Scaffolding
Application scaffolding is a technique that allows a developer to define and create a basic application that
can create, retrieve, update and delete objects. Scaffolding in CakePHP also allows developers to define how
objects are related to each other, and to create and break those links.
All that’s needed to create a scaffold is a model and its controller. Once you set the $scaffold variable in the
controller, you’re up and running.
CakePHP’s scaffolding is pretty cool. It allows you to get a basic CRUD application up and going in minutes.
It’s so cool that you’ll want to use it in production apps. Now, we think it’s cool too, but please realize that
scaffolding is... well... just scaffolding. It’s a loose structure you throw up real quick during the beginning
of a project in order to get started. It isn’t meant to be completely flexible, it’s meant as a temporary way
to get up and going. If you find yourself really wanting to customize your logic and your views, it’s time
to pull your scaffolding down in order to write some code. CakePHP’s Bake console, covered in the next
section, is a great next step: it generates all the code that would produce the same result as the most current
scaffold.
Scaffolding is a great way of getting the early parts of developing a web application started. Early database
schemas are subject to change, which is perfectly normal in the early part of the design process. This has
a downside: a web developer hates creating forms that never will see real use. To reduce the strain on the
developer, scaffolding has been included in CakePHP. Scaffolding analyzes your database tables and creates
standard lists with add, delete and edit buttons, standard forms for editing and standard views for inspecting
a single item in the database.To add scaffolding to your application, in the controller, add the $scaffold variable:
class CategoriesController extends AppController {
public $scaffold;
}
Assuming you’ve created even the most basic Category model class file (in /app/Model/Category.php),
you’re ready to go. Visit http://example.com/categories to see your new scaffold.
Note: Creating methods in controllers that are scaffolded can cause unwanted results. For example, if
you create an index() method in a scaffolded controller, your index method will be rendered rather than the
scaffolding functionality.
Scaffolding is knowledgeable about model associations, so if your Category model belongsTo a User, you’ll
see related User IDs in the Category listings. While scaffolding “knows” about model associations, you will
not see any related records in the scaffold views until you manually add the association code to the model.
For example, if Group hasMany User and User belongsTo Group, you have to manually add the following
code in your User and Group models. Before you add the following code, the view displays an empty select
input for Group in the New User form. After you add the following code, the view displays a select input
populated with IDs or names from the Group table in the New User form:
// In Group.php
public $hasMany = ’User’;
// In User.php
public $belongsTo = ’Group’;
If you’d rather see something besides an ID (like the user’s first name), you can set the $displayField variable
in the model. Let’s set the $displayField variable in our User class so that users related to categories will be
shown by first name rather than just an ID in scaffolding. This feature makes scaffolding more readable in
many instances:
class User extends AppModel {
public $displayField = ’first_name’;
}
Creating a simple admin interface with scaffolding
If you have enabled admin routing in your app/Config/core.php, with
Configure::write(’Routing.prefixes’, array(’admin’)); you can use scaffolding
to generate an admin interface.
Once you have enabled admin routing assign your admin prefix to the scaffolding variable:
public $scaffold = ’admin’;
You will now be able to access admin scaffolded actions:
http://example.com/admin/controller/index
http://example.com/admin/controller/view
http://example.com/admin/controller/edit