Passing the newly generated security token to the event during user switching.

Event allows listeners to easily switch out the token if custom token updates are required

src/Symfony/Component/Security/CHANGELOG.md

@@ -4,6 +4,8 @@ CHANGELOG
 3.4.0
 -----
 
+ * added a `setToken()` method to the `SwitchUserEvent` class to allow to replace the created token while switching users
+   when custom token generation is required by application. 
  * Using voters that do not implement the `VoterInterface`is now deprecated in
    the `AccessDecisionManager` and this functionality will be removed in 4.0.
 

src/Symfony/Component/Security/Http/Event/SwitchUserEvent.php

@@ -12,6 +12,7 @@
 namespace Symfony\Component\Security\Http\Event;
 
 use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\Security\Core\Authentication\Token\TokenInterface;
 use Symfony\Component\Security\Core\User\UserInterface;
 use Symfony\Component\EventDispatcher\Event;
 
@@ -24,11 +25,13 @@ class SwitchUserEvent extends Event
 {
     private $request;
     private $targetUser;
+    private $token;
 
-    public function __construct(Request $request, UserInterface $targetUser)
+    public function __construct(Request $request, UserInterface $targetUser, TokenInterface $token = null)
     {
         $this->request = $request;
         $this->targetUser = $targetUser;
+        $this->token = $token;
     }
 
     /**
@@ -46,4 +49,17 @@ class SwitchUserEvent extends Event
     {
         return $this->targetUser;
     }
+
+    /**
+     * @return TokenInterface|null
+     */
+    public function getToken()
+    {
+        return $this->token;
+    }
+
+    public function setToken(TokenInterface $token)
+    {
+        $this->token = $token;
+    }
 }

src/Symfony/Component/Security/Http/Firewall/SwitchUserListener.php

@@ -145,8 +145,10 @@ class SwitchUserListener implements ListenerInterface
         $token = new UsernamePasswordToken($user, $user->getPassword(), $this->providerKey, $roles);
 
         if (null !== $this->dispatcher) {
-            $switchEvent = new SwitchUserEvent($request, $token->getUser());
+            $switchEvent = new SwitchUserEvent($request, $token->getUser(), $token);
             $this->dispatcher->dispatch(SecurityEvents::SWITCH_USER, $switchEvent);
+            // use the token from the event in case any listeners have replaced it.
+            $token = $switchEvent->getToken();
         }
 
         return $token;
@@ -169,8 +171,9 @@ class SwitchUserListener implements ListenerInterface
 
         if (null !== $this->dispatcher && $original->getUser() instanceof UserInterface) {
             $user = $this->provider->refreshUser($original->getUser());
-            $switchEvent = new SwitchUserEvent($request, $user);
+            $switchEvent = new SwitchUserEvent($request, $user, $original);
             $this->dispatcher->dispatch(SecurityEvents::SWITCH_USER, $switchEvent);
+            $original = $switchEvent->getToken();
         }
 
         return $original;

src/Symfony/Component/Security/Http/Tests/Firewall/SwitchUserListenerTest.php

@@ -227,4 +227,43 @@ class SwitchUserListenerTest extends TestCase
         $this->assertSame('page=3&section=2', $this->request->server->get('QUERY_STRING'));
         $this->assertInstanceOf('Symfony\Component\Security\Core\Authentication\Token\UsernamePasswordToken', $this->tokenStorage->getToken());
     }
+
+    public function testSwitchUserWithReplacedToken()
+    {
+        $user = new User('username', 'password', array());
+        $token = new UsernamePasswordToken($user, '', 'provider123', array('ROLE_FOO'));
+
+        $user = new User('replaced', 'password', array());
+        $replacedToken = new UsernamePasswordToken($user, '', 'provider123', array('ROLE_BAR'));
+
+        $this->tokenStorage->setToken($token);
+        $this->request->query->set('_switch_user', 'kuba');
+
+        $this->accessDecisionManager->expects($this->any())
+            ->method('decide')->with($token, array('ROLE_ALLOWED_TO_SWITCH'))
+            ->will($this->returnValue(true));
+
+        $this->userProvider->expects($this->any())
+            ->method('loadUserByUsername')->with('kuba')
+            ->will($this->returnValue($user));
+
+        $dispatcher = $this->getMockBuilder('Symfony\Component\EventDispatcher\EventDispatcherInterface')->getMock();
+        $dispatcher
+            ->expects($this->once())
+            ->method('dispatch')
+            ->with(SecurityEvents::SWITCH_USER,
+                $this->callback(function (SwitchUserEvent $event) use ($replacedToken, $user) {
+                    if ($user !== $event->getTargetUser()) {
+                        return false;
+                    }
+                    $event->setToken($replacedToken);
+
+                    return true;
+                }));
+
+        $listener = new SwitchUserListener($this->tokenStorage, $this->userProvider, $this->userChecker, 'provider123', $this->accessDecisionManager, null, '_switch_user', 'ROLE_ALLOWED_TO_SWITCH', $dispatcher);
+        $listener->handle($this->event);
+
+        $this->assertSame($replacedToken, $this->tokenStorage->getToken());
+    }
 }