fix 502 gateway error on switch connection

src/Security/Voter/EntityVoter/AbstractEntityVoter.php

@@ -26,10 +26,12 @@ abstract class AbstractEntityVoter extends Voter
     protected const DELETE = 'DELETE';
 
     /**
-     * The current user if any, else null; access it trough isUserLoggedIn or getUser methods
-     * @var Access|null
+     * The current user if any; access it trough isUserLoggedIn or getUser methods
+     * If the current user is null, it has not been fetched already
+     * If it is false, there is no user logged in
+     * @var Access|null|false
      */
-    private ?Access $user = null;
+    private Access|null|false $user = null;
 
     /**
      * The supported class name. Override it in subclass.
@@ -54,31 +56,7 @@ abstract class AbstractEntityVoter extends Voter
         private InternalRequestsService $internalRequestsService,
         EntityManagerInterface $em,
         private SwitchUser $switchUser
-    ) {
-        /** @var Access $user */
-        $user = $this->security->getUser();
-
-        // <-- Special case of impersonated users: the switch user is not setup yet by symfony, we have to do it "manually"
-        $switchHeaderId = $_SERVER['HTTP_X_SWITCH_USER'] ?? null;
-        if ($switchHeaderId !== null) {
-            $switchAs = $em->find(Access::class, $switchHeaderId);
-            if (
-                $switchAs &&
-                (
-                    $this->security->isGranted('ROLE_ALLOWED_TO_SWITCH') ||
-                    $this->switchUser->isAllowedToSwitch($user, $switchAs)
-                )
-            ) {
-                $user = $switchAs;
-            }
-        }
-        // -->
-
-        // If the user is not anonymous, remember it
-        if ($user instanceof Access) {
-            $this->user = $user;
-        }
-    }
+    ) {}
 
     /**
      * Default `supports` method, that uses self::entityClass and self::allowedOperations to determine if the voter
@@ -164,7 +142,31 @@ abstract class AbstractEntityVoter extends Voter
      * @return Access
      */
     protected function getUser(): ?Access {
-        return $this->user;
+        if ($this->user === null) {
+            /** @var Access $user */
+            $user = $this->security->getUser();
+
+            // <-- Special case of impersonated users: the switch user is not setup yet by symfony, we have to do it "manually"
+            $switchHeaderId = $_SERVER['HTTP_X_SWITCH_USER'] ?? null;
+            if ($switchHeaderId !== null) {
+                $switchAs = $this->em->find(Access::class, $switchHeaderId);
+                if (
+                    $switchAs &&
+                    (
+                        $this->security->isGranted('ROLE_ALLOWED_TO_SWITCH') ||
+                        $this->switchUser->isAllowedToSwitch($user, $switchAs)
+                    )
+                ) {
+                    $user = $switchAs;
+                }
+            }
+            // -->
+
+            // If the user is not anonymous, remember it
+            $this->user = $user instanceof Access ? $user : false;
+        }
+
+        return $this->user !== false ? $this->user : null;
     }
 
     /**