parse a textual description into a json object
-       txt2json(text)
+       mcdParsing(text)
        {
                let lines = text.split("\n");
                lines.push(""); //easier parsing: always empty line at the end
@@ -108,14 +104,8 @@ class ErDiags
                        if (parenthesis !== null)
                        {
                                let sqlClues = parenthesis[1];
-                               let qualifiers = sqlClues;
-                               let firstWord = sqlClues.match(/[^\s]+/)[0];
-                               if (ErDiags.TYPES.includes(firstWord))
-                               {
-                                       field.type = firstWord;
-                                       qualifiers = sqlClues.substring(firstWord.length).trim();
-                               }
-                               field.qualifiers = qualifiers;
+                               field.type = sqlClues.match(/[^\s]+/)[0]; //type is always the first indication (mandatory)
+                               field.qualifiers = sqlClues.substring(field.type.length).trim();
                        }
                        attributes.push(field);
                }
@@ -165,9 +155,95 @@ class ErDiags
                return assoce;
        }
 
-       //////////////////
-       // PARSING STAGE 2
-       //////////////////
+       //////////////////////////////
+       // PARSING STAGE 2: MCD to MLD
+       //////////////////////////////
+
+       // From entities + relationships to tables
+       mldParsing()
+       {
+               // Pass 1: initialize tables
+               Object.keys(this.entities).forEach( name => {
+                       let newTable = [ ]; //array of fields
+                       this.entities[name].attributes.forEach( attr => {
+                               newTable.push({
+                                       name: attr.name,
+                                       type: attr.type,
+                                       isKey: attr.isKey,
+                                       qualifiers: attr.qualifiers,
+                               });
+                       });
+                       this.tables[name] = newTable;
+               });
+               // Pass 2: parse associations, add foreign keys when cardinality is 0,1 or 1,1
+               this.associations.forEach( a => {
+                       let newTableAttrs = [ ];
+                       a.entities.forEach( e => {
+                               if (['?','1'].includes(e.card[0]))
+                               {
+                                       // Foreign key apparition (for each entity in association minus current one, for each identifying attribute)
+                                       a.entities.forEach( e2 => {
+                                               if (e2.name == e.name)
+                                                       return;
+                                               e2.attributes.forEach( attr => {
+                                                       if (attr.isKey)
+                                                       {
+                                                               this.tables[e.name].push({
+                                                                       isKey: e.card.length >= 2 && e.card[1] == 'R', //"weak tables" foreign keys become part of the key
+                                                                       name: "#" + e2.name + "_" + attr.name,
+                                                                       type: attr.type,
+                                                                       qualifiers: "foreign key references " + e2.name + " " + (e.card[0]=='1' : "not null" : ""),
+                                                                       ref: e2.name, //easier drawMld function (fewer regexps)
+                                                               });
+                                                       }
+                                               });
+                                       });
+                               }
+                               else
+                               {
+                                       // Add all keys in current entity
+                                       let fields = e.attributes.filter( attr => { return attr.isKey; });
+                                       newTableAttrs.push({
+                                               fields: fields,
+                                               entity: e.name,
+                                       });
+                               }
+                       }
+                       if (newTableAttrs.length > 1)
+                       {
+                               // Ok, really create a new table
+                               let newTable = {
+                                       name: a.name || newTableAttrs.map( item => { return item.entity; }).join("_");
+                                       fields: [ ],
+                               };
+                               newTableAttrs.forEach( item => {
+                                       item.fields.forEach( f => {
+                                               newTable.fields.push({
+                                                       name: item.entity + "_" + f.name,
+                                                       isKey: true,
+                                                       type: f.type,,
+                                                       qualifiers: (f.qualifiers+" " || "") + "foreign key references " + item.entity + " not null",
+                                                       ref: item.entity,
+                                               });
+                                       });
+                               });
+                               // Add relationship potential own attributes
+                               a.attributes.forEach( attr => {
+                                       newTable.fields.push({
+                                               name: attr.name,
+                                               isKey: false,
+                                               type: attr.type,
+                                               qualifiers: attr.qualifiers,
+                                       });
+                               });
+                               this.tables[newTable.name] = newTable.fields;
+                       }
+               });
+       }
+
+       /////////////////////////////////
+       // DRAWING + GET SQL FROM PARSING
+       /////////////////////////////////
 
        static AjaxGet(dotInput, callback)
        {
@@ -260,9 +336,7 @@ class ErDiags
                        mcdDot += 'node [shape=rectangle, style=rounded];\n';
                let assoceCounter = 0;
                _.shuffle(this.associations).forEach( a => {
-                       let name = !!a.name && a.name.length > 0
-                               ? a.name
-                               : '_assoce' + assoceCounter++;
+                       let name = a.name || "_assoce" + assoceCounter++;
                        if (mcdStyle == "bubble")
                        {
                                mcdDot += '"' + name + '" [shape="diamond", style="filled", color="lightgrey", label="' + name + '"';
@@ -313,7 +387,7 @@ class ErDiags
                });
        }
 
-       // "Modèle logique des données"
+       // "Modèle logique des données", from MCD without anomalies
        // TODO: this one should draw links from foreign keys to keys (port=... in <TD>)
        drawMld(id)
        {
@@ -325,26 +399,27 @@ class ErDiags
                }
                // Build dot graph input (assuming foreign keys not already present...)
                let mldDot = 'graph {\n';
-               // Pass 1: initialize tables
-               let tables = [ ];
-               Object.keys(this.entities).forEach( name => {
-                       tables.push({ name: this.entities[name] }); //TODO: should be a (deep) copy
-               });
-               // Pass 2: parse associations, add foreign keys + new tables
-               this.associations.forEach( a => {
-                       a.entities.forEach( e => { // e.card e.name ...
-                               switch (e.card)
+               mldDot += 'node [shape=plaintext];\n';
+               let links = "";
+               _.shuffle(Object.keys(this.tables)).forEach( name => {
+                       mldDot += '"' + name + '" [label=<<table BORDER="1" ALIGN="LEFT" CELLPADDING="5" CELLSPACING="0">\n';
+                       mldDot += '<tr><td BGCOLOR="#ae7d4e" BORDER="0"><font COLOR="#FFFFFF">' + name + '</font></td></tr>\n';
+                       this.tables[name].fields.forEach( f => {
+                               let label = (f.isKey ? '<u>' : '') + (!!f.qualifiers && f.qualifiers.indexOf("foreign")>=0 ? '#' : '') + f.name + (f.isKey ? '</u>' : '');
+                               mldDot += '<tr><td port="' + f.name + '"' + (f.isKey ? ' port="__key"' : '')
+                                       + ' BGCOLOR="#FFFFFF" BORDER="0" ALIGN="LEFT"><font COLOR="#000000" >' + label + '</font></td></tr>\n';
+                               if (!!f.ref)
                                {
-                                       case '?':
-                                       case '?R': //"weak tables" foreign keys become part of the key
-                                               // TODO
-                               // multi-arite : sub-loop si 0,1 ou 1,1 : aspiré comme attribut de l'association (phase 1)
-                               // ensuite, que du 0,n ou 1,n : si == 1, OK une table
-                               // si 2 ou + : n tables + 1 pour l'assoce, avec attrs clés étrangères
-                               // clé étrangère NOT NULL si 1,1
+                                       if (Math.random() < 0.5)
+                                               links += '"' + f.ref + '":__key -- "' + '"'+name+'":"'+f.name+'"\n';
+                                       else
+                                               links += '"'+name+'":"'+f.name+'" -- "' + f.ref + '":__key\n';
+                               }
                        });
+                       mldDot += '</table>>];\n';
                });
-               // this.graphMld = ...
+               mldDot += links + '\n';
+               mldDot += '}\n';
                //console.log(mldDot);
                ErDiags.AjaxGet(mldDot, graphSvg => {
                        this.mldGraph = graphSvg;
@@ -360,6 +435,20 @@ class ErDiags
                        element.innerHTML = this.sqlText;
                        return;
                }
-               //UNIMPLEMENTED (should be straightforward from MLD)
+               let sqlText = "";
+               Object.keys(this.tables).forEach( name => {
+                       sqlText += "CREATE TABLE " + name + " (\n";
+                       let key = "";
+                       this.tables[name].forEach( f => {
+                               sqlText += f.name + " " + (f.type || "TEXT") + (" "+f.qualifiers || "") + ",\n";
+                               if (f.isKey)
+                                       key += (key.length>0 ? "," : "") + f.name;
+                       });
+                       sqlText += "PRIMARY KEY (" + key + ")\n";
+                       sqlText += ");\n";
+               });
+               //console.log(sqlText);
+               this.sqlText = sqlText;
+               element.innerHTML = "<pre><code>" + sqlText + "</code></pre>";
        }
 }