From 75eaa5a82a45be190300b677f348acd5a690a7bb Mon Sep 17 00:00:00 2001
From: jannisp <jannisp@student.ethz.ch>
Date: Thu, 22 Apr 2021 15:20:02 +0200
Subject: [PATCH] setup login form

---
 config/packages/security.yaml         |   7 ++
 src/Controller/SecurityController.php |  36 +++++++++
 src/Security/AppAuthenticator.php     | 106 ++++++++++++++++++++++++++
 templates/security/login.html.twig    |  42 ++++++++++
 4 files changed, 191 insertions(+)
 create mode 100644 src/Controller/SecurityController.php
 create mode 100644 src/Security/AppAuthenticator.php
 create mode 100644 templates/security/login.html.twig

diff --git a/config/packages/security.yaml b/config/packages/security.yaml
index f0af4c7..b0aff30 100644
--- a/config/packages/security.yaml
+++ b/config/packages/security.yaml
@@ -18,6 +18,13 @@ security:
             anonymous: true
             lazy: true
             provider: app_user_provider
+            guard:
+                authenticators:
+                    - App\Security\AppAuthenticator
+            logout:
+                path: app_logout
+                # where to redirect after logout
+                # target: app_any_route
 
             # activate different ways to authenticate
             # https://symfony.com/doc/current/security.html#firewalls-authentication
diff --git a/src/Controller/SecurityController.php b/src/Controller/SecurityController.php
new file mode 100644
index 0000000..ed5a595
--- /dev/null
+++ b/src/Controller/SecurityController.php
@@ -0,0 +1,36 @@
+<?php
+
+namespace App\Controller;
+
+use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
+use Symfony\Component\HttpFoundation\Response;
+use Symfony\Component\Routing\Annotation\Route;
+use Symfony\Component\Security\Http\Authentication\AuthenticationUtils;
+
+class SecurityController extends AbstractController
+{
+    /**
+     * @Route("/login", name="app_login")
+     */
+    public function login(AuthenticationUtils $authenticationUtils): Response
+    {
+        // if ($this->getUser()) {
+        //     return $this->redirectToRoute('target_path');
+        // }
+
+        // get the login error if there is one
+        $error = $authenticationUtils->getLastAuthenticationError();
+        // last username entered by the user
+        $lastUsername = $authenticationUtils->getLastUsername();
+
+        return $this->render('security/login.html.twig', ['last_username' => $lastUsername, 'error' => $error]);
+    }
+
+    /**
+     * @Route("/logout", name="app_logout")
+     */
+    public function logout()
+    {
+        throw new \LogicException('This method can be blank - it will be intercepted by the logout key on your firewall.');
+    }
+}
diff --git a/src/Security/AppAuthenticator.php b/src/Security/AppAuthenticator.php
new file mode 100644
index 0000000..f534e89
--- /dev/null
+++ b/src/Security/AppAuthenticator.php
@@ -0,0 +1,106 @@
+<?php
+
+namespace App\Security;
+
+use App\Entity\User;
+use Doctrine\ORM\EntityManagerInterface;
+use Symfony\Component\HttpFoundation\RedirectResponse;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\Routing\Generator\UrlGeneratorInterface;
+use Symfony\Component\Security\Core\Authentication\Token\TokenInterface;
+use Symfony\Component\Security\Core\Encoder\UserPasswordEncoderInterface;
+use Symfony\Component\Security\Core\Exception\CustomUserMessageAuthenticationException;
+use Symfony\Component\Security\Core\Exception\InvalidCsrfTokenException;
+use Symfony\Component\Security\Core\Security;
+use Symfony\Component\Security\Core\User\UserInterface;
+use Symfony\Component\Security\Core\User\UserProviderInterface;
+use Symfony\Component\Security\Csrf\CsrfToken;
+use Symfony\Component\Security\Csrf\CsrfTokenManagerInterface;
+use Symfony\Component\Security\Guard\Authenticator\AbstractFormLoginAuthenticator;
+use Symfony\Component\Security\Guard\PasswordAuthenticatedInterface;
+use Symfony\Component\Security\Http\Util\TargetPathTrait;
+
+class AppAuthenticator extends AbstractFormLoginAuthenticator implements PasswordAuthenticatedInterface
+{
+    use TargetPathTrait;
+
+    public const LOGIN_ROUTE = 'app_login';
+
+    private $entityManager;
+    private $urlGenerator;
+    private $csrfTokenManager;
+    private $passwordEncoder;
+
+    public function __construct(EntityManagerInterface $entityManager, UrlGeneratorInterface $urlGenerator, CsrfTokenManagerInterface $csrfTokenManager, UserPasswordEncoderInterface $passwordEncoder)
+    {
+        $this->entityManager = $entityManager;
+        $this->urlGenerator = $urlGenerator;
+        $this->csrfTokenManager = $csrfTokenManager;
+        $this->passwordEncoder = $passwordEncoder;
+    }
+
+    public function supports(Request $request)
+    {
+        return self::LOGIN_ROUTE === $request->attributes->get('_route')
+            && $request->isMethod('POST');
+    }
+
+    public function getCredentials(Request $request)
+    {
+        $credentials = [
+            'email' => $request->request->get('email'),
+            'password' => $request->request->get('password'),
+            'csrf_token' => $request->request->get('_csrf_token'),
+        ];
+        $request->getSession()->set(
+            Security::LAST_USERNAME,
+            $credentials['email']
+        );
+
+        return $credentials;
+    }
+
+    public function getUser($credentials, UserProviderInterface $userProvider)
+    {
+        $token = new CsrfToken('authenticate', $credentials['csrf_token']);
+        if (!$this->csrfTokenManager->isTokenValid($token)) {
+            throw new InvalidCsrfTokenException();
+        }
+
+        $user = $this->entityManager->getRepository(User::class)->findOneBy(['email' => $credentials['email']]);
+
+        if (!$user) {
+            // fail authentication with a custom error
+            throw new CustomUserMessageAuthenticationException('Email could not be found.');
+        }
+
+        return $user;
+    }
+
+    public function checkCredentials($credentials, UserInterface $user)
+    {
+        return $this->passwordEncoder->isPasswordValid($user, $credentials['password']);
+    }
+
+    /**
+     * Used to upgrade (rehash) the user's password automatically over time.
+     */
+    public function getPassword($credentials): ?string
+    {
+        return $credentials['password'];
+    }
+
+    public function onAuthenticationSuccess(Request $request, TokenInterface $token, string $providerKey)
+    {
+        if ($targetPath = $this->getTargetPath($request->getSession(), $providerKey)) {
+            return new RedirectResponse($targetPath);
+        }
+
+        return new RedirectResponse($this->urlGenerator->generate('logout'));
+    }
+
+    protected function getLoginUrl()
+    {
+        return $this->urlGenerator->generate(self::LOGIN_ROUTE);
+    }
+}
diff --git a/templates/security/login.html.twig b/templates/security/login.html.twig
new file mode 100644
index 0000000..d461ea2
--- /dev/null
+++ b/templates/security/login.html.twig
@@ -0,0 +1,42 @@
+{% extends 'base.html.twig' %}
+
+{% block title %}Log in!{% endblock %}
+
+{% block body %}
+<form method="post">
+    {% if error %}
+        <div class="alert alert-danger">{{ error.messageKey|trans(error.messageData, 'security') }}</div>
+    {% endif %}
+
+    {% if app.user %}
+        <div class="mb-3">
+            You are logged in as {{ app.user.username }}, <a href="{{ path('app_logout') }}">Logout</a>
+        </div>
+    {% endif %}
+
+    <h1 class="h3 mb-3 font-weight-normal">Please sign in</h1>
+    <label for="inputEmail">Email</label>
+    <input type="email" value="{{ last_username }}" name="email" id="inputEmail" class="form-control" required autofocus>
+    <label for="inputPassword">Password</label>
+    <input type="password" name="password" id="inputPassword" class="form-control" required>
+
+    <input type="hidden" name="_csrf_token"
+           value="{{ csrf_token('authenticate') }}"
+    >
+
+    {#
+        Uncomment this section and add a remember_me option below your firewall to activate remember me functionality.
+        See https://symfony.com/doc/current/security/remember_me.html
+
+        <div class="checkbox mb-3">
+            <label>
+                <input type="checkbox" name="_remember_me"> Remember me
+            </label>
+        </div>
+    #}
+
+    <button class="btn btn-lg btn-primary" type="submit">
+        Sign in
+    </button>
+</form>
+{% endblock %}