Symfony3安全性 - 从数据库加载用户不起作用

Question

我尝试从数据库加载用户时出现无效凭据错误。

这是我的 security.yml

security:
    providers:
        database:
            entity: { class: AppBundle\Entity\User, property: username  }

    encoders:
        AppBundle\Entity\User: plaintext

    firewalls:
        dev:
            pattern: ^/(_(profiler|wdt)|css|images|js)/
            security: false

        main:
            anonymous: ~
#            pattern: ^/
            form_login:
                login_path: /login
                check_path: /login_check
#                default_target_path: /admin
            provider: database

            logout:
                path: /logout
                target: /login

我的用户实体：

<?php

namespace AppBundle\Entity;

use Doctrine\ORM\Mapping as ORM;
use Symfony\Component\Security\Core\User\UserInterface;

/**
 * User
 *
 * @ORM\Table(name="user")
 * @ORM\Entity(repositoryClass="AppBundle\Repository\UserRepository")
 */
class User implements UserInterface
{
    /**
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     * @ORM\Column(type="integer")
     */
    private $id;

    /**
     *  @ORM\Column(type="string", unique=true)
     */
    private $username;

    /**
     * @ORM\Column(type="string")
     */
    private $password;

    /**
     * @return mixed
     */
    public function getId()
    {
        return $this->id;
    }

    /**
     * Returns the password used to authenticate the user.
     *
     * This should be the encoded password. On authentication, a plain-text
     * password will be salted, encoded, and then compared to this value.
     *
     * @return string The password
     */
    public function getPassword()
    {
        return $this->password;
    }

    /**
     * Set password
     *
     * @param string $password
     *
     * @return User
     */
    public function setPassword($password)
    {
        $this->password = $password;

        return $this;
    }

    /**
     * Returns the salt that was originally used to encode the password.
     *
     * This can return null if the password was not encoded using a salt.
     *
     * @return string|null The salt
     */
    public function getSalt()
    {
    }

    /**
     * Returns the username used to authenticate the user.
     *
     * @return string The username
     */
    public function getUsername()
    {
        return $this->getUsername();
    }

    /**
     * Set username
     *
     * @param string $username
     *
     * @return User
     */
    public function setUsername($username)
    {
        $this->username = $username;

        return $this;
    }

    /**
     * Removes sensitive data from the user.
     *
     * This is important if, at any given point, sensitive information like
     * the plain-text password is stored on this object.
     */
    public function eraseCredentials()
    {
        // TODO: Implement eraseCredentials() method.
    }

    /**
     * Returns the roles granted to the user.
     *
     * <code>
     * public function getRoles()
     * {
     *     return array('ROLE_USER');
     * }
     * </code>
     *
     * Alternatively, the roles might be stored on a ``roles`` property,
     * and populated in any number of different ways when the user object
     * is created.
     *
     * @return (Role|string)[] The user roles
     */
    public function getRoles()
    {
        // TODO: Implement getRoles() method.
    }
}

我的控制器：

    /**
     * @Route("/login", name="login")
     */
    public function loginAction(Request $request)
    {
        $authenticationUtils = $this->get('security.authentication_utils');

        // get the login error if there is one
        $error = $authenticationUtils->getLastAuthenticationError();

        // last username entered by the user
        $lastUsername = $authenticationUtils->getLastUsername();

        $form = $this->createForm(LoginType::class, array(
            '_username' => $lastUsername,
        ));

        return $this->render(':back/security:login.html.twig', array(
            'error'         => $error,
            'form'          => $form->createView(),
        ));
    }

    /**
     * @Route("/login_check", name="login_check")
     */
    public function loginCheckAction(){}

我不明白为什么它不起作用。我试图遵循文档并使其变得非常简单。

用户在我的数据库中，密码是纯文本。 我做错了什么？