Application contract

app-contract.md

Application contract

An application must keep to the following rules if it is to stay sane.

ActionController (POST Controller::action_*())

• Must call one and only one UseCase
• Must redirect to ViewController

ViewController (GET Controller::action_*())

• Must call one and only one Data
• Must set response via Controller::$response::body()

SubViewController (View::__construct())

• Must only accept an array('view' => ViewModel) as it's second parameter

ViewModel (ViewModel::__construct())

• Must only accept an array of scalar values, iterables and View objects

Data (Data::retrieve())

• Must accept an array of data and dependencies
• Must return an array (or iterable) of scalar values or iterables

UseCase (UseCase::execute())

• Must accept an array of data and dependencies
• Must throw exception on validation failure which has method ::errors() to retrieve an array of array('field', 'error')
• Can return scalar value indicating an ID of a created object (for redirection purposes)

example-controller.php

<?php

class EventController {

	public function action_create()
	{
		$data = $this->session()->get('event-create', array());
		$this->response->body(new View('event-create', array(
			'view' => new EventCreateViewModel($data),
		)));
	}

	public function action_create_post()
	{
		try
		{
			$id = EventCreateUseCase::execute(array(
				'mapper'  => $this->container()->mapper('Events'),
				'event'   => $this->request->post(),
				'user_id' => $this->session()->get('user_id'),
			));
		}
		catch (ValidationException $e)
		{
			$this->session()->store('event-create', array(
				'event'  => $this->request->post(),
				'errors' => $e->errors(),
			));

			$this->redirect(Route::url('event-create'));
		}

		$this->redirect(Route::url('event-view', compact('id')));
	}

	public function action_edit()
	{
		$data = EventData::retrieve(array(
			'mapper'  => $this->container()->mapper('Events'),
			'id'      => $this->request->param('id'),
			'user_id' => $this->session()->get('user_id'),
		));

		$data['editions'] = $this->session()->get('event-edit', array());

		$this->response->body(new View('event-edit', array(
			'view' => new EventEditViewModel($data),
		)));
	}

	public function action_edit_post()
	{
		$id = $this->request->param('id');

		try
		{
			EventEditUseCase::execute(array(
				'mapper'  => $this->container()->mapper('Events'),
				'event'   => $this->request->post(),
				'user_id' => $this->session()->get('user_id'),
			));
		}
		catch (ValidationException $e)
		{
			$this->session()->store('event-edit', array(
				'event'  => $this->request->post(),
				'errors' => $e->errors(),
			));

			$this->redirect(Route::url('event-edit', compact('id')));
		}

		$this->redirect(Route::url('event-view', compact('id')));
	}

	protected function action_view($tab_callback)
	{
		try
		{
			$data = EventData::retrieve(array(
				'mapper' => $this->container()->mapper('Events'),
				'id'     => $this->request->param('id'),
			));
		}
		catch (NotFoundException $e)
		{
			throw new HTTPException404;
		}

		$data['actionbar'] = new View('event-action-bar', array(
			'view' => new EventActionBarViewModel($data),
		));

		$data['tab'] = $tab_callback($data);

		$this->response->body(new View('event', array(
			'view' => new EventViewModel($data),
		)));
	}

	public function action_timeslots()
	{
		$this->action_view(function ($data)
		{
			return new View('event-timeslots', array(
				'view' => new EventTimeslotsViewModel($data),
			));
		});
	}

	public function action_media()
	{
		$this->action_view(function ($data)
		{
			return new View('event-media', array(
				'view' => new EventMediaViewModel($data),
			));
		});
	}

	protected function action_requests($tab_callback)
	{
		$this->action_view(function ($data) use ($tab_callback)
		{
			$data['request_tab'] = $tab_callback($data);

			return new View('event-requests', array(
				'view' => new EventRequestsViewModel($data),
			));
		});
	}

	public function action_outgoing_requests()
	{
		$this->action_requests(function ($data)
		{
			return new View('event-outgoing-requests', array(
				'view' => new EventOutgoingRequestsViewModel($data),
			));
		});
	}

	public function action_incoming_requests()
	{
		$this->action_requests(function ($data)
		{
			return new View('event-incoming-requests', array(
				'view' => new EventIncomingRequestsViewModel($data),
			));
		});
	}

}