medusa-store/www/apps/docs/content/references/services/classes/EventBusService.md

Class: EventBusService

Can keep track of multiple subscribers to different events and run the subscribers when events happen. Events will run asynchronously.

Hierarchy

• TransactionBaseService

  ↳ EventBusService

Implements

• IEventBusService

Constructors

constructor

• new EventBusService(__namedParameters, config, isSingleton?)

Parameters

Name	Type	Default value
__namedParameters	InjectedDependencies	undefined
config	any	undefined
isSingleton	boolean	true

Overrides

TransactionBaseService.constructor

Defined in

medusa/src/services/event-bus.ts:32

Properties

__configModule__

• Protected Optional Readonly __configModule__: Record<string, unknown>

Inherited from

TransactionBaseService.__configModule__

Defined in

medusa/src/interfaces/transaction-base-service.ts:14

---

__container__

• Protected Readonly __container__: any

Inherited from

TransactionBaseService.__container__

Defined in

medusa/src/interfaces/transaction-base-service.ts:13

---

__moduleDeclaration__

• Protected Optional Readonly __moduleDeclaration__: Record<string, unknown>

Inherited from

TransactionBaseService.__moduleDeclaration__

Defined in

medusa/src/interfaces/transaction-base-service.ts:15

---

config_

• Protected Readonly config_: ConfigModule

Defined in

medusa/src/services/event-bus.ts:24

---

enqueue_

• Protected enqueue_: Promise<void>

Defined in

medusa/src/services/event-bus.ts:30

---

eventBusModuleService_

• Protected Readonly eventBusModuleService_: IEventBusModuleService

Defined in

medusa/src/services/event-bus.ts:27

---

manager_

• Protected manager_: EntityManager

Inherited from

TransactionBaseService.manager_

Defined in

medusa/src/interfaces/transaction-base-service.ts:5

---

shouldEnqueuerRun

• Protected shouldEnqueuerRun: boolean

Defined in

medusa/src/services/event-bus.ts:29

---

stagedJobService_

• Protected Readonly stagedJobService_: StagedJobService

Defined in

medusa/src/services/event-bus.ts:25

---

transactionManager_

• Protected transactionManager_: undefined | EntityManager

Inherited from

TransactionBaseService.transactionManager_

Defined in

medusa/src/interfaces/transaction-base-service.ts:6

Accessors

activeManager_

• Protected get activeManager_(): EntityManager

Returns

EntityManager

Inherited from

TransactionBaseService.activeManager_

Defined in

medusa/src/interfaces/transaction-base-service.ts:8

Methods

atomicPhase_

▸ Protected atomicPhase_<TResult, TError>(work, isolationOrErrorHandler?, maybeErrorHandlerOrDontFail?): Promise<TResult>

Wraps some work within a transactional block. If the service already has a transaction manager attached this will be reused, otherwise a new transaction manager is created.

Type parameters

Name
TResult
TError

Parameters

Name	Type	Description
work	(transactionManager: EntityManager) => Promise<TResult>	the transactional work to be done
isolationOrErrorHandler?	IsolationLevel | (error: TError) => Promise<void | TResult>	the isolation level to be used for the work.
maybeErrorHandlerOrDontFail?	(error: TError) => Promise<void | TResult>	Potential error handler

Returns

Promise<TResult>

the result of the transactional work

Inherited from

TransactionBaseService.atomicPhase_

Defined in

medusa/src/interfaces/transaction-base-service.ts:56

---

emit

▸ emit<T>(data): Promise<void | StagedJob[]>

Calls all subscribers when an event occurs.

Type parameters

Name
T

Parameters

Name	Type	Description
data	EmitData<T>[]	The data to use to process the events

Returns

Promise<void | StagedJob[]>

the jobs from our queue

Implementation of

EventBusTypes.IEventBusService.emit

Defined in

medusa/src/services/event-bus.ts:112

▸ emit<T>(eventName, data, options?): Promise<void | StagedJob>

Calls all subscribers when an event occurs.

Type parameters

Name
T

Parameters

Name	Type	Description
eventName	string	the name of the event to be process.
data	T	the data to send to the subscriber.
options?	Record<string, unknown>	options to add the job with

Returns

Promise<void | StagedJob>

the job from our queue

Implementation of

EventBusTypes.IEventBusService.emit

Defined in

medusa/src/services/event-bus.ts:121

---

enqueuer_

▸ enqueuer_(): Promise<void>

Returns

Promise<void>

Defined in

medusa/src/services/event-bus.ts:185

---

shouldRetryTransaction_

▸ Protected shouldRetryTransaction_(err): boolean

Parameters

Name	Type
err	Record<string, unknown> | { code: string }

Returns

boolean

Inherited from

TransactionBaseService.shouldRetryTransaction_

Defined in

medusa/src/interfaces/transaction-base-service.ts:37

---

startEnqueuer

▸ startEnqueuer(): void

Returns

void

Defined in

medusa/src/services/event-bus.ts:175

---

stopEnqueuer

▸ stopEnqueuer(): Promise<void>

Returns

Promise<void>

Defined in

medusa/src/services/event-bus.ts:180

---

subscribe

▸ subscribe(event, subscriber, context?): EventBusService

Adds a function to a list of event subscribers.

Parameters

Name	Type	Description
event	string | symbol	the event that the subscriber will listen for.
subscriber	Subscriber<unknown>	the function to be called when a certain event happens. Subscribers must return a Promise.
context?	SubscriberContext	subscriber context

Returns

EventBusService

this

Implementation of

EventBusTypes.IEventBusService.subscribe

Defined in

medusa/src/services/event-bus.ts:78

---

unsubscribe

▸ unsubscribe(event, subscriber, context): EventBusService

Removes function from the list of event subscribers.

Parameters

Name	Type	Description
event	string | symbol	the event of the subcriber.
subscriber	Subscriber<unknown>	the function to be removed
context	SubscriberContext	subscriber context

Returns

EventBusService

this

Implementation of

EventBusTypes.IEventBusService.unsubscribe

Defined in

medusa/src/services/event-bus.ts:98

---

withTransaction

▸ withTransaction(transactionManager?): EventBusService

Parameters

Name	Type
transactionManager?	EntityManager

Returns

EventBusService

Implementation of

EventBusTypes.IEventBusService.withTransaction

Overrides

TransactionBaseService.withTransaction

Defined in

medusa/src/services/event-bus.ts:49