[DBAL-107] Add very simple graphviz schema visitor inspired by phUML (thanks jakob!).

lib/Doctrine/DBAL/Schema/Visitor/Graphviz.php

+<?php
+
+/*
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * This software consists of voluntary contributions made by many individuals
+ * and is licensed under the LGPL. For more information, see
+ * <http://www.doctrine-project.org>.
+ */
+
+namespace Doctrine\DBAL\Schema\Visitor;
+
+use Doctrine\DBAL\Platforms\AbstractPlatform,
+ Doctrine\DBAL\Schema\Table,
+ Doctrine\DBAL\Schema\Schema,
+ Doctrine\DBAL\Schema\Column,
+ Doctrine\DBAL\Schema\ForeignKeyConstraint,
+ Doctrine\DBAL\Schema\Constraint,
+ Doctrine\DBAL\Schema\Sequence,
+ Doctrine\DBAL\Schema\Index;
+
+class Graphviz implements \Doctrine\DBAL\Schema\Visitor\Visitor
+{
+    private $output = '';
+
+    public function acceptColumn(Table $table, Column $column)
+    {
+        
+    }
+
+    public function acceptForeignKey(Table $localTable, ForeignKeyConstraint $fkConstraint)
+    {
+        $this->output .= $this->createNodeRelation(
+            $fkConstraint->getLocalTableName(),
+            $fkConstraint->getForeignTableName(),
+            array(
+                'dir'       => 'back',
+                'arrowtail' => 'dot',
+                'arrowhead' => 'normal',
+            )
+        );
+    }
+
+    public function acceptIndex(Table $table, Index $index)
+    {
+        
+    }
+
+    public function acceptSchema(Schema $schema)
+    {
+        $this->output  = 'digraph "' . sha1( mt_rand() ) . '" {' . "\n";
+        $this->output .= 'splines = true;' . "\n";
+        $this->output .= 'overlap = false;' . "\n";
+        $this->output .= 'mindist = 0.6;' . "\n";
+        $this->output .= 'sep = .2;' . "\n";
+    }
+
+    public function acceptSequence(Sequence $sequence)
+    {
+        
+    }
+
+    public function acceptTable(Table $table)
+    {
+        $name = $table->getName();
+        $columns = array();
+        foreach ($table->getColumns() AS $column) {
+            $name = $column->getName();
+            if (in_array($name, $table->getPrimaryKey()->getColumns())) {
+                $name =  $name . " \xe2\x9c\xb6";
+            }
+
+            $columns[] = $name;
+        }
+
+        $this->output .= $this->createNode(
+            $table->getName(),
+            array(
+                'label' => $this->createTableLabel( $name, $columns ),
+                'shape' => 'plaintext',
+            )
+        );
+    }
+
+    private function createTableLabel( $name, $columns )
+    {
+        // Start the table
+        $label = '<<TABLE CELLSPACING="0" BORDER="0" ALIGN="LEFT">';
+
+        // The title
+        $label .= '<TR><TD BORDER="1" ALIGN="CENTER" BGCOLOR="#fcaf3e"><FONT COLOR="#2e3436" FACE="Helvetica" POINT-SIZE="12">' . $name . '</FONT></TD></TR>';
+
+        // The attributes block
+        $label .= '<TR><TD BORDER="1" ALIGN="LEFT" BGCOLOR="#eeeeec">';
+        if ( count( $columns ) === 0 ) {
+            $label .= ' ';
+        }
+        foreach( $columns as $attribute ) {
+            $label .= '<FONT COLOR="#2e3436" FACE="Helvetica" POINT-SIZE="10">' . $attribute . '</FONT><BR ALIGN="LEFT"/>';
+        }
+        $label .= '</TD></TR>';
+
+        // End the table
+        $label .= '</TABLE>>';
+
+        return $label;
+    }
+
+    private function createNode( $name, $options )
+    {
+        $node = $name . " [";
+        foreach( $options as $key => $value )
+        {
+            $node .= $key . '=' . $value . ' ';
+        }
+        $node .= "]\n";
+        return $node;
+    }
+
+    private function createNodeRelation( $node1, $node2, $options )
+    {
+        $relation = $node1 . ' -> ' . $node2 . ' [';
+        foreach( $options as $key => $value )
+        {
+            $relation .= $key . '=' . $value . ' ';
+        }
+        $relation .= "]\n";
+        return $relation;
+    }
+
+    /**
+     * Write dot language output to a file. This should usually be a *.dot file.
+     *
+     * You have to convert the output into a viewable format. For example use "neato" on linux systems
+     * and execute:
+     *
+     *  neato -Tpng -o er.png er.dot 
+     *
+     * @param string $filename
+     * @return void
+     */
+    public function write($filename)
+    {
+        file_put_contents($filename, $this->output . "}");
+    }
+}
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