[Laravel5.2 documentation] architecture-facade (Facades)

[Laravel5.2 documentation] architecture-facade (Facades) 1. Introduction

The facade provides a "static" interface for the binding class in the service container of the application. Laravel has many built-in facades that you may be using without knowing. The facade of Laravel serves as the "static proxy" of the underlying class in the service container. compared with the traditional static method, it provides easier testing, more flexible, concise, and expressive syntax during maintenance.

2. use the facade

In the context of the Laravel application, the facade is a class that provides access to objects in the container. This mechanism is implemented by the Facade class. the Facade provided by Laravel and the created custom Facade will inherit from the Illuminate \ Support \ Facades \ Facade base class.

You only need to implement one method for the facade class: getFacadeAccessor. The getFacadeAccessor method defines what to parse from the container, and then the Facade base class uses the magic method _ callStatic () to call the parsing object from your Facade.

In the following example, we will call Laravel's Cache system. after browsing the code, you may think that we have called the static Cache method get:

 $ User]) ;}}

Note that we have introduced the Cache facade at the top. This facade acts as a proxy to access the implementation of the underlying Illuminate \ Contracts \ Cache \ Factory interface. All calls to the door will be passed to the underlying instance of Laravel cache service.

If we look at the source code of the Illuminate \ Support \ Facades \ Cache class, we will find that there is no static method get:

Class Cache extends Facade {/*** get component registration name ** @ return string */protected static function getFacadeAccessor () {return 'cache ';}}

The Cache Facade inherits the Facade base class and defines the getFacadeAccessor method. the job of this method is to return the alias of the service container binding class. when you reference any static method of the Cache class, laravel parses the cache binding from the service container, and then calls all request methods (in this example, get) on the parsed object ).

3. Portal category list

The following lists each facade and its corresponding underlying classes, which is a useful tool for in-depth API documentation on the given root facade. The service container binding key is also included:

Facade	Class	Bind an alias to a service container
App	Illuminate \ Foundation \ Application	App
Artisan	Illuminate \ Console \ Application	Artisan
Auth	Illuminate \ Auth \ AuthManager	Auth
Auth (Instance)	Illuminate \ Auth \ Guard
Blade	Illuminate \ View \ Compilers \ BladeCompiler	Blade. compiler
Bus	Illuminate \ Contracts \ Bus \ Dispatcher
Cache	Illuminate \ Cache \ Repository	Cache
Config	Illuminate \ Config \ Repository	Config
Cookie	Illuminate \ Cookie \ CookieJar	Cookie
Crypt	Illuminate \ Encryption \ Encrypter	Encrypter
DB	Illuminate \ Database \ DatabaseManager	Db
DB (Instance)	Illuminate \ Database \ Connection
Event	Illuminate \ Events \ Dispatcher	Events
File	Illuminate \ Filesystem	Files
Hash	Illuminate \ Contracts \ Hashing \ Hasher	Hash
Input	Illuminate \ Http \ Request	Request
Lang	Illuminate \ Translation \ Translator	Translator
Log	Illuminate \ Log \ Writer	Log
Mail	Illuminate \ Mail \ Mailer	Mailer
Password	Illuminate \ Auth \ Passwords \ PasswordBroker	Auth. password
Queue	Illuminate \ Queue \ QueueManager	Queue
Queue (Instance)	Illuminate \ Queue \ QueueInterface
Queue (Base Class)	Illuminate \ Queue
Redirect	Illuminate \ Routing \ Redirector	Redirect
Redis	Illuminate \ Redis \ Database	Redis
Request	Illuminate \ Http \ Request	Request
Response	Illuminate \ Contracts \ Routing \ ResponseFactory
Route	Illuminate \ Routing \ Router	Router
Schema	Illuminate \ Database \ Schema \ Blueprint
Session	Illuminate \ Session \ SessionManager	Session
Session (Instance)	Illuminate \ Session \ Store
Storage	Illuminate \ Contracts \ Filesystem \ Factory	Filesystem
URL	Illuminate \ Routing \ UrlGenerator	Url
Validator	Illuminate \ Validation \ Factory	Validator
Validator (Instance)	Illuminate \ Validation \ Validator
View	Illuminate \ View \ Factory	View
View (Instance)	Illuminate \ View