Symfony Playground

This is a starter app from Symfony4 for easy forking for new starters.

Setup

1. Install Virtualbox
2. Install Vagrant
3. Run vagrant plugin install vagrant-hostsupdater
4. Run vagrant up

You now have a web server running on http://symfony.local.

Using the project

You can edit the code directly in this directory to make changes. You can ssh into the vagrant box with vagrant ssh. Get to the code with cd /srv/www/app/current. Once inside the vagrant box you can run Symfony commands, here are some useful ones:

# Clear the Symfony cache
$ bin/console cache:clear

Tasks

Homepage

1. Create a new Controller with an index action
2. Create a route in routes.yaml for the index action at the / path
3. Create a new twig template in templates/
4. Make the twig template extend base.html.twig
5. Make the index action render the new template
6. Pass some variables through to the twig template and render them
7. Play with adding new variables and removing them

Request parameters

1. Create a hello action in your Controller
2. Create a route for the action, give the route a path parameter of {name}
3. Add Request $request and string $name as parameters to the action
4. Get the lastName parameter from the $request with a suitable default value if it doesn't exist
5. Create a new twig template and pass the two names through to it
6. Make the twig template render the names
7. Play with the path and request parameters

Database entities

1. Create your database schema

   $ ./bin/console doctrine:database:create

2. Create a Post entity in Entity/
3. Give it the following attributes:
   • string id
   • string slug
   • string title
   • string text
   • \DateTimeImmutable $createdAt
   • \DateTimeImmutable $updatedAt
4. Import Doctrine\ORM\Mapping as ORM, these are the Doctrine annotations you'll use to define the schema
5. Add the @ORM\Entity annotation to the class
6. Add the @ORM\Column(type=<your type>) annotation to each property
   • Choose which type you want from the Doctrine docs
7. Add the following annotations to the id field to make MySQL automatically generate it:

   /**
    * @ORM\Id
    * @ORM\GeneratedValue(strategy="UUID")
    */

8. Check the SQL that Doctrine wants to run to update the database

   $ ./bin/console doctrine:schema:update --dump-sql

9. If the SQL makes sense, execute it

   $ ./bin/console doctrine:schema:update --force

10. Get the details to log into the database from the .env file

    DATABASE_URL=mysql://<username>:<password>@127.0.0.1:3306/<db name>
    

11. Log into the database

    $ mysql -u <username> -p <db name>

12. Have a play, here are some fun SQL commands

    show tables;
    describe post;
    select * from post;

Symfony forms

1. Create a PostType class in Form/ that extends AbstractType
2. Implement the buildForm(FormBuilderInterface $builder, array $options) function
3. Add a few fields to the form with $bulider->add() that exist in the Post entity, eg.

   $builder->add('title')

4. The second argument to the add() function allows you to change the type of the form field that's rendered

   $builder->add('text', TextareaType::class); 

5. Add a submit button to your form

   $builder->add('sumbit', SubmitType::class)

6. Create a new Controller action and route for createPost (remember to inject the Request)
7. In your controller, create a new Post, bind it to the form and handle the requsett

   $post = new Post();
   $form = $this->createForm(PostType::class, $post);
   $form->handleRequest($request)

8. Now create a new twig template 'create-post.html.twig' to render your form, you can render a form with:

   {{ form(form) }}

9. If the form hasn't been submitted, you need to render your new twig file

   if (false === $form->isSubmitted() || false === $form->isValid()) {
      return $this->>render('create-post.html.twig', ['form' => $form->createView()]);
   }

10. Now you can load your page and look at the form, have a play with the PostType class to see what you can change
11. In order to save your Post to the database when the form is submitted, you need to use the EntityManager, so you inject it into the constructor of your Controller

    /** @var EntityManagerInterface **/
    private $entityManager;
    
    public function __construct(EntityManagerInterface $entityManager)
    {
        $this->entityManager = $entityManagerInterface;
    }

12. Now you can save your Post to the database, but only if the form has been submitted and is valid

    $this->entityManager->persist($post);
    $this->entityManager->flush();

13. It's best practice to do a redirect after a form is successfully submitted because it prevents the user from accidentally submitting the form twice

    return $this->redirect('create');

14. Submit your form a few times, log into the database like we did in the previous task and check our your posts

Querying the Entity Manager

1. Create a new twig template that iterates through a list of Posts and prints their title

   <ul>
   {% for post in posts %}
      <li>{{ post.title }}</li>
   {% endfor %}
   </ul>

2. Create a new Controller action
3. Get a list of all the Posts and pass them through to your twig template

   $posts = $this->entityManager->findAll(Post::class);

4. Load the page, you should see a list of all the Posts in your database
5. Inject the Request into your action and get the 'title' parameter from it (with a sensible default value of '')
6. Create a QueryBuilder in order to search the database for specific Posts

   $posts = $this->entityManager->createQueryBuilder()
      ->select('post')
      ->from(Post:class, 'post')
      ->where('post.title = :title')
      ->setParameter('title', $title)
      ->getQuery()
      ->getResult()
   ;

7. Now you can search for Posts by title!
8. Have a play, try and the QueryBuilder doing a wildcard search with an SQL like