Files removed after cron run

I'm trying to get this to work, here's a patch, but its not quite right.

This will create a file_usage entry when you save the node the xAPI Package field is attached to.
Doing this, the file_managed record gets status=1

This code does not work on file delete / node save. The file_usage record is not deleted, the reference to the file is removed as normal, but the file is still status=1.

diff --git a/src/Plugin/Field/FieldType/XapiItem.php b/src/Plugin/Field/FieldType/XapiItem.php
index 99a889c..ee8dcfc 100644
--- a/src/Plugin/Field/FieldType/XapiItem.php
+++ b/src/Plugin/Field/FieldType/XapiItem.php
@@ -75,6 +75,10 @@ final class XapiItem extends FileItem {
     }
 
     $filesystem->remove($path);
+    // Delete file usage.
+    $file = $this->entity;
+    $entity_type = $this->getParent()->getEntity()->getEntityTypeId();
+    \Drupal::service('file.usage')->delete($file, 'lms_xapi', $entity_type, $this->getParent()->getEntity()->id());
   }
 
   /**
@@ -120,6 +124,49 @@ final class XapiItem extends FileItem {
     parent::preSave();
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function postSave($update) {
+    $entity = $this->getParent()->getEntity();
+    $entity_type = $entity->getEntityTypeId();
+    $file = $this->entity;
+
+    if (!$update) {
+      \Drupal::service('file.usage')->add($file, 'lms_xapi', $entity_type, $entity->id());
+    }
+    else {
+      if (!empty($entity->original) && $entity->getRevisionId() != $entity->original->getRevisionId()) {
+        \Drupal::service('file.usage')->add($file, 'lms_xapi', $entity->getEntityTypeId(), $entity->id());
+        return;
+      }
+      $ids = [$file->id()];
+      // Get the file IDs attached to the field before this update.
+      $field_name = $this->getFieldDefinition()->getName();
+      $original_ids = [];
+      $langcode = $this->getLangcode();
+      $original = $entity->original;
+      if ($original->hasTranslation($langcode)) {
+        $original_items = $original->getTranslation($langcode)->{$field_name};
+        foreach ($original_items as $item) {
+          $original_ids[] = $item->target_id;
+        }
+      }
+
+      // Decrement file usage by 1 for files that were removed from the field.
+      $removed_ids = array_filter(array_diff($original_ids, $ids));
+      $removed_files = \Drupal::entityTypeManager()->getStorage('file')->loadMultiple($removed_ids);
+      if (!empty($removed_files)) {
+        foreach ($removed_files as $file) {
+          \Drupal::service('file.usage')->delete($file, 'lms_xapi', $entity->getEntityTypeId(), $entity->id());
+        }
+      }
+      if (!in_array($file->id(), $original_ids)) {
+        \Drupal::service('file.usage')->add($file, 'lms_xapi', $entity->getEntityTypeId(), $entity->id());
+      }
+    }
+  }
+
   /**
    * Get full path of the extracted package.
    */

After patch, the status = 1

mysql> select * from node__field_xapi_package;
+--------------+---------+-----------+-------------+----------+-------+------------------------------+----------------------------+--------------------------------+
| bundle       | deleted | entity_id | revision_id | langcode | delta | field_xapi_package_target_id | field_xapi_package_display | field_xapi_package_description |
+--------------+---------+-----------+-------------+----------+-------+------------------------------+----------------------------+--------------------------------+
| xapi_package |       0 |      3393 |       15992 | en       |     0 |                        70211 |                          1 |                                |
+--------------+---------+-----------+-------------+----------+-------+------------------------------+----------------------------+--------------------------------+
1 row in set (0.00 sec)

mysql> select fid, status from file_managed where fid=70211;
+-------+--------+
| fid   | status |
+-------+--------+
| 70211 |      1 |
+-------+--------+
1 row in set (0.00 sec)

mysql> select * from file_usage where fid=70211;
+-------+----------+------+------+-------+
| fid   | module   | type | id   | count |
+-------+----------+------+------+-------+
| 70211 | lms_xapi | node | 3393 |     1 |
+-------+----------+------+------+-------+
1 row in set (0.01 sec)

It should manage replacing a file with another as well.

Your commit still doesn't work.

After uploading a file and saving the node, the record in the file_managed table has status=0
no file_usage records created.
The file is temporary and deleted on cron runs.

mysql> select * from file_usage where fid=69366;
Empty set (0.00 sec)
mysql> select fid, status from file_managed where fid=69366;
+-------+--------+
| fid   | status |
+-------+--------+
| 69366 |      0 |
+-------+--------+
1 row in set (0.00 sec)

Whoops never mind, had to clear those caches :) Thank you!