Add a pool option to register a message listener on pool workers (#487)

[poolifier.git] / src / pools / abstract-pool.ts

diff --git a/src/pools/abstract-pool.ts b/src/pools/abstract-pool.ts
index e0aa1810c4d839f39d29eee350ae010a6945ffab..f3a8c1c6c9a7bb0a730b6b3b10dcd9a766b64e5e 100644 (file)
--- a/src/pools/abstract-pool.ts
+++ b/src/pools/abstract-pool.ts
@@ -12,6 +12,11 @@ import {
   WorkerChoiceStrategyContext
 } from './selection-strategies'
 
+/**
+ * Callback invoked if the worker has received a message.
+ */
+export type MessageHandler<Worker> = (this: Worker, m: unknown) => void
+
 /**
  * Callback invoked if the worker raised an error.
  */
@@ -31,6 +36,13 @@ export type ExitHandler<Worker> = (this: Worker, code: number) => void
  * Basic interface that describes the minimum required implementation of listener events for a pool-worker.
  */
 export interface IWorker {
+  /**
+   * Register a listener to the message event.
+   *
+   * @param event `'message'`.
+   * @param handler The message handler.
+   */
+  on(event: 'message', handler: MessageHandler<this>): void
   /**
    * Register a listener to the error event.
    *
@@ -65,6 +77,10 @@ export interface IWorker {
  * Options for a poolifier pool.
  */
 export interface PoolOptions<Worker> {
+  /**
+   * A function that will listen for message event on each worker.
+   */
+  messageHandler?: MessageHandler<Worker>
   /**
    * A function that will listen for error event on each worker.
    */
@@ -84,7 +100,7 @@ export interface PoolOptions<Worker> {
   /**
    * Pool events emission.
    *
-   * Default to true.
+   * @default true
    */
   enableEvents?: boolean
 }
@@ -295,7 +311,7 @@ export abstract class AbstractPool<
   protected abstract isMain (): boolean
 
   /**
-   * Increase the number of tasks that the given workers has applied.
+   * Increase the number of tasks that the given worker has applied.
    *
    * @param worker Worker whose tasks are increased.
    */
@@ -304,7 +320,7 @@ export abstract class AbstractPool<
   }
 
   /**
-   * Decrease the number of tasks that the given workers has applied.
+   * Decrease the number of tasks that the given worker has applied.
    *
    * @param worker Worker whose tasks are decreased.
    */
@@ -313,7 +329,7 @@ export abstract class AbstractPool<
   }
 
   /**
-   * Step the number of tasks that the given workers has applied.
+   * Step the number of tasks that the given worker has applied.
    *
    * @param worker Worker whose tasks are set.
    * @param step Worker number of tasks step.
@@ -403,6 +419,7 @@ export abstract class AbstractPool<
   protected createAndSetupWorker (): Worker {
     const worker: Worker = this.createWorker()
 
+    worker.on('message', this.opts.messageHandler ?? EMPTY_FUNCTION)
     worker.on('error', this.opts.errorHandler ?? EMPTY_FUNCTION)
     worker.on('online', this.opts.onlineHandler ?? EMPTY_FUNCTION)
     worker.on('exit', this.opts.exitHandler ?? EMPTY_FUNCTION)