Symfony - Working Example

In this chapter, we will learn how to create a complete MVC based BookStore Application in Symfony Framework. Following are the steps.
Let’s create a new project named “BookStore” in Symfony using the following command.
symfony new BookStore

Create a BooksController in “src/AppBundle/Controller” directory. It is defined as follows.
<?php  
namespace AppBundle\Controller;  

use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route; 
use Symfony\Bundle\FrameworkBundle\Controller\Controller; 
use Symfony\Component\HttpFoundation\Response;  

class BooksController { 
   /** 
      * @Route("/books/author") 
   */ 
   public function authorAction() { 
      return new Response('Book store application!'); 
   } 
}
Now, we have created a BooksController, next create a view to render the action.
Let’s create a new folder named “Books” in “app/Resources/views/” directory. Inside the folder, create a file “author.html.twig” and add the following changes.
<h3> Simple book store application</h3> 

Now, render the view in BooksController class. It is defined as follows.
<?php  
namespace AppBundle\Controller;  

use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route; 
use Symfony\Bundle\FrameworkBundle\Controller\Controller; 
use Symfony\Component\HttpFoundation\Response;  

class BooksController extends Controller { 
   /** 
      * @Route("/books/author") 
   */ 
   public function authorAction() { 
      return $this->render('books/author.html.twig'); 
   } 
}
As of now, we have created a basic BooksController and the result is rendered. You can check the result in the browser using the URL “http://localhost:8000/books/author”.
Configure the database in “app/config/parameters.yml” file.
Open the file and add the following changes.
# This file is auto-generated during the composer install  
parameters: 
   database_driver: pdo_mysql 
   database_host: localhost 
   database_port: 3306 
   database_name: booksdb 
   database_user: <database_username> 
   database_password: <database_password> 
   mailer_transport: smtp 
   mailer_host: 127.0.0.1 
   mailer_user: null 
   mailer_password: null 
   secret: 0ad4b6d0676f446900a4cb11d96cf0502029620d 
   
   doctrine: 
      dbal: 
      driver:   pdo_mysql 
      host:     '%database_host%' 
      dbname:   '%database_name%' 
      user:     '%database_user%' 
      password: '%database_password%' 
      charset: utf8mb4 

Now, Doctrine can connect to your database “booksdb”.
Issue the following command to generate “booksdb” database. This step is used to bind the database in Doctrine.
php bin/console doctrine:database:create

After executing the command, it automatically generates an empty “booksdb” database. You can see the following response on your screen.
It will produce the following result −
Created database `booksdb` for connection named default 

Create a Book entity class inside the Entity directory which is located at “src/AppBundle/Entity”.
You can directly pass Book class using annotations. It is defined as follows.
Add the following code in the file.
<?php 
namespace AppBundle\Entity; 
use Doctrine\ORM\Mapping as ORM;  

/** 
   * @ORM\Entity 
   * @ORM\Table(name = "Books") 
*/  
class Book { 
   /** 
      * @ORM\Column(type = "integer") 
      * @ORM\Id 
      * @ORM\GeneratedValue(strategy = "AUTO") 
   */ 
   private $id;  
   
   /** 
      * @ORM\Column(type = "string", length = 50) 
   */ 
   private $name;  
    
   /** 
      * @ORM\Column(type = "string", length = 50) 
   */ 
      
   private $author;
   /** 
      * @ORM\Column(type = "decimal", scale = 2) 
   */ 
   private $price; 
}  
Here, the table name is optional.
If the table name is not specified, then it will be determined automatically based on the name of the entity class.
Doctrine creates simple entity classes for you. It helps you build any entity.
Issue the following command to generate an entity.
php bin/console doctrine:generate:entities AppBundle/Entity/Book

Then you will see the following result and the entity will be updated.
Generating entity "AppBundle\Entity\Book” 
   > backing up Book.php to Book.php~ 
   > generating AppBundle\Entity\Book 

<?php  
namespace AppBundle\Entity;  

use Doctrine\ORM\Mapping as ORM;  
/** 
   * @ORM\Entity 
   * @ORM\Table(name = "Books") 
*/ 
class Book { 
   /** 
      * @ORM\Column(type = "integer") 
      * @ORM\Id
      * @ORM\GeneratedValue(strategy = "AUTO") 
   */ 
   private $id;  
    
   /** 
      * @ORM\Column(type = "string", length = 50) 
   */ 
   private $name;  
    
   /** 
      * @ORM\Column(type = "string", length = 50) 
   */ 
   private $author;  
    
   /** 
      * @ORM\Column(type = "decimal", scale = 2) 
   */ 
   private $price;  
    
   /** 
      * Get id 
      * 
      * @return integer 
   */ 
   public function getId() { 
      return $this->id; 
   }  
   
   /** 
      * Set name 
      * 
      * @param string $name 
      * 
      * @return Book 
   */
   public function setName($name) { 
      $this->name = $name; 
      return $this; 
   }  
    
   /** 
      * Get name 
      * 
      * @return string 
   */ 
   public function getName() { 
      return $this->name; 
   }  
    
   /** 
      * Set author 
      * 
      * @param string $author 
      * 
      * @return Book 
   */ 
   public function setAuthor($author) { 
      $this->author = $author; 
      return $this; 
   }  
    
   /** 
      * Get author 
      * 
      * @return string 
   */ 
   public function getAuthor() {
      return $this->author; 
   }  
   
   /** 
      * Set price 
      * 
      * @param string $price 
      * 
      * @return Book 
   */ 
   public function setPrice($price) { 
      $this->price = $price; 
      return $this; 
   }  
    
   /** 
      * Get price 
      * 
      * @return string 
   */ 
   public function getPrice() { 
      return $this->price; 
   } 
}     
After creating entities, you should validate the mappings using the following command.
php bin/console doctrine:schema:validate 
It will produce the following result −
[Mapping]  OK - The mapping files are correct
[Database] FAIL - The database schema is not in sync with the current mapping file.

Since we have not created the Books table, the entity is out of sync. Let us create the Books table using Symfony command in the next step.
Doctrine can automatically create all the database tables needed for Book entity. This can be done using the following command.
php bin/console doctrine:schema:update --force

After executing the command, you will see the following response.
Updating database schema... 
Database schema updated successfully! "1" query was executed 

Now, again validate the schema using the following command.
php bin/console doctrine:schema:validate 

It will produce the following result −
[Mapping]  OK - The mapping files are correct. 
[Database] OK - The database schema is in sync with the mapping files. 

As seen in the Bind an Entity section, the following command generates all the getters and setters for the Book class.
$ php bin/console doctrine:generate:entities AppBundle/Entity/Book

Create a method in BooksController that will display the books’ details.
/** 
   * @Route("/books/display", name="app_book_display") 
*/ 
public function displayAction() { 
   $bk = $this->getDoctrine()
   ->getRepository('AppBundle:Book') 
   ->findAll(); 
   return $this->render('books/display.html.twig', array('data' => $bk)); 
}
Let’s create a view that points to display action. Move to the views directory and create file “display.html.twig”. Add the following changes in the file.
{% extends 'base.html.twig' %} 
{% block stylesheets %} 
   <style> 
      .table { border-collapse: collapse; } 
      .table th, td { 
         border-bottom: 1px solid #ddd; 
         width: 250px; 
         text-align: left; 
         align: left; 
      } 
   </style> 
{% endblock %}  
{% block body %} 
   <h2>Books database application!</h2>  
   <table class = "table">  
      <tr>  
         <th>Name</th>  
         <th>Author</th>  
         <th>Price</th>  
      </tr>  
      {% for x in data %} 
      <tr>  
         <td>{{ x.Name }}</td>   
         <td>{{ x.Author }}</td>
         <td>{{ x.Price }}</td>  
      </tr>  
      {% endfor %} 
   </table> 
{% endblock %}         
You can obtain the result by requesting the URL “http://localhost:8000/books/display” in the browser.
Let's create a functionality to add a book into the system. Create a new page, newAction method in the BooksController as follows.
// use section 
use Symfony\Component\HttpFoundation\Request; 
use Symfony\Component\Form\Extension\Core\Type\TextType; 
use Symfony\Component\Form\Extension\Core\Type\SubmitType;  

// methods section 
/** 
   * @Route("/books/new") 
*/ 

public function newAction(Request $request) { 
   $stud = new StudentForm();
      $form = $this->createFormBuilder($stud) 
         ->add('name', TextType::class) 
         ->add('author', TextType::class) 
         ->add('price', TextType::class) 
         ->add('save', SubmitType::class, array('label' => 'Submit')) 
         ->getForm();  
   return $this->render('books/new.html.twig', array('form' => $form->createView(),)); 
} 
Let’s create a view that points to a new action. Move to the views directory and create a file “new.html.twig”. Add the following changes in the file.
{% extends 'base.html.twig' %} 
{% block stylesheets %} 
   <style> 
      #simpleform { 
         width:600px; 
         border:2px solid grey; 
         padding:14px; 
      } 
      #simpleform label { 
         font-size:14px; 
         float:left; 
         width:300px; 
         text-align:right; 
         display:block; 
      } 
      #simpleform span { 
         font-size:11px; 
         color:grey;
         width:100px; 
         text-align:right; 
         display:block; 
      }  
      #simpleform input { 
         border:1px solid grey; 
         font-family:verdana; 
         font-size:14px; 
         color:light blue; 
         height:24px; 
         width:250px; 
         margin: 0 0 10px 10px; 
      }  
      #simpleform textarea { 
         border:1px solid grey; 
         font-family:verdana; 
         font-size:14px; 
         color:light blue; 
         height:120px; 
         width:250px; 
         margin: 0 0 20px 10px; 
      }  
      #simpleform select { 
         margin: 0 0 20px 10px; 
      } 
      #simpleform button { 
         clear:both; 
         margin-left:250px; 
         background: grey;
         color:#FFFFFF; 
         border:solid 1px #666666; 
         font-size:16px; 
      } 
   </style> 
{% endblock %}  
{% block body %} 
   <h3>Book details:</h3> 
   <div id = "simpleform"> 
      {{ form_start(form) }} 
      {{ form_widget(form) }} 
      {{ form_end(form) }} 
   </div> 
{% endblock %}    
It will produce the following screen as output −
Let's change the newAction method and include the code to handle form submission. Also, store the book information into the database.
/**
   * @Route("/books/new", name="app_book_new") 
*/ 
public function newAction(Request $request) { 
   $book = new Book(); 
   $form = $this->createFormBuilder($book) 
      ->add('name', TextType::class) 
      ->add('author', TextType::class) 
      ->add('price', TextType::class) 
      ->add('save', SubmitType::class, array('label' => 'Submit')) 
      ->getForm();  
   
   $form->handleRequest($request);  
   
   if ($form->isSubmitted() && $form->isValid()) { 
      $book = $form->getData(); 
      $doct = $this->getDoctrine()->getManager();  
      
      // tells Doctrine you want to save the Product 
      $doct->persist($book);  
      
      //executes the queries (i.e. the INSERT query) 
      $doct->flush();  
      
      return $this->redirectToRoute('app_book_display'); 
   } else { 
      return $this->render('books/new.html.twig', array( 
         'form' => $form->createView(), 
      )); 
   } 
}        
Once the book is stored into the database, redirect to the book display page.
To update the book, create an action, updateAction, and add the following changes.
/** 
   * @Route("/books/update/{id}", name = "app_book_update" ) 
*/ 
public function updateAction($id, Request $request) { 
   $doct = $this->getDoctrine()->getManager(); 
   $bk = $doct->getRepository('AppBundle:Book')->find($id);  
    
   if (!$bk) { 
      throw $this->createNotFoundException( 
         'No book found for id '.$id 
      ); 
   }  
   $form = $this->createFormBuilder($bk) 
      ->add('name', TextType::class) 
      ->add('author', TextType::class) 
      ->add('price', TextType::class) 
      ->add('save', SubmitType::class, array('label' => 'Submit')) 
      ->getForm();  
   
   $form->handleRequest($request);  
   
   if ($form->isSubmitted() && $form->isValid()) { 
      $book = $form->getData(); 
      $doct = $this->getDoctrine()->getManager();  
      
      // tells Doctrine you want to save the Product 
      $doct->persist($book);  
        
      //executes the queries (i.e. the INSERT query) 
      $doct->flush(); 
      return $this->redirectToRoute('app_book_display'); 
   } else {  
      return $this->render('books/new.html.twig', array(
         'form' => $form->createView(), 
      )); 
   } 
}        
Here, we are processing two functionalities. If the request only contains id, then we fetch it from the database and show it in the book form. And, if the request contains full book information, then we update the details in the database and redirect to the book display page.
Deleting an object requires a call to the remove() method of the entity (doctrine) manager.
This can be done using the following code.
/** 
   * @Route("/books/delete/{id}", name="app_book_delete") 
*/ 
public function deleteAction($id) { 
   $doct = $this->getDoctrine()->getManager(); 
   $bk = $doct->getRepository('AppBundle:Book')->find($id); 
   
   if (!$bk) { 
      throw $this->createNotFoundException('No book found for id '.$id); 
   } 
   $doct->remove($bk); 
   $doct->flush(); 
   return $this->redirectToRoute('app_book_display'); 
} 
Here, we deleted the book and redirected to book display page.
Now, update the body block in display view and include include add / edit / delete links as follows.
{% block body %} 
   <h2>Books database application!</h2> 
   <div> 
      <a href = "{{ path('app_book_new') }}">Add</a> 
   </div> 
   <table class = "table">  
      <tr>  
         <th>Name</th>  
         <th>Author</th>  
         <th>Price</th> 
         <th></th> 
         <th></th> 
      </tr>  
      {% for x in data %} 
      <tr>  
         <td>{{ x.Name }}</td>   
         <td>{{ x.Author }}</td>   
         <td>{{ x.Price }}</td>   
         <td><a href = "{{ path('app_book_update', { 'id' : x.Id }) }}">Edit</a></td>
         <td><a href = "{{ path('app_book_delete', { 'id' : x.Id }) }}">Delete</a></td>
      </tr>  
      {% endfor %} 
   </table>  
{% endblock %} 
It will produce the following screen as output −
Symfony comprises of a set of PHP components, an application framework, a community and a philosophy. Symfony is extremely flexible and capable of meeting all the requirements of advanced users, professionals, and an ideal choice for all the beginners with PHP.