Events API

Abstract base classes for strongly-typed event payloads in event-driven architecture.

What It Does

The Events API provides foundational abstract base classes for defining strongly-typed event payloads in a microservices architecture. It serves as the base layer for the Foundation’s event-driven system, enabling type-safe event handling for create, update, and delete operations.

Note: This package is marked as DEPRECATED but still widely used across the Foundation ecosystem at version 5.6.0.

Key Capabilities

Capability	Description
Typed Event Payloads	Generic abstract classes for create, update, and delete events
Type Safety	TypeScript support with generics for payload types
Consistency	Ensures uniform event structure across microservices
Extensibility	Allows services to extend with domain-specific event types
Integration	Foundation for event publishing and validation services

Base Event Classes

BaseCreatedEvent`<T>`

Represents entity creation events:

Contains payload of type Event<T>
Used when new entities are created
Triggers onCreate Cloud Functions

BaseUpdatedEvent`<T>`

Represents entity update events:

Contains payload of type UpdatedEvent<T>
Includes before/after values
Triggers onUpdate Cloud Functions

BaseDeletedEvent`<T>`

Represents entity deletion events:

Contains payload of type Event<T>
Used when entities are deleted
Triggers onDelete Cloud Functions

Event Structure

Events follow this structure:


{
  kind: 'event',
  item: any,          // Actual payload data
  timestamp: string,  // ISO timestamp
  senderId: string    // Triggering entity ID
}

Common Use Cases

Event-driven microservices: Base classes for domain events
Firestore triggers: Cloud Function event handling
Pub/Sub messaging: Type-safe event publishing
Event validation: Schema-based event validation
Audit trails: Track entity lifecycle events

What Customers Don’t Have to Build

Abstract event base classes
Event type definitions
Generic payload typing
Event structure consistency
Type-safe event inheritance