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

[andrestejerina97]

ref: https://app.clickup.com/t/86b84w9x2

[andrestejerina97]

@martinquiroga-exo ready to review

[martinquiroga-exo]

LGTM

[martinquiroga-exo]

Not sure about this concatenated ternary operators, perhaps I would like to see an exit early guard clause when the event is an EVENT_COLLECTION_UPDATE.

I defer to Casey on this one since is a design issue rather than an implementation one.

[caseylocker]

I'm going to defer to whatever Seb comes up with but this is what I'm seeing.

The auditCollection() method changed the calling convention for all collection updates not just ManyToMany. For non-ManyToMany collections, it now passes $owner (the entity) as the subject instead of $col (the collection itself), and $payload instead of [] as the change set.

Both strategies downstream expect a PersistentCollection as $subject for EVENT_COLLECTION_UPDATE:

• OTLP strategy: instanceof PersistentCollection checks fail, formatter returns null, audit entries silently dropped
• DB strategy: calls count($subject) and $subject->getSnapshot() on the entity — throws \Error (not \Exception), uncaught by the catch block

Fix: Unless the intent was to actually change the behavior for all for some reason, only change the subject/payload for ManyToMany events; preserve the original $strategy->audit($col, [], EVENT_COLLECTION_UPDATE, $ctx) call for non-ManyToMany collections.

[andrestejerina97]

@caseylocker it's ready to review

[caseylocker]

Two fixes needed before merge:

1. app/Audit/AuditLogOtlpStrategy.php — Add M2M event mappings

mapEventTypeToAction() and getLogMessage() need explicit cases for EVENT_COLLECTION_MANYTOMANY_UPDATE (→ ACTION_COLLECTION_UPDATE / LOG_MESSAGE_COLLECTION_UPDATED) and EVENT_COLLECTION_MANYTOMANY_DELETE (→ ACTION_DELETE / LOG_MESSAGE_DELETED). Without this, M2M audit entries hit Elasticsearch with action=unknown, making them invisible to dashboards/queries filtering on action type.

buildAuditLogData() should also extract collection metadata from $change_set['collection'] for M2M events, since the subject is the owner entity (not a PersistentCollection).

2. app/Audit/AuditLogFormatterFactory.php — Fix generic M2M fallback

Lines 110-123: when no context-specific formatter exists, the fallback creates EntityCollectionUpdateAuditLogFormatter and passes the owner entity as $subject. That formatter calls $subject->getInsertDiff() (line 50 of EntityCollectionUpdateAuditLogFormatter), which doesn't exist on the owner entity. This either silently drops the audit entry or throws an uncaught \Error. The fallback should pass $change_set['collection'] as the subject instead of the owner, or use a M2M-aware generic formatter.

Why this blocks merge: Without fix 1, OTLP audit data is misclassified. Without fix 2, any M2M collection change on an entity without a registered custom formatter will silently fail or crash.