es cqrs.Event

Interface: Event

es-cqrs.Event

Event interface

In order for the event-store to replay your events implement the Event interface and create a constructor according to EventConstructor, or for conveniency extend the DefaultEvent class:

constructor(
  public readonly aggregateId: string,
  public readonly aggregateType: string,
  public readonly revision: number,
  public readonly createdAt: Date,
  public readonly userId: string,
  public readonly data: {[key: string]: any}
)

It is recommended to define data as an interface with the event

Example:

import { Event } from '@sclable/es-cqrs'

interface EventData {
  accountName: string,
  email: string,
  birthday: Date,
}

export class AccountCreatedEvent implements Event {
  public constructor(
    public readonly aggregateId: string,
    public readonly aggregateType: string,
    public readonly revision: number,
    public readonly createdAt: Date,
    public readonly userId: string,
    public readonly data: EventData,
  ) {}
}

To use CustomEventOptions define that as the forth parameter

Example:

@EventForModule('MyModule')
export class AccountCreatedEvent implements Event {
  public constructor(
    public readonly aggregateId: string,
    public readonly aggregateType: string,
    public readonly revision: number,
    public readonly createdAt: Date,
    public readonly userId: string,
    public readonly data: EventData,
    public readonly custom: CustomEventOptions,
  ) {}
}

Or use it as a computed parameter

Example:

@EventForModule('MyModule')
export class AccountCreatedEvent implements Event {
  public constructor(
    public readonly aggregateId: string,
    public readonly aggregateType: string,
    public readonly revision: number,
    public readonly createdAt: Date,
    public readonly userId: string,
    public readonly data: EventData,
    public readonly custom: CustomEventOptions = { queueById: data.customId }
  ) {}
}

To handle these events implement the IEventHandler interface.

Example:

import { EventHandler, IEventHandler } from '@sclable/es-cqrs'
import { AccountCreatedEvent } from './events'

@EventHandler(AccountCreatedEvent)
export class AccountCreatedEventHandler implements IEventHandler<AccountCreatedEvent> {
  async handle(event: AccountCreatedEvent) {
    // do something (e.g. change DB, change view, emit to other type of listeners)
  }
}

Hierarchy

• IEvent

  ↳ Event

Implemented by

• DefaultEvent

Table of contents

Properties

• aggregateId
• aggregateType
• createdAt
• customOptions
• data
• revision
• userId

Properties

aggregateId

• aggregateId: string

Defined in

packages/es-cqrs/src/interfaces/event.ts:96

---

aggregateType

• aggregateType: string

Defined in

packages/es-cqrs/src/interfaces/event.ts:97

---

createdAt

• createdAt: Date

Defined in

packages/es-cqrs/src/interfaces/event.ts:99

---

customOptions

• Optional customOptions: CustomEventOptions

Defined in

packages/es-cqrs/src/interfaces/event.ts:103

---

data

• data: any

Defined in

packages/es-cqrs/src/interfaces/event.ts:102

---

revision

• revision: number

Defined in

packages/es-cqrs/src/interfaces/event.ts:98

---

userId

• userId: string

Defined in

packages/es-cqrs/src/interfaces/event.ts:100