Fix course creation

public/main/install/install.lib.php

@@ -2306,7 +2306,7 @@ function installSchemas($container, $upgrade = false)
 
     $urlRepo = $container->get(AccessUrlRepository::class);
     $accessUrl = $urlRepo->find(1);
-    if (!$accessUrl) {
+    if (null === $accessUrl) {
         $em = Database::getManager();
 
         // Creating AccessUrl

src/CoreBundle/Entity/AbstractResource.php

@@ -58,7 +58,7 @@ abstract class AbstractResource
     /**
      * @Groups({"resource_node:read", "resource_node:write", "document:read", "document:write"})
      */
-    public ?ResourceNode $parentResourceNode = null;
+    public ?int $parentResourceNode = 0;
 
     /**
      * @ApiProperty(iri="http://schema.org/image")
@@ -303,7 +303,7 @@ abstract class AbstractResource
 
     public function hasParentResourceNode(): bool
     {
-        return null !== $this->parentResourceNode;
+        return null !== $this->parentResourceNode && 0 !== $this->parentResourceNode;
     }
 
     public function setParentResourceNode($resourceNode): self

src/CoreBundle/Entity/Course.php

@@ -386,6 +386,7 @@ class Course extends AbstractResource implements ResourceInterface, ResourceWith
         $this->trackEAttempts = new ArrayCollection();
         $this->searchEngineRefs = new ArrayCollection();
         $this->templates = new ArrayCollection();
+        $this->activateLegal = 0;
         //$this->specificFieldValues = new ArrayCollection();
         //$this->sharedSurveys = new ArrayCollection();
     }

src/CoreBundle/Entity/Listener/ResourceListener.php

@@ -98,7 +98,7 @@ class ResourceListener
         }
 
         // Add resource node.
-        /** @var null|User $creator */
+        /** @var User|null $creator */
         $creator = $this->security->getUser();
 
         if (null === $creator) {