Article ezComponents 2008.2 Beta - Mvc separation for win

I have written on the new ezComponents MvcTools component before already. Just yesterday the beta of this component was released with the general beta of the 2008.2 version of ezComponents. Several bugfixes and enhancements were included into the MvcTools which make it a perfect component for any Mvc based application.

I reviewed lots of the code myself and can only say i love the beauty of the code. Its very simple but by default the most powerful mvc solution in the PHP market. People working with unittests will like it very much, since all the parts are perfectly separated from each other allowing to test controllers, views, routers and filters in complete separation.

To show one very simple example howto benefit of the separation of view and controllers. If we need a view in both html and pdf, this should generally make no difference for the controller. We add two routes, one for the pdf one for the html view that execute the same controller and action:

class myRouter extends ezcMvcRouter{ public function createRoutes() {  return array(   new ezcMvcRailsRoute( '/pdf', 'SomeController', 'index'),   new ezcMvcRailsRoute( '/', 'SomeController', index' ),  ); }}class SomeController extends ezcMvcController{ public function doIndex() {  $result = new ezcMvcResult();  $result->variables['items'] = Model::retrieveLotsOfItems();  return $result; }}

Now howto decide between PDF and Html view? We use the createView method of our dispatcher configuration, but we still only need the http response writer, nothing more.

class myMvcConfiguration implements ezcMvcDispatcherConfiguration { [...] function createView( ezcMvcRoutingInformation $routeInfo, ezcMvcRequest $request, ezcMvcResult $result ) {  if(strstr($routeInfo->matchedRoute, "/pdf")) {   return new myHtmlView( $request, $result );  } else {   return new myPdfView( $request, $result );  } } function createResponseWriter( ezcMvcRoutingInformation $routeInfo, ezcMvcRequest $request, ezcMvcResult $result, ezcMvcResponse $response ) {  return new ezcMvcHttpResponseWriter( $response ); } [...]}

Now both myHtmlView and myPdfView can create their ezcMvcResponse objects that fill the response body depending on their type. Please note that overwriting createResponseBody() in myPdfView is a shortcut that circumvents me having to write a new PDF View Handler (which would be the way to go).

class myHtmlView extends ezcMvcView { function createZones( $layout ) {  $zones = array();   $zones[] = new ezcMvcPhpViewHandler( 'content', '../templates/index.phtml' );  $zones[] = new ezcMvcPhpViewHandler( 'page_layout', '../templates/layout.phtml' );  return $zones; }}class myPdfView extends ezcMvcView { function createZones() {  // empty, abstract method that has to be defined. } function createResponseBody() {  // Set PDF Content-Type Response Header  $this->result->content->type = "application/pdf";   $pdf = new Zend_Pdf();  // do pdf stuff  return $pdf->render(); }}

Now all the the logic that is potentially in the controller is completely separated from the view handling that may depend on the routing information not on the controller. And views can be tested separately from the controller result. Testability is very high.

Published: 2008-12-03 Tags: #eZComponents