Extract selection strategies to classes (#176)

[poolifier.git] / src / pools / thread / dynamic.ts

diff --git a/src/pools/thread/dynamic.ts b/src/pools/thread/dynamic.ts
index e80276d976640c25a9fe194847289e1ba0d7db45..fcf4b2ff4652b58b3050adbd46153d4b9ca2c10c 100644 (file)
--- a/src/pools/thread/dynamic.ts
+++ b/src/pools/thread/dynamic.ts
@@ -1,75 +1,42 @@
-import { EventEmitter } from 'events'
-import type { FixedThreadPoolOptions, WorkerWithMessageChannel } from './fixed'
+import type { PoolOptions } from '../abstract-pool'
+import type { ThreadWorkerWithMessageChannel } from './fixed'
 import { FixedThreadPool } from './fixed'
 
-class MyEmitter extends EventEmitter {}
-
-export type DynamicThreadPoolOptions = FixedThreadPoolOptions
-
 /**
- * A thread pool with a min/max number of threads, is possible to execute tasks in sync or async mode as you prefer.
+ * A thread pool with a dynamic number of threads, but a guaranteed minimum number of threads.
+ *
+ * This thread pool creates new threads when the others are busy, up to the maximum number of threads.
+ * When the maximum number of threads is reached, an event is emitted. If you want to listen to this event, use the pool's `emitter`.
  *
- * This thread pool will create new workers when the other ones are busy, until the max number of threads,
- * when the max number of threads is reached, an event will be emitted, if you want to listen this event use the emitter method.
+ * @template Data Type of data sent to the worker. This can only be serializable data.
+ * @template Response Type of response of execution. This can only be serializable data.
  *
  * @author [Alessandro Pio Ardizio](https://github.com/pioardi)
  * @since 0.0.1
  */
 export class DynamicThreadPool<
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  Data = any,
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  Response = any
+  Data = unknown,
+  Response = unknown
 > extends FixedThreadPool<Data, Response> {
-  public readonly emitter: MyEmitter
-
   /**
-   * @param min Min number of threads that will be always active
-   * @param max Max number of threads that will be active
-   * @param filename A file path with implementation of `ThreadWorker` class, relative path is fine.
-   * @param opts An object with possible options for example `errorHandler`, `onlineHandler`. Default: `{ maxTasks: 1000 }`
+   * Constructs a new poolifier dynamic thread pool.
+   *
+   * @param min Minimum number of threads which are always active.
+   * @param max Maximum number of threads that can be created by this pool.
+   * @param filePath Path to an implementation of a `ThreadWorker` file, which can be relative or absolute.
+   * @param opts Options for this dynamic thread pool. Default: `{ maxTasks: 1000 }`
    */
   public constructor (
-    public readonly min: number,
+    min: number,
     public readonly max: number,
-    public readonly filename: string,
-    public readonly opts: DynamicThreadPoolOptions = { maxTasks: 1000 }
+    filePath: string,
+    opts: PoolOptions<ThreadWorkerWithMessageChannel> = { maxTasks: 1000 }
   ) {
-    super(min, filename, opts)
-
-    this.emitter = new MyEmitter()
+    super(min, filePath, opts)
   }
 
-  protected chooseWorker (): WorkerWithMessageChannel {
-    let worker: WorkerWithMessageChannel | undefined
-    for (const entry of this.tasks) {
-      if (entry[1] === 0) {
-        worker = entry[0]
-        break
-      }
-    }
-
-    if (worker) {
-      // a worker is free, use it
-      return worker
-    } else {
-      if (this.workers.length === this.max) {
-        this.emitter.emit('FullPool')
-        return super.chooseWorker()
-      }
-      // all workers are busy create a new worker
-      const worker = this.newWorker()
-      worker.port2?.on('message', (message: { kill?: number }) => {
-        if (message.kill) {
-          worker.postMessage({ kill: 1 })
-          void worker.terminate()
-          // clean workers from data structures
-          const workerIndex = this.workers.indexOf(worker)
-          this.workers.splice(workerIndex, 1)
-          this.tasks.delete(worker)
-        }
-      })
-      return worker
-    }
+  /** @inheritdoc */
+  public isDynamic (): boolean {
+    return true
   }
 }