Did I understand right how to build robust php backends with Zend Framework ?

Question

Most of you should know that 'famous' article about "Writing Robust PHP Backends with Zend Framework" After an insteresting reading, i decided to give it a try, since i couldn't be able to find the gold solution to handle my datas.

Then, i tried to write kind of a skeleton, to have a concrete example.

But some points looks weird for me. But I'll tell more about this later.

I removed some code to be clearer. Here is the code :

    // Kind of stdClass. the User Domain Object
    // Nothing more to say, it's just about to have a User object
    // I guess we could do here some business logic like the username should
    // be only alpha, etc..

    class User
    {
        $_data = array('userId', 'userName');
        public function __construct($data = null)
        {
            $this->populate($data);
        }

        public function populate($data = null)
        {
            if ( is_object ($data) )
            {
                $data = (array) $data;
            }

            if ( ! is_array($data) )
            {
                throw new Exception ('Data must be an array or an object');
            }

            foreach ($data as $property => $value)
            {
                $this->$property = $value;
            }
        }

        public function toArray()
        {
            return $this->_data;
        }
    }

   // The UserTable extends Zend_Db_Adapter_Abstract or Zend_Db_Table
   // Here we do things like fetch, add, update, etc...
   // Validating the data depending on the persistent layers which is the db :
   // respect the data types and formats.

   class UserTable extends Zend_Db_Adapter_Abstract
    {
        public function __construct ($options)
        {
            parent::__construct($options);
        }

        public function validateUser($user)
        {
            if ( null == $user->name || len($user->name) >= 30 || len($user->name) <= 0 )
            {
                throw new Zend_Db_Exception ('Username must be between  0 and 30 chars and must not be null');
            } 

            $user->name = $this->quote($user->name);

            return $user;        
        }

        public function createUser(User $user)
        {
            $user = $this->validateUser($user);

            $user = $user->toArray();

            try
            {
                $this->insert('Users', $user);
                $user->id $this->lastInsertId('Users');

            } catch (Zend_Db_Expection $e) {
                echo 'Error while creating user :', $e->getMessage();
            }

            return $user;
        }

        public function updateUser(User $user)
        {
            $user = $this->validateUser($user);

            $user = $user->toArray();

            if (null == $user->id)
            {
                throw new Exception ('User must have an userId to be updated');
            }

            try
            {
                $this->update('Users', $user, 'userId = ' . $user->id);

            } catch (Zend_Db_Expection $e) {
                echo 'Error while updating user :', $e->getMessage();
            }

            return $user;
        }
    }

    // the UserService will be used like an API from the Controller
    // Let says that our adapters must implements an interface for our Service
    // be able to work.
    // It overrides the method provided by the adapter without knowledge of
    // the data is stored. You can then provide another adapter 
    // than DB (like webservice, xml, etc...)
    // But then, if the adapter implements an interface, why should I use 
    // a Service Layer ? Maybe i didn't understand the Service Layer Concept.

    class UserService
    {
        $_adapter = null;

        public function __construct($adapter = null)
        {
            $this->setAdapter($adapter);
        }

        public function setAdapter($adapter = null)
        {
            $this->_adapter = $adaper;
        }

        public function getUserById($id = 0)
        {
            $this->getAdapter()->getUserById($id);
        }

        public function save(User $user)
        {
            if (null != $user->id)
            {
                $this->getAdapter()->createUser($user);
            } else {
                $this->getAdapter()->updateUser($user);
            }
        }

        // proxy method to the PostService
        // let's say that we have getPostsByUser($userId) method within the 
        // PostService class
        // Btw, Maybe we should find a better way to initialize the adapter,
        // to let it less dependent.

        public function getPosts(User $user)
        {
            $postService = new PostService(new PostTable());
            return $postService->getPostsByUser($user->id);
        }
    }



    // The use in a controller is pretty easy, and the controller, just do 
    // what it should in an MVC architecture.
    // get the data from the model, pass it to the view.

    class UserController
    {
        protected $user = null;

        public function init()
        {
            // get the user object from the session
        }
        public function postsAction()
        {
            $userService = new UserService(new UserTable());

            $this->view->posts = $userService->getPostsByUser($user->id);

        }
    }

So the final question is, Did I understand the concept ? or Did i make some mistakes implementing it ?

P.S. : the tags autocompletion didn't work anymore so i wasn't able to provide the right tags.

Answer 1

I think you should take a look at the Zend_Db_Table. It would spare you create the UserTable class.

Also your controller doesn't extend Zend_Controller_Action how comes.

Last things you would probably want to use Zend_From or Zend_Validate to validate your model.

I thing your implementation is not so bad but this article seems to be old to me.