refactor: factor out async function detection helper

[poolifier.git] / src / worker / abstract-worker.ts

diff --git a/src/worker/abstract-worker.ts b/src/worker/abstract-worker.ts
index 76a7ee70ba96a93e6a92934a6b9cc54d81dbe821..7d81a88ccc816803bcdcdae4f89cb9dd56486f51 100644 (file)
--- a/src/worker/abstract-worker.ts
+++ b/src/worker/abstract-worker.ts
@@ -7,7 +7,7 @@ import type {
   TaskPerformance,
   WorkerStatistics
 } from '../utility-types'
-import { EMPTY_FUNCTION, isPlainObject } from '../utils'
+import { EMPTY_FUNCTION, isAsyncFunction, isPlainObject } from '../utils'
 import {
   type KillBehavior,
   KillBehaviors,
@@ -28,14 +28,18 @@ const DEFAULT_KILL_BEHAVIOR: KillBehavior = KillBehaviors.SOFT
  * Base class that implements some shared logic for all poolifier workers.
  *
  * @typeParam MainWorker - Type of main worker.
- * @typeParam Data - Type of data this worker receives from pool's execution. This can only be serializable data.
- * @typeParam Response - Type of response the worker sends back to the main worker. This can only be serializable data.
+ * @typeParam Data - Type of data this worker receives from pool's execution. This can only be structured-cloneable data.
+ * @typeParam Response - Type of response the worker sends back to the main worker. This can only be structured-cloneable data.
  */
 export abstract class AbstractWorker<
   MainWorker extends Worker | MessagePort,
   Data = unknown,
   Response = unknown
 > extends AsyncResource {
+  /**
+   * Worker id.
+   */
+  protected abstract id: number
   /**
    * Task function(s) processed by the worker when the pool's `execution` function is invoked.
    */
@@ -45,7 +49,7 @@ export abstract class AbstractWorker<
    */
   protected lastTaskTimestamp!: number
   /**
-   * Performance statistics computation.
+   * Performance statistics computation requirements.
    */
   protected statistics!: WorkerStatistics
   /**
@@ -67,7 +71,7 @@ export abstract class AbstractWorker<
     taskFunctions:
     | WorkerFunction<Data, Response>
     | TaskFunctions<Data, Response>,
-    protected mainWorker: MainWorker | undefined | null,
+    protected readonly mainWorker: MainWorker,
     protected readonly opts: WorkerOptions = {
       /**
        * The kill behavior option on this worker or its default value.
@@ -90,8 +94,8 @@ export abstract class AbstractWorker<
         (this.opts.maxInactiveTime ?? DEFAULT_MAX_INACTIVE_TIME) / 2
       )
       this.checkAlive.bind(this)()
+      this.mainWorker?.on('message', this.messageListener.bind(this))
     }
-    this.mainWorker?.on('message', this.messageListener.bind(this))
   }
 
   private checkWorkerOptions (opts: WorkerOptions): void {
@@ -146,27 +150,22 @@ export abstract class AbstractWorker<
    *
    * @param message - Message received.
    */
-  protected messageListener (
-    message: MessageValue<Data, Data, MainWorker>
-  ): void {
+  protected messageListener (message: MessageValue<Data, Data>): void {
     if (message.id != null && message.data != null) {
       // Task message received
       const fn = this.getTaskFunction(message.name)
-      if (fn?.constructor.name === 'AsyncFunction') {
+      if (isAsyncFunction(fn)) {
         this.runInAsyncScope(this.runAsync.bind(this), this, fn, message)
       } else {
         this.runInAsyncScope(this.runSync.bind(this), this, fn, message)
       }
-    } else if (message.parent != null) {
-      // Main worker reference message received
-      this.mainWorker = message.parent
+    } else if (message.statistics != null) {
+      // Statistics message received
+      this.statistics = message.statistics
     } else if (message.kill != null) {
       // Kill message received
       this.aliveInterval != null && clearInterval(this.aliveInterval)
       this.emitDestroy()
-    } else if (message.statistics != null) {
-      // Statistics message received
-      this.statistics = message.statistics
     }
   }
 
@@ -177,7 +176,7 @@ export abstract class AbstractWorker<
    */
   protected getMainWorker (): MainWorker {
     if (this.mainWorker == null) {
-      throw new Error('Main worker was not set')
+      throw new Error('Main worker not set')
     }
     return this.mainWorker
   }
@@ -207,10 +206,10 @@ export abstract class AbstractWorker<
    * Handles an error and convert it to a string so it can be sent back to the main worker.
    *
    * @param e - The error raised by the worker.
-   * @returns Message of the error.
+   * @returns The error message.
    */
   protected handleError (e: Error | string): string {
-    return e as string
+    return e instanceof Error ? e.message : e
   }
 
   /**
@@ -224,19 +223,21 @@ export abstract class AbstractWorker<
     message: MessageValue<Data>
   ): void {
     try {
-      let taskPerformance = this.beginTaskPerformance(message)
+      let taskPerformance = this.beginTaskPerformance()
       const res = fn(message.data)
       taskPerformance = this.endTaskPerformance(taskPerformance)
       this.sendToMainWorker({
         data: res,
         taskPerformance,
+        workerId: this.id,
         id: message.id
       })
     } catch (e) {
-      const err = this.handleError(e as Error)
+      const errorMessage = this.handleError(e as Error | string)
       this.sendToMainWorker({
         taskError: {
-          message: err,
+          workerId: this.id,
+          message: errorMessage,
           data: message.data
         },
         id: message.id
@@ -256,22 +257,24 @@ export abstract class AbstractWorker<
     fn: WorkerAsyncFunction<Data, Response>,
     message: MessageValue<Data>
   ): void {
-    let taskPerformance = this.beginTaskPerformance(message)
+    let taskPerformance = this.beginTaskPerformance()
     fn(message.data)
       .then(res => {
         taskPerformance = this.endTaskPerformance(taskPerformance)
         this.sendToMainWorker({
           data: res,
           taskPerformance,
+          workerId: this.id,
           id: message.id
         })
         return null
       })
       .catch(e => {
-        const err = this.handleError(e as Error)
+        const errorMessage = this.handleError(e as Error | string)
         this.sendToMainWorker({
           taskError: {
-            message: err,
+            workerId: this.id,
+            message: errorMessage,
             data: message.data
           },
           id: message.id
@@ -297,13 +300,10 @@ export abstract class AbstractWorker<
     return fn
   }
 
-  private beginTaskPerformance (message: MessageValue<Data>): TaskPerformance {
-    const timestamp = performance.now()
+  private beginTaskPerformance (): TaskPerformance {
+    this.checkStatistics()
     return {
-      timestamp,
-      ...(this.statistics.waitTime && {
-        waitTime: timestamp - (message.timestamp ?? timestamp)
-      }),
+      timestamp: performance.now(),
       ...(this.statistics.elu && { elu: performance.eventLoopUtilization() })
     }
   }
@@ -311,6 +311,7 @@ export abstract class AbstractWorker<
   private endTaskPerformance (
     taskPerformance: TaskPerformance
   ): TaskPerformance {
+    this.checkStatistics()
     return {
       ...taskPerformance,
       ...(this.statistics.runTime && {
@@ -321,4 +322,10 @@ export abstract class AbstractWorker<
       })
     }
   }
+
+  private checkStatistics (): void {
+    if (this.statistics == null) {
+      throw new Error('Performance statistics computation requirements not set')
+    }
+  }
 }