Allow clients to add more attributes to html output

.travis.yml

@@ -2,6 +2,9 @@ language: php
 php:
   - 5.4
   - 5.3
+before_install:
+  - sudo apt-get update -qq
+  - sudo apt-get install -qq graphviz
 before_script:
   - composer install --dev --prefer-source --no-interaction
 script:

lib/Fhaculty/Graph/GraphViz.php

@@ -219,6 +219,30 @@ public function createImageSrc()
         return 'data:image/' . $format . ';base64,' . base64_encode($this->createImageData());
     }
 
+    /**
+     * Create a DomElement for clients to enrich.
+     *
+     * @code
+     * $domElement = $graphviz->createImageObject();
+     * $domElement->setAttribute('width', '100%');
+     * return $domElement->ownerDocument->saveHtml($domElement);
+     * @endcode
+     *
+     * @return \DomElement
+     */
+    public function createImageObject() {
+        $dom = new \DOMDocument('1.0', 'utf-8');
+        if ($this->format === 'svg' || $this->format === 'svgz') {
+            $domElement = $dom->createElement('object');
+            $domElement->setAttribute('type', 'image/svg+xml');
+            $domElement->setAttribute('data', $this->createImageSrc());
+        }
+        else {
+            $domElement = $dom->createElement('img');
+            $domElement->setAttribute('src', $this->createImageSrc());
+        }
+        return $domElement;
+    }
     /**
      * create image html code for this graph
      *
@@ -227,11 +251,8 @@ public function createImageSrc()
      */
     public function createImageHtml()
     {
-        if ($this->format === 'svg' || $this->format === 'svgz') {
-            return '<object type="image/svg+xml" data="' . $this->createImageSrc() . '"></object>';
-        }
-
-        return '<img src="' . $this->createImageSrc() . '" />';
+        $domElement = $this->createImageObject();
+        return $domElement->ownerDocument->saveHtml($domElement);
     }
 
     /**

tests/Fhaculty/Graph/GraphVizTest.php

@@ -197,4 +197,41 @@ private function getDotScriptForGraph(Graph $graph)
         $graphviz = new GraphViz($graph);
         return $graphviz->createScript();
     }
+
+    public function testImageResult()
+    {
+        $graph = new Graph();
+        $graph->createVertex('a')->createEdgeTo($graph->createVertex('b'));
+        $graph->createVertex('c')->createEdge($graph->getVertex('b'));
+
+        $graphviz = new GraphViz($graph);
+        $graphviz->setFormat('png');
+        $result = $graphviz->createImageHtml();
+        $this->assertStringStartsWith('<img src="data:image/png', $result, "Image HTML has img tag");
+
+        $graphviz = new GraphViz($graph);
+        $domElement = $graphviz->createImageObject();
+        $this->assertNotEmpty($domElement->getAttribute('src'), "src element exists");
+        $this->assertEmpty($domElement->getAttribute('AAA'), "AAA element does not exists");
+
+        $domElement->setAttribute('width', '100%');
+        $result = $domElement->ownerDocument->saveHtml($domElement);
+        $this->assertContains('width', $result, "Image HTML has width attribute");
+
+        $graphviz->setFormat('svg');
+        $result = $graphviz->createImageHtml();
+        $this->assertStringStartsWith('<object type="image/svg', $result, "Image HTML has object tag");
+
+        $graphviz->setFormat('svg');
+        $domElement = $graphviz->createImageObject();
+        $this->assertNotEmpty($domElement->getAttribute('type'), "type element exists");
+        $this->assertNotEmpty($domElement->getAttribute('data'), "data element exists");
+        $this->assertEmpty($domElement->getAttribute('AAA'), "AAA element does not exists");
+
+        $domElement->setAttribute('width', '100%');
+        $result = $domElement->ownerDocument->saveHtml($domElement);
+        $this->assertContains('width', $result, "Image HTML has width attribute");
+
+    }
+
 }