Laravel 5 interview questions

There is quite a requisite for the installation of Laravel 6. And, below is the list of the required servers that are needed for the installment of it.

• PHP 7.2.0 version
• Extension of BCMath PHP
• JSON PHP Extension
• XML PHP Extension
• Extension of Ctype PHP
• Extension of Tokenizer PHP 
• Mbstring PHP Extension
• PDO PHP Extension
• OpenSSL PHP

Composer is a tool to manage the dependency in PHP. Composer allows declaring the libraries of a project and the composer will install or update them for the user. It is not a package manager but deals with the libraries or packages and install them inside the project directory. The composer is downloaded by the installer in the windows and sets up a path for the environment that can be called from any directory.

The composer can be installed using a command

$curl -sS https://getcomposer.org/installer | 
sudo php -- --install-dir=/usr/local/bin --filename=composer

To create a Laravel project using composer you can follow the given steps:

• Step 1: Point your browser address bar to https://getcomposer.org/composer.phar
• Step 2: Create a new Laravel project. While in Terminal, browse where you want to set up your app and run the below command: composer create-project laravel/laravel demowebsite.
• Step 3: Configure virtual host and system host.

Laravel Homestead helps in providing you a development environment and also that too without the installation of the PHP, HHVM, web server or any such thing in your local machine. It is completely disposable. This gives you the power to destroy if anything goes wrong and then you can just reuse it or recreate the same thing in just a few minutes.

We can run the Laravel Development server by typing PHP artisan serve command on terminal or command line in Larvel and always make sure it is present in your Laravel's project root directory else change your present working directory.

Valet can be defined as a tool that mainly helps to spin up a demo or those projects that are considered to be discardable as a breeze. The main function of valet is to combine various default software on the operating system with some creative and innovative ideas that are related to file paths and serving of PHP applications. In addition to that, they combine with some extra tools used for eliminating the requirement of modifying the /etc/hosts file.

The steps to Configure Laravel application are:

• First, download the Laravel installer using Composer: composer global require laravel/installer
• Create a new directory somewhere on your computer for the Laravel project that you are going to create and type the command: composer create-project laravel/laravel –-prefer-dist 
• Install the complete Laravel framework: composer create-project laravel/laravel test dev-develop
•  Enable the installation of Laravel in the current directory: php artisan serve

In order to run Laravel, the directories within the storage and the bootstrap/cache directories should be writable by your web server otherwise the Laravel will not run.

You can use PHP artisan key: generate to generate Application Key in laravel.

You can create SEO-friendly URLs in Laravel by adding the following features:

• Website speed must be fast
• Responsive designs to   have a significant market share of internet usage
• Keywords must be appropriate
• The URLs should be separated by dashes instead of underscores.

All of the directory laravel configuration files are kept in config directory.

Environment Configuration in Laravel can be done by following steps:

• Environment Configuration
• Accessing Configuration Values
• Caching of Configuration
• Maintenance Mode

You can retrieve values for Laravel configuration files by using env helper to retrieve values from these variables in your configuration files.

The entire variable listed in a (.env) the file will be loaded in the $_ENV PHP when a request is received by an application. However, an ENV helper may be implemented to retrieve the values of the variables in a particular configuration file. If a Laravel configuration file is reviewed, several options can be noticed to assists these helpers in the following way:

‘Debug’=> env ('APP_DEBUG', false?),

The second value that is passed onto the env function is the default value. This value can be used if there is no environment variable present in the given key.

To get/set configuration values in Laravel, you can simply use config helper of Laravel or config facade. You can use the following syntaxes for using get and set configuration values.

• Get Config Variable Value: $url = config('app.url');  OR  $url = Config::get('app.url'); 
• Set Config Variable Value:  $url = config('app.url','http://interviewmocks.com/');   OR  $url = Config::set('app.url','http://interviewmocks.com/');

The maintenance mode in a Laravel can be enabled or disabled by artisan CLI.

Laravel returns a custom view that can be displayed in all requests when the website is in a maintenance mode. Thus, it becomes easier to enable or disable an application or a website while it is still under maintenance or updating.

To enable the maintenance mode in Laravel, the following artisan command should be entered into the command line:

php artisan down

To disable the maintenance mode in Laravel, the following artisan command should be executed in the command line:

php artisan up

The storage directory contains files such as, blade templates, sessions, caches, and log files plus app storage like uploads, etc which are required frequently when a Laravel project is running.

Laravel Homestead is a pre-packaged and official Vagrant "box", that offers a great improvement environment without needing one to install HHVM, PHP, web servers or any distinct server software on your local machine.

It functions on every Mac, Linux system, Windows, Nginx web servers, PHP 7.2, PHP 7.1, PHP 7.3, PostgreSQL, Redis, MySQL, Node, Memcached and every other article one requires to improve the outstanding Laravel applications.

There are numerous Softwares included in Laravel Homestead. Some of these are:

• Ubuntu 14.04.
• PHP 5.6.
• HHVM.
• Nginx.
• MySQL.
• Postgres.
• Node (With Bower, Grunt, and Gulp)
• Redis.

To install Homestead Vagrant Box, you have to unfurl git bash and execute the command "vagrant box add laravel/homestead"

The steps to Configure Homestead are as follows:

• Hardware Virtualization
• Downloading VirtualBox and Vagrant
• Install Git Bash
• Installing Homestead Box
• Cloning Homestead
• Creating ssh keys
• Editing Configuration File
• Editing the Host file
• Starting Homestead
• Creating Laravel project
• Running our Application

Vagrant is a software that is utilized to handle the improvement environment. Via the command line, one can take any available OS, configure it, install it, work within it, run it, and additional functions. Utilizing it one can restore the manufacturing environment of one’s website or app.

To launch Vagrant Box, one has to:

• Start and initialize the Vagrant Box.
• Select a box then arrange the Vagrant Box. 
• Incorporate SSH within the box and Customize It.
• Create the box as tiny as possible. 
• Incorporate the box within one's Vagrant install.
• Customize the new Vagrantfile.

The Vagrantfile is a Ruby file utilized to arrange Vagrant on a per-project way. The chief function of the Vagrantfile is to explain the virtual devices needed for projects with the process of configuration and amenities of the devices.

Laravel Homestead happens to be a pre-packaged Vagrant Box that offers one a marvelous development environment san needing one to install, web servers, PHP, or any distinct server software on one's local machine. These Vagrant Boxes are fully disposable.

You can upgrade Homestead with the help of the following steps:

• Destroy your box and remove the old version.
• Update VirtualBox to 5.1.10 with the extensions if needed.
• Update Vagrant to 1.9.1.
• Rename your Homestead directory to Homestead-0ld.
• Run vagrant box add Lravel/homestead.
• Run vagrant up and that should be it.

You can Install MariaDB on Homestead by following the given step:

• Remove MySQL server.
• sudo apt-get remove --purge MySQL-server MySQL-client MySQL-common
• sudo apt-get autoremove
• sudo apt-get autoclean
• After that install MariaDB
• sudo apt-get install software-properties-common
• sudo apt-key adv --recv-keys --keyserver hkp://keyserver.ubuntu.com:80 0xcbcb082a1bb943db
• sudo add-apt-repository 'deb [arch=amd64,i386] http://sfo1.mirrors.digitalocean.com/mariadb/repo/10.1/ubuntu trusty main'
• sudo apt-get update
• sudo apt-get install mariadb-server
• Now, In your homestead.yaml file, use
• MariaDB: - homestead

You can add ssh config for your vagrant host to ssh config by the following method:

• Get ssh config for the vagrant machine in the vagrant folder: vagrant ssh-config.
• Open {UserDir}/.ssh/config and append their result from the previous command. 
• Ssh to vagrant: ssh vagrant.

You can add an additional site by simply add the site to your ~/. homestead/Homestead. YAML file and then run the vagrant reload --provision terminal command from your Homestead directory.

Homestead assists numerous kinds of sites that permits one to easily execute projects that are not founded on Laravel. The sites supported by Homestead include:

• Symfony4.
• Apache.
• Laravel. 
• Proxy. 
• Symfony2.
• Statamic. 
• SilverStripe.

There are numerous ways to configure Cron in Homestead like:

• Make new Artisan command and register it within the Kernel. Then execute the “PHP artisan list" command within the terminal. One will observe the command has been recorded. Command will be implemented with the sign that is kept in “protected $signature = ‘command: name'". One will observe the log message within the terminal.
• Utilize call back or closure method: Laravel permits one to close, execute a call back utilizing the “call" process. Laravel also permits one to schedule shell commands to initiate commands to the external applications and operating system.
• Simply after reaching the terminal add SSH to the server and cd within the project and execute the command "cronstab -e". This will ensure its opening and after pasting the code below within the file, save it and exit.

Some of the default ports that are forwarded to your Homestead environment are:

• SSH: 2222 → Forwards To 22.
• ngrok UI: 4040 → Forwards To 4040.
• HTTP: 8000 → Forwards To 80.
• HTTPS: 44300 → Forwards To 443.
• MySQL: 33060 → Forwards To 3306.
• PostgreSQL: 54320 → Forwards To 5432.
• MongoDB: 27017 → Forwards To 27017.

You can share your Homestead with others by using Vagrant Cloud by using the vagrant share command. It works with single-site setups only.

Yes, Homestead v6 or above versions support the multiple PHP Versions such that you can automatically get multiple PHP versions installed by default. The latest Laravel-Version with Homestead including PHP 5.6 is Laravel 5.6. These Homestead-Version supports PHP 5.6 to 7.3.

Multiple versions of PHP are supported in Homestead 6 on the same machine. In the Homestead.yaml file, the version of PHP needs to be specified before using it. The available versions of PHP are 7.1, 7.2 and 7.3.

Any of the Supported versions of PHP can be used through the CLI in the following way.

• Php7.1 artisan list
• Php7.2 artisan list
• Php7.3 artisan list

To configure network interfaces in Homestead, you can follow the given steps:

• Run the gist above to prove everything works fine.
• Create a .bashrc file like
• In your after.sh, source the .baschrc: 

cp /home/vagrant/Code/env/homestead/.bashrc ~/.bashrc

dos2unix ~/.bashrc

source ~/.bashrc

• Now running vagrant halt and then vagrant reload --provision

You update Homestead by following the given steps:

• Destroy your box and remove old version.
• Update VirtualBox to 5.1.10 with the extensions if needed.
• Update Vagrant to 1.9.1.
• Rename you Homestead directory to Homestead-0ld.
• Run vagrant box add laravel/homestead.
• Run vagrant up and that should be it.

There are several applications supported by Valet. Some of these are:

• Laravel
• Lumen
• Bedrock
• CakePHP 3
• Concrete5
• Contao
• Craft
• Drupal

Basically, Valet is a Laravel development environment for Mac minimalists that means it is a Mac-only application. Therefore you can say Valet does not supports windows or Ubuntu environment.

Before installing Valet fulfill these below requirements:

• Composer: One must install Composer before installing Valet.
• PHP: Before installing Valet install PHP if it is not installed.
• Carefully check whether one's system is not executing or running any programs or applications that bind port 80 similar to Nginx or Apache.

Now install Valet internationally with composer global require cretueusebiu/valet-windows.

Now configure Valet along with registration of Valet’s Daemon. This will launch Valet in an automated way on system setup.

Homebrew is an open-source software package management system for macOS and Linux. It helps Linux and macOS users for the installation of software in a simple manner. Homebrew is written in Ruby programming language and free to download.

You can install Valet by taking the given steps:

Step 1. Install Homebrew

Step 2. Install PHP

Step 3. Install MySQL

Step 4. Install Composer

Step 5. Install Valet: composer global require laravel/valet

Step 6. Serving Sites

You can uninstall the valet by removing the. vendor directory and the valet binary found in /usr/local/bin/valet. It will permanently remove Valet from your Mac.

There are different ways to configure a Vault server depending on the server. These are divided into the following categories:

• Command line flags are passed to the vault binary as part of the complete command line at runtime.
• Configuration files are read by the vault process at runtime and when reloaded by sending the process a hangup signal (SIGHUP).
• Environment variables are set in the environment for the shell of the user that executes the vault process and can only configure a limited set of options.

You can start Valet by following the given step:

• Install PHP using Homebrew
• Install the laravel/valet Composer package
• Run the valet install command.

Upgrading valet to v2 is simple and can be completed in just a few steps. First create a backup of your ~/.valet folder. Then uninstall your original:

• valet stop
• valet uninstall

Now, upgrade to the latest version of Valet. If you installed Valet via Composer, you should use the following command to update to the latest major version:

• composer global require laravel/valet

After the fresh Valet source code has been downloaded, you should run the install command:

• valet install
• valet restart

To serve sites on Valet, you will need to first configure a folder where Valet should search for your sites and the park command will register your current directory as a path that Valet should search for your sites.

In Valet, park and link are the two commands to help you serve your Laravel sites. park command lets you create a new directory on your Mac by running something like `mkdir ~/Sites`. Whereas The link command may also be used to serve your Laravel sites.

Securing sites with TLS is a function of valet. Basically, Valet serves sites over HTTP. However, if you would like to serve a site over encrypted TLS using HTTP/2, you may use the secure command.

Valet includes a command to share your local sites with the world. You can share it by :

• Sharing Sites Via Ngrok
• Sharing Sites Via Expose
• Sharing Sites Via Expose

Valet is a Laravel improvement environment for Mac essentialist. One can also share one's sites publicly utilizing local tunnels. It configures one's Mac to continue running Nginx in the framework when one's machine starts. Then utilizing DnsMasq Valet substitutes every appeal on the *.test domain to depict or point to websites installed in one's local machine.

Valet supports the following frameworks and cms:

• Static HTML. 
• Zend.
• WordPress.
• Laravel.
• Craft.
• Magento.
• Kirby. 
• Slim.
• Katana. 
• Bedrock. 
• Contao.
• Statamic. 
• Symfony.
• Concrete5.
• Jigsaw. 
• Joomla. 
• Lumen.
• OctoberCMS.

Laravel Request Lifecycle is as follows:

• Auto Loader
• Kernel
• Service Providers
• Dispatch Request
• Router

The php file or the bootstrap/start. php file is the first file that is loaded in Laravel. It creates the new Laravel Application object, which also serves as an IoC container.

The HTTP Kernel is used to process requests that come in through the web (HTTP) whereas the Console Kernel is used when you interact with your application from the command line.

A Service Container is also known as a dependency injection container which is simply a PHP object that manages the instantiation of services. It is a powerful tool for managing class dependencies and performing dependency injection.

To bind a service container to a service provide use App\Services\Transistor; use App\Services\PodcastParser; $this->app->bind(Transistor::class, function ($app) { return new Transistor($app->make(PodcastParser::class)); });

Sometimes one can have 2 classes that use a similar interface, but one wishes to administer various implementation within all classes. For instance, two controllers can depend on the various implementation of the Illuminate\Contracts\Filesystem\Filesystem Contract.

Laravel offers a simple and fluent assemblage for explaining this behavior. Thus, a contextual binding permits one to bind an execution to a selected class.

To resolve class instance out of the container in Laravel, for readability Laravel also offers an alias to the App::make method called makeWith which simply calls the make method behind the scenes. Know you can start resolving classes from the Container and have all their dependencies resolved automatically for you.

In automatic injection in laravel, the class dependencies are "injected" into the class via the constructor or, in some cases, "setter" methods.

You can write your own service provider in laravel with the help of service providers. In config/app. php file included with Laravel, you will see a provider array, these are all of the service provider classes that will be loaded for your application.

The Service Provider Register Method is used to declare all your service container bindings, with the help of the boot method, you can use already registered services via the register method.

To register your service provider in laravel, you just need to take a simple step i.e. add an entry to the array of service providers in the config/app. php file.

Deferred Providers in Laravel are every service provider class that will be packed for your implementation. Although more of these are “deferred” providers, explaining that they will be unloaded on all requests, only during the facilities their activities are required. Hence, if one's provider is only recording bindings in the Service Container, one can wish to defer its record until one of the recorded bindings is truly required. This will enhance the performance of the applications as it is not filled from the filesystem on all requests. To defer the filling of a provider, execute the \Illuminate\Contracts\Support\DeferrableProvider interface and explain a Provides procedure. The Provides process should send back the facility container bindings recorded by the provider.

To register a service provider via composer in Laravel using the register method.

Laravel Facades act as "static proxies" to the classes that already exist in the classes in the service container, it provides the benefit of an expressive syntax while maintaining more testability and the flexibility that is different from the traditional static methods. Lavarel provides many Facades and those Facades provide access to almost all the features of Lavarel. All the Facades of Lavarel are defined inside the namespace Illuminate\Support\Facades.

Facades use dynamic methods to proxy method calls to objects resolved from the service container, and we can test facades just as we would test an injected class instance. Whereas the dependency injection is the ability to swap implementations of the injected class.

getFacadeAccessor method is used to define what to resolve from the container in facade class.

Laravel's Contracts are basically a set of interfaces consists of various functionalities that define the core services provided by the framework.

Facades use dynamic methods to proxy method calls to objects resolved from the service container, and we can test facades just as we would test an injected class instance. Whereas Laravel's contracts are basically a set of interfaces consists of various functionalities that define the core services provided by the framework.

You can use \Redirect::to('/new-url', 301); for 301 redirects.

example :

Route::get('old-url', function(){ 
    return Redirect::to('/bar', 301); 
});

Named routes allow the convenient generation of URLs or redirects for specific routes. You may define a name for a path by chaining the name process onto the path definition.

Example

Route::get('user/registration', function () {
    //
})->name('registration');

To generate URLs from named Routes, follow the given steps:

• //Generating URLs.
• $url= route('student_details');
• //Generating Redirects...
• return redirect() -> route('student_details');

You can do subdomain routing in Laravel by using routes groups to achieve this: Route::group(array('domain' => '{subdomain}. website.com'), function () { Route::get('/', function ($subdomain) { $name = DB::table('users')->where('name', $subdomain)->get(); dd($name); }); });

Route prefixes are associated with routes by design in attribute routing. It is basically used to set a common prefix for an entire controller. It can be done by: Route::namespace('Admin') ->prefix('admin') ->name('admin. ') ->group(function () { Route::resource('users', 'UsersController'); })

To return a view from route in Laravel you can use: route. php Route::get("/page", function(){ return View::make("dir. page"); }); controller. php View::make("/page");

To configure route cache and clear route cache in Laravel, you can use the command: $ php artisan route:clear Route cache cleared!. If you want to cache your routes again, simply run the following command: $ php artisan route:cache Route cache cleared!.

To list all registered routes in Laravel application you can use php artisan route:list command or also use Route::getRoutes(); method it will return a RouteCollection.

Route Model Binding provides a mechanism to bind or inject a model instance in the route, and to validates, a model Id injected in the route by injecting a Model instance. In this, the model instance is directly injected bypassing the type hinted variable as a parameter in the closure.

In Implicit Binding, model instances are directly injected into the route or controller actions whose time-hinted variable names match a route segment name. Whereas in Explicit Binding the router’s model method specifies the class for a given parameter.

You can use url()->current(); method to get the current URL in Laravel Framework. This method returns only the URL without its parameter.If complete URLG with parameter is required then use url()->full();

Middleware in a Laravel is the bridge between the response and a request. Middleware is a type of mechanism for filtering. Middleware in Laravel verifies the authentication of the user. If the user is genuine, it redirects to the home page. If not, then the user is redirected to the login page. Each and Every middleware should be registered before using it. Parameters can also be passed through the middleware’s. The middleware is terminated after the response is sent to the browser.

There are two types of Middleware in Laravel. They are:

• Global Middle: It executes every Http request of an application
• Route Middleware: It is assigned to a particular route.

To create custom Middleware in Laravel you can follow the given steps:

• Create Custom Middleware.
• Add Route.
•  Add Method to Controller.

In Laravel, the middleware can be registered at app/Http/Kernel which contains two properties $middleware that is used to register Global Middleware and $routeMiddleware property that is used to register route specific middleware.

Yes, we can assign multiple middlewares to a route.

You can add a middleware in the route group by registering your middleware in the $routeMiddleware instead of the $middleware array.

Terminable middleware is implemented after the request has been run and before the response is ready. The response and request object inside a terminate method of the Terminable middleware is received, but the response cannot be changed it has been returned already. When the response is on the way to a browser, terminable middleware allows executing a middleware that is processed.

If a terminate method is defined in middleware and a web server is implying the Fast CGI method, then the terminate method will be automatically executed after the response is sent to a browser.

CSRF token protection can be applied to any HTML form in the Laravel application by specifying a hidden form field of the CSRF token.

You can exclude URLs from CSRF Protection in Laravel by defining it's routes outside of the web middleware group that is included in the default routes.php file or by adding the URIs to the $except property of the VerifyCsrfToken middleware.

X XSRF token is added to the request header for ajax requests. It is a type of malicious exploit of a website where unauthorized commands are submitted from a user that the web application trusts. Whereas CSRF is a one-click attack or session riding.

Controller in Laravel is a class in which is responsible for controlling application execution flow. It sits between Model and view. Most of the business logic are written in the controller. In Laravel controllers are kept in the app/Http/Controllers directory.

Example Controller In Laravel

<?php

namespace App\Http\Controllers;
use Illuminate\Support\Facades\Redirect;
use Illuminate\Http\Request;

class HomeController extends Controller
{
    /**
     * Create a new controller instance.
     *
     * @return void
     */
    public function __construct()
    {
       
    }

	public function index(Request $request){
		
				
	}
}

To create a controller in Laravel by extending the base controller class included with Laravel: App\Http\Controllers\Controller.

In Laravel, the middleware can be registered at app/Http/Kernel which contains two properties $middleware that is used to register Global Middleware and $routeMiddleware property that is used to register route specific middleware.

You can generate a controller with resources in Laravel by typing - PHP artisan makes: controller sharkController --resource. It will create a resource controller with all the methods in it.

To localize the create and edit action verbs, you may use the Route::resourceVerbs method. This may be done in the boot method of your AppServiceProvider:

You can do Dependency Injection in Laravel Controllers by following the given steps:

• public function __construct(Request $request)
• composer create-project laravel/laravel DI --prefer-dist.
• DB_CONNECTION=mysql DB_HOST=127.0. 0.1 DB_PORT=3306 DB_DATABASE=di DB_USERNAME=root DB_PASSWORD=mysql.
• php artisan make:seeder UsersTableSeeder.

Request::getPathInfo() is used to get requested path in Laravel.

In Laravel, we can use $request->ajax() method to check request is ajax or not.

Example:

      public function saveData(Request $request)
        {
            if($request->ajax()){
                return "Request is of Ajax Type";
            }
            return "Request is of Http type";
        }

You can retrieve all requested data in Laravel by using $request->all().

You can check whether an Input value is present or not in Laravel by running the following code:

if (Input::has('name'))

{

    //

}

Cookies are text files with small pieces of data that are used to identify your computer when you visit Internet sites. With the help of cookies::make() method to create or set cookies and With the help of Cookie::forget() method to delete or destroy cookies in Laravel.

To upload a file in Laravel 5 you can follow the given steps:

• Define Route
• Add Controller Function
• Add Blade File

Macros provide a way to add functionality to the classes wherein you do not have that function. It can help you to create a small reusable component that'll be possible to use it everywhere on your application.