This document is for CakePHP's development version, which can be significantly different from previous releases.
You may want to read current stable release documentation instead.

CakePHP Conventions

We are big fans of convention over configuration. While it takes a bit of time to learn CakePHP’s conventions, you save time in the long run. By following conventions, you get free functionality, and you liberate yourself from the maintenance nightmare of tracking config files. Conventions also make for a very uniform development experience, allowing other developers to jump in and help.

Controller Conventions

Controller class names are plural, CamelCased, and end in Controller. UsersController and MenuLinksController are both examples of conventional controller names.

Public methods on Controllers are often exposed as ‘actions’ accessible through a web browser. They are camelBacked. For example the /users/view-me maps to the viewMe() method of the UsersController out of the box (if one uses default dashed inflection in routing). Protected or private methods cannot be accessed with routing.

URL Considerations for Controller Names

As you’ve just seen, single word controllers map to a simple lower case URL path. For example, UsersController (which would be defined in the file name UsersController.php) is accessed from http://example.com/users.

While you can route multiple word controllers in any way you like, the convention is that your URLs are lowercase and dashed using the DashedRoute class, therefore /menu-links/view-all is the correct form to access the MenuLinksController::viewAll() action.

When you create links using this->Html->link(), you can use the following conventions for the url array:

$this->Html->link('link-title', [
    'prefix' => 'MyPrefix' // CamelCased
    'plugin' => 'MyPlugin', // CamelCased
    'controller' => 'ControllerName', // CamelCased
    'action' => 'actionName' // camelBacked
]

For more information on CakePHP URLs and parameter handling, see Connecting Routes.

File and Class Name Conventions

In general, filenames match the class names, and follow the PSR-4 standard for autoloading. The following are some examples of class names and their filenames:

  • The Controller class LatestArticlesController would be found in a file named LatestArticlesController.php

  • The Component class MyHandyComponent would be found in a file named MyHandyComponent.php

  • The Table class OptionValuesTable would be found in a file named OptionValuesTable.php.

  • The Entity class OptionValue would be found in a file named OptionValue.php.

  • The Behavior class EspeciallyFunkableBehavior would be found in a file named EspeciallyFunkableBehavior.php

  • The View class SuperSimpleView would be found in a file named SuperSimpleView.php

  • The Helper class BestEverHelper would be found in a file named BestEverHelper.php

Each file would be located in the appropriate folder/namespace in your app folder.

Database Conventions

Table names corresponding to CakePHP models are plural and underscored. For example users, menu_links, and user_favorite_pages respectively. Table name whose name contains multiple words should only pluralize the last word, for example, menu_links.

Column names with two or more words are underscored, for example, first_name.

Foreign keys in hasMany, belongsTo/hasOne relationships are recognized by default as the (singular) name of the related table followed by _id. So if Users hasMany Articles, the articles table will refer to the users table via a user_id foreign key. For a table like menu_links whose name contains multiple words, the foreign key would be menu_link_id.

Join (or “junction”) tables are used in BelongsToMany relationships between models. These should be named for the tables they connect. The names should be pluralized and sorted alphabetically: articles_tags, not tags_articles or article_tags. The bake command will not work if this convention is not followed. If the junction table holds any data other than the linking foreign keys, you should create a concrete entity/table class for the table.

In addition to using an auto-incrementing integer as primary keys, you can also use UUID columns. CakePHP will create UUID values automatically using (Cake\Utility\Text::uuid()) whenever you save new records using the Table::save() method.

Model Conventions

Table class names are plural, CamelCased and end in Table. UsersTable, MenuLinksTable, and UserFavoritePagesTable are all examples of table class names matching the users, menu_links and user_favorite_pages tables respectively.

Entity class names are singular CamelCased and have no suffix. User, MenuLink, and UserFavoritePage are all examples of entity names matching the users, menu_links and user_favorite_pages tables respectively.

View Conventions

View template files are named after the controller functions they display, in an underscored form. The viewAll() function of the ArticlesController class will look for a view template in templates/Articles/view_all.php.

The basic pattern is templates/Controller/underscored_function_name.php.

Note

By default CakePHP uses English inflections. If you have database tables/columns that use another language, you will need to add inflection rules (from singular to plural and vice-versa). You can use Cake\Utility\Inflector to define your custom inflection rules. See the documentation about Inflector for more information.

Plugins Conventions

It is useful to prefix a CakePHP plugin with “cakephp-” in the package name. This makes the name semantically related on the framework it depends on.

Do not use the CakePHP namespace (cakephp) as vendor name as this is reserved to CakePHP owned plugins. The convention is to use lowercase letters and dashes as separator:

// Bad
cakephp/foo-bar

// Good
your-name/cakephp-foo-bar

See awesome list recommendations for details.

Summarized

By naming the pieces of your application using CakePHP conventions, you gain functionality without the hassle and maintenance tethers of configuration. Here’s a final example that ties the conventions together:

  • Database table: “articles”, “menu_links”

  • Table class: ArticlesTable, found at src/Model/Table/ArticlesTable.php

  • Entity class: Article, found at src/Model/Entity/Article.php

  • Controller class: ArticlesController, found at src/Controller/ArticlesController.php

  • View template, found at templates/Articles/index.php

Using these conventions, CakePHP knows that a request to http://example.com/articles maps to a call on the index() method of the ArticlesController, where the Articles model is automatically available. None of these relationships have been configured by any means other than by creating classes and files that you’d need to create anyway.

Example

articles

menu_links

Database Table

articles

menu_links

Table names corresponding to CakePHP models are plural and underscored.

File

ArticlesController.php

MenuLinksController.php

Table

ArticlesTable.php

MenuLinksTable.php

Table class names are plural, CamelCased and end in Table

Entity

Article.php

MenuLink.php

Entity class names are singular, CamelCased: Article and MenuLink

Class

ArticlesController

MenuLinksController

Controller

ArticlesController

MenuLinksController

Plural, CamelCased, end in Controller

Behavior

ArticlesBehavior.php

MenuLinksBehavior.php

View

ArticlesView.php

MenuLinksView.php

View template files are named after the controller functions they display, in an underscored form

Helper

ArticlesHelper.php

MenuLinksHelper.php

Component

ArticlesComponent.php

MenuLinksComponent.php

Plugin

Bad: cakephp/articles Good: you/cakephp-articles

cakephp/menu-links you/cakephp-menu-links

Useful to prefix a CakePHP plugin with “cakephp-” in the package name. Do not use the CakePHP namespace (cakephp) as vendor name as this is reserved to CakePHP owned plugins. The convention is to use lowercase letters and dashes as separator.

Each file would be located in the appropriate folder/namespace in your app folder.

Database Convention Summary

Foreign keys

hasMany belongsTo/ hasOne BelongsToMany

Relationships are recognized by default as the (singular) name of the related table followed by _id. Users hasMany Articles, articles table will refer to the users table via a user_id foreign key.

Multiple Words

menu_links whose name contains multiple words, the foreign key would be menu_link_id.

Auto Increment

In addition to using an auto-incrementing integer as primary keys, you can also use UUID columns. CakePHP will create UUID values automatically using (Cake\Utility\Text::uuid()) whenever you save new records using the Table::save() method.

Join tables

Should be named after the model tables they will join or the bake command won’t work, arranged in alphabetical order (articles_tags rather than tags_articles). Additional columns on the junction table you should create a separate entity/table class for that table.

Now that you’ve been introduced to CakePHP’s fundamentals, you might try a run through the Content Management Tutorial to see how things fit together.