Filter out LDAP users which are missing the identifier attribute

In case the identifier attribtue was missing we were defaulting to an empty string,
which (1) isn't really correct and (2) is not a valid identifier for api-platform
and makes it fail when serializig API responses.

Avoid this by ignoring all LDAP users without an identifier.

src/Service/LDAPApi.php

@@ -241,6 +241,9 @@ class LDAPApi implements LoggerAwareInterface, ServiceSubscriberInterface
         $persons = [];
         foreach ($this->getPeopleUserItems($currentPageNumber, $maxNumItemsPerPage, $options) as $userItem) {
             $person = $this->personFromUserItem($userItem, false);
+            if ($person === null) {
+                continue;
+            }
             $persons[] = $person;
         }
 
@@ -280,9 +283,15 @@ class LDAPApi implements LoggerAwareInterface, ServiceSubscriberInterface
         }
     }
 
-    public function personFromUserItem(User $user, bool $full): Person
+    /**
+     * Returns null in case the user is not a valid Person, for example if the identifier is missing.
+     */
+    public function personFromUserItem(User $user, bool $full): ?Person
     {
-        $identifier = $user->getFirstAttribute($this->identifierAttributeName) ?? '';
+        $identifier = $user->getFirstAttribute($this->identifierAttributeName);
+        if ($identifier === null) {
+            return null;
+        }
 
         $person = new Person();
         $person->setIdentifier($identifier);
@@ -339,6 +348,9 @@ class LDAPApi implements LoggerAwareInterface, ServiceSubscriberInterface
         } else {
             $user = $this->getPersonUserItem($id);
             $person = $this->personFromUserItem($user, true);
+            if ($person === null) {
+                throw ApiError::withDetails(Response::HTTP_NOT_FOUND, sprintf("Person with id '%s' could not be found!", $id));
+            }
         }
 
         return $person;

tests/PersonTest.php

@@ -106,4 +106,15 @@ class PersonTest extends ApiTestCase
 
         $this->assertEquals($person->getExtraData('test'), 'my-test-string');
     }
+
+    public function testPersonFromUserItemNoIdentifier()
+    {
+        $user = new AdldapUser([
+            'givenName' => ['givenName'],
+            'sn' => ['familyName'],
+        ], $this->newBuilder());
+
+        $person = $this->api->personFromUserItem($user, false);
+        $this->assertNull($person);
+    }
 }