Added some checks to the displayMetadata method so that it does not cause errors if the exif datastream is empty or missing.

plugins/Exiftool.inc

@@ -32,32 +32,35 @@ class Exiftool {
   
   function displayMetadata() { 
     $output='';
-    $exifDom = DOMDocument::loadXML($this->item->get_datastream_dissemination('EXIF'));
-    if ($exifDom != NULL) {
-      $description = $exifDom->getElementsByTagNameNS('http://www.w3.org/1999/02/22-rdf-syntax-ns#','Description');
-      if ($description->length > 0) { 
-	$description=$description->item(0);
-	$output .= '<div class="fedora_technical_metadata"><ul>';
-	for ($i=0;$i<$description->childNodes->length;$i++){ 
-	  $name=$description->childNodes->item($i)->nodeName;
-	  $value=$description->childNodes->item($i)->nodeValue;
-	  if ($name != '#text'  && !preg_match('/^System\:.*$/',$name) && trim($value) != '') { 
-	    list($type,$name) = preg_split('/\:/',$name);
-	    $name = trim(preg_replace('/(?<!^)([A-Z][a-z]|(?<=[a-z])[A-Z])/'," $1", $name));
-	    $output .= '<li><b>'.$name. '</b>:  '. $value .' </li>';
-	  }
-	}
-	$output.='</ul></div>';
+		$exif = $this->item->get_datastream_dissemination('EXIF'); 
+		if (trim($exif) != '')  {
+	    $exifDom = DOMDocument::loadXML($this->item->get_datastream_dissemination('EXIF'));
+  	  if ($exifDom != NULL) {
+	      $description = $exifDom->getElementsByTagNameNS('http://www.w3.org/1999/02/22-rdf-syntax-ns#','Description');
+  	    if ($description->length > 0) { 
+					$description=$description->item(0);
+					$output .= '<div class="fedora_technical_metadata"><ul>';
+					for ($i=0;$i<$description->childNodes->length;$i++){ 
+					  $name=$description->childNodes->item($i)->nodeName;
+				  	$value=$description->childNodes->item($i)->nodeValue;
+		  			if ($name != '#text'  && !preg_match('/^System\:.*$/',$name) && trim($value) != '') { 
+					    list($type,$name) = preg_split('/\:/',$name);
+				  	  $name = trim(preg_replace('/(?<!^)([A-Z][a-z]|(?<=[a-z])[A-Z])/'," $1", $name));
+	    				$output .= '<li><b>'.$name. '</b>:  '. $value .' </li>';
+					  }
+					}
+					$output.='</ul></div>';
 	
-	$fieldset = array(
-	  '#title' => t("!text", array('!text' => 'Technical Metadata')),
-	  '#collapsible' => TRUE,
-	  '#collapsed' => TRUE,
-	  '#value' => $output
-	);
-	$output  = theme('fieldset', $fieldset);
-      }
-    }
+					$fieldset = array(
+					  '#title' => t("!text", array('!text' => 'Technical Metadata')),
+				  	'#collapsible' => TRUE,
+					  '#collapsed' => TRUE,
+					  '#value' => $output
+					);
+					$output  = theme('fieldset', $fieldset);
+	      }
+  	  }
+	  }
     return $output;
   }