Analysis of the architecture of applications in the Laravel framework

laravel framework is called a "full stack" framework because it handles everything from network services to database management to HTML generation. A vertically integrated web development environment can provide developers with Better experience.

A typical programmer interacts with Laravel through command line tools to generate and manage Laravel project environments. Laravel comes with an excellent command line tool called Artisan that you can use to generate framework code and database schema. Artisan can handle everything from database schema migration to resource and configuration management.

Convention over configuration

One of the interesting features of Laravel is that it imposes some pretty serious rules on how to build web applications. limit. Surprisingly, these restrictions make creating applications much easier—a lot easier. Let's take a look at why.

Laravel differs from other vertically integrated development environments in its strong preference for convention over configuration. While some Java, Python or PHP frameworks often require a lot of XML configuration, Laravel requires almost no configuration to start with (maybe just a few lines in PHP). This avoidance of configuration files makes it very unique, and the recognizable code structure is the same in all Laravel applications.

One project structure to rule them all!

It's no surprise that all Laravel projects basically have the same directory structure - every file in it has its designated place. Through this agreed directory result, developers can be ensured to work according to the "Laravel way".

Figure 1.1 shows what the Laravel project directory structure looks like:

Figure 1.1 Laravel project directory structure

As you can see In this way, Laravel only contains 4 folders, and there are some subfolders under these 4 folders. Is it stressful to see such rich subfolders for the first time? I will introduce them one by one. Most of our development work will be carried out under the app/ folder.

The following is a basic introduction to each folder and file:

is used to store all third-party code in a typical Laravel application, this includes the Laravel source code and its related plugins, and contains additional pre-packaged functionality.

As mentioned above, /app is where all the fun happens, let’s take a deeper look at the structure of this directory.

Figure 1.2 Displays the detailed information of the /app folder:

Figure 1.2 The detailed information of the app folder

The following is a detailed introduction:

##Top-level folder	Function
app	Contains the site's controllers (controllers), models (models), views (views) and assets (resources). These are the main pieces of code that run your website, and you'll spend most of your time on them.
bootstrap	is used to store files needed when the system starts. These files will Called by files such as index.php.
public	This folder is the only one that can be seen by the outside world and is required Point to the directory of your web server. It contains the core boot file index.php of the laravel framework. This directory can also be used to store any public static resources, such as css, Javascript, images, etc.
##vendor

Control how in the application To authenticate, i.e. the authentication driver. ##/app/config/cache.php##/app/config/compile.php##/app/config/database.phpMiscellaneous configuration of the template system. Contains the basic logic and data model Controller class that interacts with and loads the application's view files. Contains some PHP classes that allow Laravel Updates the schema of the current database while keeping all versions of the database in sync. Migration files are generated using Artisan tools. Contains permissions for Artisan tools to use relational data PHP file to populate the database table. ##/app/lang/PHP file that contains the Array of localized strings. By default the directory contains language lines for paging and form validation for the English language. /app/models/ Models are information (data) that represent an application ) and some classes of rules for manipulating data. In most cases, each table in the database will correspond to a model in the application. The majority of the application business logic will be concentrated in the model. /app/start/ Contains links to Artisan tools and global and local contexts Related custom settings. This directory stores the temporary files of Laravel's various services. Files, such as session, cache, compiled view templates. This directory must be writable on the web server. This directory is maintained by Laravel and we don't care.

File folder	Function
/app/config/	Configure the application’s runtime rules, database, session, etc. wait. Contains a number of configuration files for changing various aspects of the framework. Most options returned in configuration files are associated with PHP arrays.
##/app/config/app.php	Various application-level settings , time zone, locale (locale), debug mode and unique encryption keys.
##/app/config/auth.php
If the application utilizes caching To speed up response time, configure this feature here.
You can specify some here Extra class to include compiled files claimed by the 'artisan optimize' command. These should be classes that are included on basically every request to the application.
Contains database-related configuration information , that is, the default database engine and connection information.	##/app/config/mail.php
is the email sending engine The configuration file of the SMTP server, From: header	##/app/config/session.php
Control how Laravel manages user sessions, that is, session driver, session lifetime.	##/app/config/view.php
	/app/controllers
	/app/database/migrations/
	/app/database/seeds/
##/app/storage/
##/app/tests/	This folder provides you with a convenience The location is used for unit testing. If you use PHPUnit, you can use the Artisan tool to execute all your tests at once.
/app/views/	This folder contains controllers or routes The HTML template used. Please note that you can only place template files in this folder. Other static resource files such as css, javascript and images files should be placed in the /public folder.
/app/routes.php	This is your application's routing file, which contains the routing rules that tell Laravel how to connect incoming requests to the closure functions, controllers, and actions handled by the route. The file also contains several event declarations, including those for error pages, that can be used to define view composers.
/app/filters.php	This file contains various applications and Route filtering methods used to alter the results of your application. Laravel has some predefined filters for access control and XSS protection.

Put a lot of thought into creating and naming folders, and the result is an application with a good file system.

What you get here: MVC

Model-View-Controller (MVC)

Let’s get into the high-level aspects of working with a Laravel application Overview. You may have noticed that the standard Laravel application structure consists of an application directory app/, which contains three subdirectories: models/, views/, and controllers/. This reveals that Laravel follows the model-view-controller (MVC) architectural pattern, which forces the separation of "business logic" input to display logical relationships from the graphical user interface (GUI). In the case of Laravel web applications, business logic usually consists of data models like users, blog posts, etc. The GUI is just a web page in the browser. The MVC design pattern is very popular in the field of web development.

Three components of the MVC pattern:

• Model

• View

• Controller

[Note] The original author introduced the three components of MVC in detail here, but I will not introduce them here due to space.

Laravel Components

A typical Laravel application contains the MVC components mentioned above, as shown below:

When interacting with Laravel, the browser sends a request, the web server receives the request and passes it to the Laravel routing engine. Laravel routing receives the request and then redirects to the appropriate controller class method based on the route's URL pattern.

Then the controller class takes over. In some cases, the controller will immediately render a view, which is a template that is converted into HTML and sent back to the browser. More commonly with dynamic websites, the controller interacts with the model, which is a PHP object that represents an element in the application (such as a user, a blog post) and is responsible for communicating with the database. After calling the model, the controller renders the final view (HTML, CSS, and images) and returns the complete web page to the user's browser.

Laravel promotes the concept that models, views, and controllers should be kept fairly independent by storing these elements in separate code files in different directories. This is where the Laravel directory structure comes into play.

Design patterns like MVC were created to make developers’ lives easier. This is where Laravel is better than PHP which does not use any pattern. If this discussion is abstract, now, don't worry! When you start working with Laravel, you won't even realize that you are working in a design pattern. After a while, it will become natural.

Data Model

The data model is the foundation of any application. It describes the business logic of the application. Any piece of data is represented by a database table. Laravel provides some techniques to simplify access to the database.

Laravel connects the application's data model to the database table by converting table rows in the database into PHP objects that can be easily manipulated. It also enables you to enforce business rules, describe relationships between different data models in your application, etc. For example, a person's family relationship can be described using Laravel Eloquent OR/M as follows:

class Person extends Eloquent
{
    public function mother()
    {
        return $this->belongsTo('Mother');
    }

    public function father()
    {
        return $this->belongsTo('Father');
    }

    public function spouse()
    {
        return $this->hasOne('Spouse');
    }

    public function sisters()
    {
        return $this->hasMany('Sister');
    }

    public function brothers()
    {
        return $this->hasMany('Brother');
    }
}

The above is the entire content of this article, more laravel content Please pay attention to the laravel framework introductory tutorial.

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