Zend Framework

For those of you who want to participate in the ZCEGuide.com Zend Framework Proposal competition, the deadline of October 31st is fast approaching.

So be sure to enter today!

- Davey

I have been working closely with Matthew Weier O'Phinney for the last week on bringing my Zend_Service_Server proposal to fruition.

There have been several changes, but the core has not moved too far. Matthew, Andi and I have decided that we will first implement the different server/client libraries, that is:

• Zend_Rest_Server and Zend_Rest_Client
• Zend_XmlRpc_Server and Zend_XmlRpc_Client (already released)

In addition to this, there will be a major WSDL supplement for the SOAP extension, this includes:

• Zend_Soap_Wsdl - Generic WSDL creation, manual calls to create a custom WSDL
• Zend_Soap_Wsdl_Parser - WSDL Parser
• Zend_Soap_Wsdl_CodeGenerator (name pending) - WSDL -> PHP Code Skeleton
• Zend_Soap_AutoDiscover - Following the same API as the servers above, this will allow you to automatically generate WSDL from a PHP class or functions.

The core to all of these is found under Zend_Server, these are:

• Zend_Server_Reflection - PHP Class and Function Reflection, including docblock parses and the ability to serialize for caching
• Zend_Server_Interface - Make a compatible Server of your own
• Zend_Server_Abstract - Some stuff you'll almost always need in a server

Furthermore, as an exercise today I spent an entire 20 minutes implementing Zend_Json_Server which works in the same way, register any normal class or functions and any responses will be returned as JSON. What this means is it is now super easy to deploy and utilize Server to Server SOAP/XML-RPC/REST services, and also Client to Server JSON or REST services - all with very little work. Code Re-use is definitely utilized to the maximum here.

We are still working out the finalities with Zend_Server_Reflection and also the Zend_Service_Server replacement, that is the unified API that will automatically dispatch to any of these services.

The final part of this will be the automated HTML documentation, based on the reflection. This will be optional to expose (defaults to on), but a great way to simply code and forget. Documentation is probably the single most important part of an external API - if nobody knows how to use it, well, then it's just pointless.

This is very exciting for me, I hope others will see this a major step forward for "Enterprise" solutions.

- Davey

I am currently working on a ton of Web Services related things for the Zend Framework, one of my favorite, is the almost complete, Zend_Rest_Client. This is a replacement for Zend_Rest (as we're adding a server also).

Whilst it is almost impossible to emulate the PHP 5 SOAP extension, it is still possible to get a nice interface.

I could have made it so that if you call a method, other than the get/post/put/delete methods it would query a Zend REST server correctly, however I wanted to do something nice that was applicable to all REST web services. So I have come up with a client that allows the following three calls:

<?php
$client = new Zend_Rest_Client('http://.../service.php');
echo $client->sayHello('Davey', 'Day')->get();
?>

This first one connects to a Zend_Rest_Server, and it therefore knows the format of the response and returns a string (in this case, it can also return arrays) directly from the get() call. The entire function will send the request:

http://..../service.php?method=sayHello&arg1=Davey&arg2=Day which the Zend_Rest_Server will translate to the TestClass::sayHello($who, $when); call (though it's not a static call). TestClass is the class registered with the server - just like ext/soap.

Furthermore, there is a "fluent" API, for regular REST services:

<?php
$client = new Zend_Rest_Client('http://api.flickr.com/services/rest/');
echo $client->method('flickr.test.echo')->name('Davey Shafik')->api_key($flickr_key)->get()->name;
?>

This time, we need to access the name property on the return value for get(), this is because we don't know the format of the response (it's a call to the Flickr REST service), but you do. If there is only one node called name in the XML, we return it as a string (it's overloaded), otherwise, you will get a SimpleXMLElement array (more on this after the next example); or null for nothing found.

This time, it calls http://api.flickr.com/services/rest/?method=flickr.test.echo&name=Davey%20Shafik&api_key={api key}.

The final look for a call, is just calling things normally, no fluentness:

<?php
$technorati = new Zend_Rest_Client('http://api.technorati.com/bloginfo');
$technorati->key($key);
$technorati->url('http://pixelated-dreams.com');
$result = $technorati->get();
echo $result->firstname .' '. $result->lastname;
?>

Here it calls http://api.technorati.com/bloginfo?key={key}&url=http%3A%2F%2Fpixelated-dreams.com.

In this example, we call directly on $result->firstname and $result->lastname - these don't exist in the root node of the XML returned, but to make things easier, if it is not found, an XPath for (in these cases) firstname and lastname is called respectively. Again a string (shown here) or a SimpleXMLElement array is returned for multiple elements. These calls actually get the
document->result->weblog->author->firstname and document->result->weblog->author->lastname elements.

Whilst this could cause some problems (where same-named nodes are in different portions of the resulting XML and you want a specific one), you can still always access the elements as if the result was a SimpleXMLElement root node directly - this is simply a convenience that obviously pays off in this example.

The only outstanding item I have left is to recursively turn Zend_Rest_Server array responses into real arrays, this will stop you needed to (string) the nodes to use them. I think I will accomplish this using a wrapper object that implements ArrayAccess - this ensures the same result API those services that do use Zend_Rest_Server and those that don't, whilst allowing OO access to the resulting values.

- Davey

P.S.
Eat My Shorts RoR

As you most likely know, I have been working with Zend on the Zend Framework for a couple of months now.

The bulk on my tasks there have been working on the Zend_Service* set of classes. This includes the Amazon, Flickr and Yahoo! APIs.

So, as I'm getting more and more into flickr (see http://flickr.com/dshafik for my photo stream) I have been exploring and I saw a very neat set of images which were composites of 50 random flickr images for a given tag.

Well, I liked this enough, I decided that I could do it on-the-fly using PHP, ImageMagick and of course... the Zend Framework.

So, if you could turn your attention to the Flickr Compositor demo and have some fun.

An example image for "Hello" looks like this:

Or, perhaps a little more fun, "Nude" (thanks to Chris Shiflett for pointing this tag out, I've had lots of pretty results):

Finally, what everybody wants to see: The Flickr Compositor Source

- Davey