Update src/worker/abstract-worker.ts

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

diff --git a/src/worker/abstract-worker.ts b/src/worker/abstract-worker.ts
index 4b68d8975a3cc21306a1d4ff19ab9592b5c48297..d57eacd70557a92befd1c132df8a199cab9aa68d 100644 (file)
--- a/src/worker/abstract-worker.ts
+++ b/src/worker/abstract-worker.ts
@@ -1,37 +1,72 @@
 import { AsyncResource } from 'async_hooks'
+import type { Worker } from 'cluster'
+import type { MessagePort } from 'worker_threads'
 import type { MessageValue } from '../utility-types'
 import type { WorkerOptions } from './worker-options'
+import { killBehaviorEnumeration } from './worker-options'
 
+const defaultMaxInactiveTime = 1000 * 60
+const defaultKillBehavior = killBehaviorEnumeration.SOFT
+
+/**
+ * Base class containing some shared logic for all poolifier workers.
+ *
+ * @template MainWorker Type of main worker.
+ * @template Data Type of data this worker receives from pool's execution.
+ * @template Response Type of response the worker sends back to the main worker.
+ */
 export abstract class AbstractWorker<
-  MainWorker,
+  MainWorker extends Worker | MessagePort,
   Data = unknown,
   Response = unknown
 > extends AsyncResource {
+  /**
+   * The maximum time to keep this worker alive while idle. The pool automatically checks and terminates this worker when the time expires.
+   */
   protected readonly maxInactiveTime: number
+  /**
+   * The kill behavior set as option on the Worker constructor or a default value.
+   */
+  protected readonly killBehavior: 'HARD' | 'SOFT'
+  /**
+   * Whether the worker is working asynchronously or not.
+   */
   protected readonly async: boolean
+  /**
+   * Timestamp of the last task processed by this worker.
+   */
   protected lastTask: number
+  /**
+   * Handler ID of the `interval` alive check.
+   */
   protected readonly interval?: NodeJS.Timeout
 
   /**
+   * Constructs a new poolifier worker.
    *
    * @param type The type of async event.
-   * @param isMain
-   * @param fn
-   * @param opts
+   * @param isMain Whether this is the main worker or not.
+   * @param fn Function processed by the worker when the pool's `execution` function is invoked.
+   * @param mainWorker Reference to main worker.
+   * @param opts Options for the worker.
    */
   public constructor (
     type: string,
     isMain: boolean,
     fn: (data: Data) => Response,
-    public readonly opts: WorkerOptions = {}
+    protected mainWorker?: MainWorker | null,
+    public readonly opts: WorkerOptions = {
+      killBehavior: defaultKillBehavior,
+      maxInactiveTime: defaultMaxInactiveTime
+    }
   ) {
     super(type)
-
-    this.maxInactiveTime = this.opts.maxInactiveTime ?? 1000 * 60
+    this.killBehavior = this.opts.killBehavior ?? defaultKillBehavior
+    this.maxInactiveTime = this.opts.maxInactiveTime ?? defaultMaxInactiveTime
     this.async = !!this.opts.async
     this.lastTask = Date.now()
-    if (!fn) throw new Error('Fn parameter is mandatory')
-    // keep the worker active
+    if (!fn) throw new Error('fn parameter is mandatory')
+    // Keep the worker active
     if (!isMain) {
       this.interval = setInterval(
         this.checkAlive.bind(this),
@@ -39,22 +74,71 @@ export abstract class AbstractWorker<
       )
       this.checkAlive.bind(this)()
     }
+
+    this.mainWorker?.on('message', (value: MessageValue<Data, MainWorker>) => {
+      if (value?.data && value.id) {
+        // Here you will receive messages
+        if (this.async) {
+          this.runInAsyncScope(this.runAsync.bind(this), this, fn, value)
+        } else {
+          this.runInAsyncScope(this.run.bind(this), this, fn, value)
+        }
+      } else if (value.parent) {
+        // Save a reference of the main worker to communicate with it
+        // This will be received once
+        this.mainWorker = value.parent
+      } else if (value.kill) {
+        // Here is time to kill this worker, just clearing the interval
+        if (this.interval) clearInterval(this.interval)
+        this.emitDestroy()
+      }
+    })
   }
 
-  protected abstract getMainWorker (): MainWorker
+  /**
+   * Returns the main worker.
+   *
+   * @returns Reference to the main worker.
+   */
+  protected getMainWorker (): MainWorker {
+    if (!this.mainWorker) {
+      throw new Error('Main worker was not set')
+    }
+    return this.mainWorker
+  }
 
+  /**
+   * Send a message to the main worker.
+   *
+   * @param message The response message.
+   */
   protected abstract sendToMainWorker (message: MessageValue<Response>): void
 
+  /**
+   * Check to see if the worker should be terminated, because its living too long.
+   */
   protected checkAlive (): void {
     if (Date.now() - this.lastTask > this.maxInactiveTime) {
-      this.sendToMainWorker({ kill: 1 })
+      this.sendToMainWorker({ kill: this.killBehavior })
     }
   }
 
+  /**
+   * Handle 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.
+   */
   protected handleError (e: Error | string): string {
     return (e as unknown) as string
   }
 
+  /**
+   * Run the given function synchronously.
+   *
+   * @param fn Function that will be executed.
+   * @param value Input data for the given function.
+   */
   protected run (
     fn: (data?: Data) => Response,
     value: MessageValue<Data>
@@ -70,6 +154,12 @@ export abstract class AbstractWorker<
     }
   }
 
+  /**
+   * Run the given function asynchronously.
+   *
+   * @param fn Function that will be executed.
+   * @param value Input data for the given function.
+   */
   protected runAsync (
     fn: (data?: Data) => Promise<Response>,
     value: MessageValue<Data>