Feature: add a new event for many-to-many relationships

app/Audit/AbstractAuditLogFormatter.php

@@ -3,6 +3,8 @@
 namespace App\Audit;
 
 use App\Audit\Utils\DateFormatter;
+use Doctrine\ORM\PersistentCollection;
+use Illuminate\Support\Facades\Log;
 
 /**
  * Copyright 2025 OpenStack Foundation
@@ -32,6 +34,90 @@ final public function setContext(AuditContext $ctx): void
         $this->ctx = $ctx;
     }
 
+
+    protected function processCollection(
+        mixed $owner,
+        mixed $col,
+        mixed $uow,
+        bool $isDeletion = false
+    ): ?array
+    {
+        if (!is_object($col) || !method_exists($col, 'getMapping') || !method_exists($col, 'getInsertDiff')) {
+            return null;
+        }
+
+        $mapping = $col->getMapping();
+
+        $addedEntities = $col->getInsertDiff();
+        $removedEntities = $col->getDeleteDiff();
+
+        $addedIds = $this->extractCollectionEntityIds($addedEntities);
+        $removedIds = $this->extractCollectionEntityIds($removedEntities);
+
+        if (empty($removedIds) && !empty($addedIds)) {
+            $this->recoverCollectionRemovalIds($uow, $owner, $mapping, $removedIds);
+        }
+
+        if (empty($addedIds) && empty($removedIds)) {
+            return null;
+        }
+
+        return [
+            'field'         => $mapping['fieldName'] ?? 'unknown',
+            'target_entity' => $mapping['targetEntity'] ?? null,
+            'is_deletion'   => $isDeletion,
+            'added_ids'     => $addedIds,
+            'removed_ids'   => $removedIds,
+            'join_table'    => $mapping['joinTable']['name'] ?? null,
+        ];
+    }
+
+    /**
+     * Recover removed IDs from original entity data
+     */
+    protected function recoverCollectionRemovalIds($uow, $owner, $mapping, &$removedIds): void
+    {
+        try {
+            $originalData = $uow->getOriginalEntityData($owner);
+            $fieldName = $mapping['fieldName'] ?? null;
+
+            if ($fieldName && isset($originalData[$fieldName])) {
+                $originalCollection = $originalData[$fieldName];
+                if ($originalCollection instanceof PersistentCollection || is_array($originalCollection)) {
+                    $originalEntities = is_array($originalCollection) 
+                        ? $originalCollection 
+                        : $originalCollection->toArray();
+                    $removedIds = $this->extractCollectionEntityIds($originalEntities);
+                }
+            }
+        } catch (\Exception $e) {
+            Log::warning('Failed to recover removed IDs from original entity data', [
+                'error' => $e->getMessage()
+            ]);
+        }
+    }
+
+    /**
+     * Extract IDs from entity objects in collection
+     */
+    protected function extractCollectionEntityIds(array $entities): array
+    {
+        $ids = [];
+        foreach ($entities as $entity) {
+            if (method_exists($entity, 'getId')) {
+                $id = $entity->getId();
+                if ($id !== null) {
+                    $ids[] = $id;
+                }
+            }
+        }
+
+        $uniqueIds = array_unique($ids);
+        sort($uniqueIds);
+
+        return array_values($uniqueIds);
+    }
+
     protected function getUserInfo(): string
     {
         if (app()->runningInConsole()) {

app/Audit/AuditEventListener.php

@@ -14,6 +14,8 @@
 
 use App\Audit\Interfaces\IAuditStrategy;
 use Doctrine\ORM\Event\OnFlushEventArgs;
+use Doctrine\ORM\Mapping\ClassMetadata;
+use Doctrine\ORM\PersistentCollection;
 use Illuminate\Support\Facades\App;
 use Illuminate\Support\Facades\Log;
 use Illuminate\Support\Facades\Route;
@@ -53,10 +55,14 @@ public function onFlush(OnFlushEventArgs $eventArgs): void
             foreach ($uow->getScheduledEntityDeletions() as $entity) {
                 $strategy->audit($entity, [], IAuditStrategy::EVENT_ENTITY_DELETION, $ctx);
             }
-
+            foreach ($uow->getScheduledCollectionDeletions() as $col) {
+                $this->auditCollection($col, $strategy, $ctx, $uow, true);
+            }
             foreach ($uow->getScheduledCollectionUpdates() as $col) {
-                $strategy->audit($col, [], IAuditStrategy::EVENT_COLLECTION_UPDATE, $ctx);
+                $this->auditCollection($col, $strategy, $ctx, $uow, false);
             }
+
+
         } catch (\Exception $e) {
             Log::error('Audit event listener failed', [
                 'error' => $e->getMessage(),
@@ -127,4 +133,41 @@ private function buildAuditContext(): AuditContext
             rawRoute:      $rawRoute
         );
     }
+
+
+    /**
+     * Audit collection changes
+     * Only determines if it's ManyToMany and emits appropriate event
+     */
+    private function auditCollection($subject, IAuditStrategy $strategy, AuditContext $ctx, $uow, bool $isDeletion = false): void
+    {
+        if (!$subject instanceof PersistentCollection) {
+            return;
+        }
+
+        $mapping = $subject->getMapping();
+        $isManyToMany = ($mapping['type'] ?? null) === ClassMetadata::MANY_TO_MANY;
+
+        if ($isManyToMany && empty($mapping['isOwningSide'])) {
+            return;
+        }
+
+        $owner = $subject->getOwner();
+        if ($owner === null) {
+            return;
+        }
+
+
+        $payload = [
+            'collection' => $subject,
+            'uow' => $uow,
+            'is_deletion' => $isDeletion,
+        ];
+
+        $eventType = $isManyToMany
+            ? ($isDeletion ? IAuditStrategy::EVENT_COLLECTION_MANYTOMANY_DELETE : IAuditStrategy::EVENT_COLLECTION_MANYTOMANY_UPDATE)
+            : IAuditStrategy::EVENT_COLLECTION_UPDATE;
+
+        $strategy->audit($owner, $payload, $eventType, $ctx);
+    }
 }

app/Audit/AuditLogFormatterFactory.php

@@ -107,6 +107,14 @@ public function make(AuditContext $ctx, $subject, string $event_type): ?IAuditLo
 
                 $formatter = new EntityCollectionUpdateAuditLogFormatter($child_entity_formatter);
                 break;
+            case IAuditStrategy::EVENT_COLLECTION_MANYTOMANY_UPDATE:
+            case IAuditStrategy::EVENT_COLLECTION_MANYTOMANY_DELETE:
+                $formatter = $this->getFormatterByContext($subject, $event_type, $ctx);
+                if(is_null($formatter)) {
+                    $child_entity_formatter = ChildEntityFormatterFactory::build($subject);
+                    $formatter = $child_entity_formatter;
+                }
+                break;
             case IAuditStrategy::EVENT_ENTITY_CREATION:
                 $formatter = $this->getFormatterByContext($subject, $event_type, $ctx);
                 if(is_null($formatter)) {

app/Audit/ConcreteFormatters/SummitAttendeeAuditLogFormatter.php

@@ -42,11 +42,85 @@ public function format($subject, array $change_set): ?string
 
                 case IAuditStrategy::EVENT_ENTITY_DELETION:
                     return sprintf("Attendee (%s) '%s' deleted by user %s", $id, $name, $this->getUserInfo());
+
+                case IAuditStrategy::EVENT_COLLECTION_MANYTOMANY_UPDATE:
+                    return $this->handleManyToManyCollection($subject, $change_set, $id, $name, false);
+
+                case IAuditStrategy::EVENT_COLLECTION_MANYTOMANY_DELETE:
+                    return $this->handleManyToManyCollection($subject, $change_set, $id, $name, true);
             }
         } catch (\Exception $ex) {
             Log::warning("SummitAttendeeAuditLogFormatter error: " . $ex->getMessage());
         }
 
         return null;
     }
+
+    private function handleManyToManyCollection(SummitAttendee $subject, array $change_set, $id, $name, bool $isDeletion): ?string
+    {
+        if (!isset($change_set['collection']) || !isset($change_set['uow'])) {
+            return null;
+        }
+
+        $col = $change_set['collection'];
+        $uow = $change_set['uow'];
+
+        $collectionData = $this->processCollection($subject, $col, $uow, $isDeletion);
+        if (!$collectionData) {
+            return null;
+        }
+
+        return $isDeletion
+            ? $this->formatManyToManyDelete($subject, $collectionData, $id, $name)
+            : $this->formatManyToManyUpdate($subject, $collectionData, $id, $name);
+    }
+
+    private function formatManyToManyUpdate(SummitAttendee $subject, array $collectionData, $id, $name): ?string
+    {
+        try {
+            $field = $collectionData['field'] ?? 'unknown';
+            $targetEntity = $collectionData['target_entity'] ?? 'unknown';
+            $added_ids = $collectionData['added_ids'] ?? [];
+
+            $ownerId = $subject->getId();
+
+            $description = sprintf(
+                "Attendee (%s), Field: %s, Target: %s, Added IDs: %s, by user %s",
+                $ownerId,
+                $field,
+                class_basename($targetEntity),
+                json_encode($added_ids),
+                $this->getUserInfo()
+            );
+
+            return $description;
+
+        } catch (\Exception $ex) {
+            Log::warning("SummitAttendeeAuditLogFormatter::formatManyToManyUpdate error: " . $ex->getMessage());
+            return sprintf("Attendee (%s) '%s' association updated by user %s", $id, $name, $this->getUserInfo());
+        }
+    }
+
+    private function formatManyToManyDelete(SummitAttendee $subject, array $collectionData, $id, $name): ?string
+    {
+        try {
+            $field = $collectionData['field'] ?? 'unknown';
+            $targetEntity = $collectionData['target_entity'] ?? 'unknown';
+            $removed_ids = $collectionData['removed_ids'] ?? [];
+
+            $description = sprintf(
+                "Attendee Delete: Field: %s, Target: %s, Cleared IDs: %s, by user %s",
+                $field,
+                class_basename($targetEntity),
+                json_encode($removed_ids),
+                $this->getUserInfo()
+            );
+
+            return $description;
+
+        } catch (\Exception $ex) {
+            Log::warning("SummitAttendeeAuditLogFormatter::formatManyToManyDelete error: " . $ex->getMessage());
+            return sprintf("Attendee (%s) '%s' association deleted by user %s", $id, $name, $this->getUserInfo());
+        }
+    }
 }

app/Audit/Interfaces/IAuditStrategy.php

@@ -33,6 +33,8 @@ public function audit($subject, array $change_set, string $event_type, AuditCont
     public const EVENT_ENTITY_CREATION = 'event_entity_creation';
     public const EVENT_ENTITY_DELETION = 'event_entity_deletion';
     public const EVENT_ENTITY_UPDATE = 'event_entity_update';
+    public const EVENT_COLLECTION_MANYTOMANY_UPDATE = 'event_collection_manytomany_update';
+    public const EVENT_COLLECTION_MANYTOMANY_DELETE = 'event_collection_manytomany_delete';
 
     public const ACTION_CREATE = 'create';
     public const ACTION_UPDATE = 'update';