# Audit Log

## User Perspective
The Change History page (`/audit`) shows a chronological log of all user-initiated changes to the workspace. Useful for tracking who changed what and when.

Each entry shows: actor, entity type, entity ID, action (create/update/delete), timestamp, and before/after JSON snapshots (expandable).

## Developer Perspective

### AuditService
```typescript
AuditService.log(
  actorId: string,
  entityType: string,   // 'Video', 'Template', 'DescriptionBlock', etc.
  entityId: string,
  action: string,       // 'create', 'update', 'delete'
  before?: object,
  after?: object
)
```

### When to Log
Every user-facing mutation (create/update/delete) must call `AuditService.log()`. Background/system operations (queue processors, channel import) do NOT log.

### Adding Audit Logging to a Module
1. Import `AuditModule` in the module's `@Module({ imports: [...] })` array
2. Inject `AuditService` in the service constructor
3. Call `AuditService.log()` in each mutation method

### Tracked Entities
`Video`, `VideoConfig`, `DescriptionBlock`, `Template`, `Collaborator`, `TeamVariable`, `SavedView`, `TeamMember`

## Related
- [[02 - Backend]] (architecture)