Add validation asserts to user entity

src/Entity/User.php

@@ -5,11 +5,15 @@ namespace App\Entity;
 use Symfony\Component\Security\Core\User\AdvancedUserInterface;
 use Doctrine\ORM\Mapping as ORM;
 use Doctrine\Common\Collections\ArrayCollection;
+use Symfony\Component\Validator\Constraints as Assert;
+use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
 use Serializable;
 
 /**
  * @ORM\Entity
  * @ORM\Table(name="user")
+ * @UniqueEntity("username")
+ * @UniqueEntity("email")
  */
 class User implements AdvancedUserInterface, Serializable
 {
@@ -22,6 +26,8 @@ class User implements AdvancedUserInterface, Serializable
 
     /**
      * @ORM\Column(type="string", length=80, unique=true)
+     * @Assert\NotBlank()
+     * 
      */
     protected $username;
 
@@ -33,6 +39,7 @@ class User implements AdvancedUserInterface, Serializable
     /**
      * @ORM\ManyToMany(targetEntity="Role", inversedBy="users")
      * @ORM\JoinTable(name="user_role")
+     * @Assert\NotBlank()
      */
     protected $roles;