refactor: cleanup queue API
[poolifier.git] / src / pools / abstract-pool.ts
index 1668813354538bfcf5d8a39c38007c5d0f42755d..06cdc3cd5d635c1e13b209228631bea7e6960fd6 100644 (file)
@@ -1,31 +1,41 @@
 import crypto from 'node:crypto'
 import type { MessageValue, PromiseResponseWrapper } from '../utility-types'
-import { EMPTY_FUNCTION, median } from '../utils'
+import {
+  DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS,
+  EMPTY_FUNCTION,
+  median
+} from '../utils'
 import { KillBehaviors, isKillBehavior } from '../worker/worker-options'
-import { PoolEvents, type PoolOptions } from './pool'
-import { PoolEmitter } from './pool'
-import type { IPoolInternal } from './pool-internal'
-import { PoolType } from './pool-internal'
+import { CircularArray } from '../circular-array'
+import { Queue } from '../queue'
+import {
+  type IPool,
+  PoolEmitter,
+  PoolEvents,
+  type PoolOptions,
+  PoolType,
+  type TasksQueueOptions
+} from './pool'
 import type { IWorker, Task, TasksUsage, WorkerNode } from './worker'
 import {
   WorkerChoiceStrategies,
-  type WorkerChoiceStrategy
+  type WorkerChoiceStrategy,
+  type WorkerChoiceStrategyOptions
 } from './selection-strategies/selection-strategies-types'
 import { WorkerChoiceStrategyContext } from './selection-strategies/worker-choice-strategy-context'
-import { CircularArray } from '../circular-array'
 
 /**
  * Base class that implements some shared logic for all poolifier pools.
  *
  * @typeParam Worker - Type of worker which manages this pool.
  * @typeParam Data - Type of data sent to the worker. This can only be serializable data.
- * @typeParam Response - Type of response of execution. This can only be serializable data.
+ * @typeParam Response - Type of execution response. This can only be serializable data.
  */
 export abstract class AbstractPool<
   Worker extends IWorker,
   Data = unknown,
   Response = unknown
-> implements IPoolInternal<Worker, Data, Response> {
+> implements IPool<Worker, Data, Response> {
   /** @inheritDoc */
   public readonly workerNodes: Array<WorkerNode<Worker, Data>> = []
 
@@ -33,12 +43,12 @@ export abstract class AbstractPool<
   public readonly emitter?: PoolEmitter
 
   /**
-   * The promise response map.
+   * The execution response promise map.
    *
    * - `key`: The message id of each submitted task.
-   * - `value`: An object that contains the worker, the promise resolve and reject callbacks.
+   * - `value`: An object that contains the worker, the execution response promise resolve and reject callbacks.
    *
-   * When we receive a message from the worker we get a map entry with the promise resolve/reject bound to the message.
+   * When we receive a message from the worker, we get a map entry with the promise resolve/reject bound to the message id.
    */
   protected promiseResponseMap: Map<
   string,
@@ -60,7 +70,7 @@ export abstract class AbstractPool<
    * Constructs a new poolifier pool.
    *
    * @param numberOfWorkers - Number of workers that this pool should manage.
-   * @param filePath - Path to the worker-file.
+   * @param filePath - Path to the worker file.
    * @param opts - Options for the pool.
    */
   public constructor (
@@ -75,10 +85,10 @@ export abstract class AbstractPool<
     this.checkFilePath(this.filePath)
     this.checkPoolOptions(this.opts)
 
-    this.chooseWorkerNode.bind(this)
-    this.internalExecute.bind(this)
-    this.checkAndEmitEvents.bind(this)
-    this.sendToWorker.bind(this)
+    this.chooseWorkerNode = this.chooseWorkerNode.bind(this)
+    this.executeTask = this.executeTask.bind(this)
+    this.enqueueTask = this.enqueueTask.bind(this)
+    this.checkAndEmitEvents = this.checkAndEmitEvents.bind(this)
 
     this.setupHook()
 
@@ -93,7 +103,11 @@ export abstract class AbstractPool<
     Worker,
     Data,
     Response
-    >(this, this.opts.workerChoiceStrategy)
+    >(
+      this,
+      this.opts.workerChoiceStrategy,
+      this.opts.workerChoiceStrategyOptions
+    )
   }
 
   private checkFilePath (filePath: string): void {
@@ -127,8 +141,18 @@ export abstract class AbstractPool<
     this.opts.workerChoiceStrategy =
       opts.workerChoiceStrategy ?? WorkerChoiceStrategies.ROUND_ROBIN
     this.checkValidWorkerChoiceStrategy(this.opts.workerChoiceStrategy)
+    this.opts.workerChoiceStrategyOptions =
+      opts.workerChoiceStrategyOptions ?? DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
     this.opts.enableEvents = opts.enableEvents ?? true
     this.opts.enableTasksQueue = opts.enableTasksQueue ?? false
+    if (this.opts.enableTasksQueue) {
+      this.checkValidTasksQueueOptions(
+        opts.tasksQueueOptions as TasksQueueOptions
+      )
+      this.opts.tasksQueueOptions = this.buildTasksQueueOptions(
+        opts.tasksQueueOptions as TasksQueueOptions
+      )
+    }
   }
 
   private checkValidWorkerChoiceStrategy (
@@ -141,6 +165,18 @@ export abstract class AbstractPool<
     }
   }
 
+  private checkValidTasksQueueOptions (
+    tasksQueueOptions: TasksQueueOptions
+  ): void {
+    if ((tasksQueueOptions?.concurrency as number) <= 0) {
+      throw new Error(
+        `Invalid worker tasks concurrency '${
+          tasksQueueOptions.concurrency as number
+        }'`
+      )
+    }
+  }
+
   /** @inheritDoc */
   public abstract get type (): PoolType
 
@@ -162,7 +198,7 @@ export abstract class AbstractPool<
       return 0
     }
     return this.workerNodes.reduce(
-      (accumulator, workerNode) => accumulator + workerNode.tasksQueue.length,
+      (accumulator, workerNode) => accumulator + workerNode.tasksQueue.size,
       0
     )
   }
@@ -181,69 +217,119 @@ export abstract class AbstractPool<
 
   /** @inheritDoc */
   public setWorkerChoiceStrategy (
-    workerChoiceStrategy: WorkerChoiceStrategy
+    workerChoiceStrategy: WorkerChoiceStrategy,
+    workerChoiceStrategyOptions?: WorkerChoiceStrategyOptions
   ): void {
     this.checkValidWorkerChoiceStrategy(workerChoiceStrategy)
     this.opts.workerChoiceStrategy = workerChoiceStrategy
-    for (const [index, workerNode] of this.workerNodes.entries()) {
-      this.setWorkerNode(
-        index,
-        workerNode.worker,
-        {
-          run: 0,
-          running: 0,
-          runTime: 0,
-          runTimeHistory: new CircularArray(),
-          avgRunTime: 0,
-          medRunTime: 0,
-          error: 0
-        },
-        workerNode.tasksQueue
-      )
+    for (const workerNode of this.workerNodes) {
+      this.setWorkerNodeTasksUsage(workerNode, {
+        run: 0,
+        running: 0,
+        runTime: 0,
+        runTimeHistory: new CircularArray(),
+        avgRunTime: 0,
+        medRunTime: 0,
+        error: 0
+      })
     }
     this.workerChoiceStrategyContext.setWorkerChoiceStrategy(
-      workerChoiceStrategy
+      this.opts.workerChoiceStrategy
+    )
+    if (workerChoiceStrategyOptions != null) {
+      this.setWorkerChoiceStrategyOptions(workerChoiceStrategyOptions)
+    }
+  }
+
+  /** @inheritDoc */
+  public setWorkerChoiceStrategyOptions (
+    workerChoiceStrategyOptions: WorkerChoiceStrategyOptions
+  ): void {
+    this.opts.workerChoiceStrategyOptions = workerChoiceStrategyOptions
+    this.workerChoiceStrategyContext.setOptions(
+      this.opts.workerChoiceStrategyOptions
     )
   }
 
   /** @inheritDoc */
-  public abstract get full (): boolean
+  public enableTasksQueue (
+    enable: boolean,
+    tasksQueueOptions?: TasksQueueOptions
+  ): void {
+    if (this.opts.enableTasksQueue === true && !enable) {
+      this.flushTasksQueues()
+    }
+    this.opts.enableTasksQueue = enable
+    this.setTasksQueueOptions(tasksQueueOptions as TasksQueueOptions)
+  }
 
   /** @inheritDoc */
-  public abstract get busy (): boolean
+  public setTasksQueueOptions (tasksQueueOptions: TasksQueueOptions): void {
+    if (this.opts.enableTasksQueue === true) {
+      this.checkValidTasksQueueOptions(tasksQueueOptions)
+      this.opts.tasksQueueOptions =
+        this.buildTasksQueueOptions(tasksQueueOptions)
+    } else {
+      delete this.opts.tasksQueueOptions
+    }
+  }
+
+  private buildTasksQueueOptions (
+    tasksQueueOptions: TasksQueueOptions
+  ): TasksQueueOptions {
+    return {
+      concurrency: tasksQueueOptions?.concurrency ?? 1
+    }
+  }
+
+  /**
+   * Whether the pool is full or not.
+   *
+   * The pool filling boolean status.
+   */
+  protected abstract get full (): boolean
+
+  /**
+   * Whether the pool is busy or not.
+   *
+   * The pool busyness boolean status.
+   */
+  protected abstract get busy (): boolean
 
   protected internalBusy (): boolean {
     return (
-      this.numberOfRunningTasks >= this.numberOfWorkers &&
-      this.findFreeWorkerNodeKey() === -1
+      this.workerNodes.findIndex(workerNode => {
+        return workerNode.tasksUsage?.running === 0
+      }) === -1
     )
   }
 
   /** @inheritDoc */
-  public findFreeWorkerNodeKey (): number {
-    return this.workerNodes.findIndex(workerNode => {
-      return workerNode.tasksUsage?.running === 0
-    })
-  }
-
-  /** @inheritDoc */
-  public async execute (data: Data): Promise<Response> {
+  public async execute (data?: Data): Promise<Response> {
     const [workerNodeKey, workerNode] = this.chooseWorkerNode()
     const submittedTask: Task<Data> = {
       // eslint-disable-next-line @typescript-eslint/consistent-type-assertions
       data: data ?? ({} as Data),
       id: crypto.randomUUID()
     }
-    const res = this.internalExecute(workerNodeKey, workerNode, submittedTask)
-    let currentTask: Task<Data> = submittedTask
+    const res = new Promise<Response>((resolve, reject) => {
+      this.promiseResponseMap.set(submittedTask.id as string, {
+        resolve,
+        reject,
+        worker: workerNode.worker
+      })
+    })
     if (
       this.opts.enableTasksQueue === true &&
-      (this.busy || this.tasksQueueLength(workerNodeKey) > 0)
+      (this.busy ||
+        this.workerNodes[workerNodeKey].tasksUsage.running >=
+          ((this.opts.tasksQueueOptions as TasksQueueOptions)
+            .concurrency as number))
     ) {
       this.enqueueTask(workerNodeKey, submittedTask)
-      currentTask = this.dequeueTask(workerNodeKey) as Task<Data>
+    } else {
+      this.executeTask(workerNodeKey, submittedTask)
     }
-    this.sendToWorker(workerNode.worker, currentTask)
     this.checkAndEmitEvents()
     // eslint-disable-next-line @typescript-eslint/return-await
     return res
@@ -252,8 +338,8 @@ export abstract class AbstractPool<
   /** @inheritDoc */
   public async destroy (): Promise<void> {
     await Promise.all(
-      this.workerNodes.map(async workerNode => {
-        this.flushTasksQueueByWorker(workerNode.worker)
+      this.workerNodes.map(async (workerNode, workerNodeKey) => {
+        this.flushTasksQueue(workerNodeKey)
         await this.destroyWorker(workerNode.worker)
       })
     )
@@ -267,7 +353,7 @@ export abstract class AbstractPool<
   protected abstract destroyWorker (worker: Worker): void | Promise<void>
 
   /**
-   * Setup hook to run code before worker node are created in the abstract constructor.
+   * Setup hook to execute code before worker node are created in the abstract constructor.
    * Can be overridden
    *
    * @virtual
@@ -282,27 +368,27 @@ export abstract class AbstractPool<
   protected abstract isMain (): boolean
 
   /**
-   * Hook executed before the worker task promise resolution.
+   * Hook executed before the worker task execution.
    * Can be overridden.
    *
    * @param workerNodeKey - The worker node key.
    */
-  protected beforePromiseResponseHook (workerNodeKey: number): void {
+  protected beforeTaskExecutionHook (workerNodeKey: number): void {
     ++this.workerNodes[workerNodeKey].tasksUsage.running
   }
 
   /**
-   * Hook executed after the worker task promise resolution.
+   * Hook executed after the worker task execution.
    * Can be overridden.
    *
    * @param worker - The worker.
    * @param message - The received message.
    */
-  protected afterPromiseResponseHook (
+  protected afterTaskExecutionHook (
     worker: Worker,
     message: MessageValue<Response>
   ): void {
-    const workerTasksUsage = this.getWorkerTasksUsage(worker) as TasksUsage
+    const workerTasksUsage = this.getWorkerTasksUsage(worker)
     --workerTasksUsage.running
     ++workerTasksUsage.run
     if (message.error != null) {
@@ -333,11 +419,7 @@ export abstract class AbstractPool<
    */
   protected chooseWorkerNode (): [number, WorkerNode<Worker, Data>] {
     let workerNodeKey: number
-    if (
-      this.type === PoolType.DYNAMIC &&
-      !this.full &&
-      this.findFreeWorkerNodeKey() === -1
-    ) {
+    if (this.type === PoolType.DYNAMIC && !this.full && this.internalBusy()) {
       const workerCreated = this.createAndSetupWorker()
       this.registerWorkerMessageListener(workerCreated, message => {
         if (
@@ -347,7 +429,7 @@ export abstract class AbstractPool<
         ) {
           // Kill message received from the worker: no new tasks are submitted to that worker for a while ( > maxInactiveTime)
           this.flushTasksQueueByWorker(workerCreated)
-          void this.destroyWorker(workerCreated)
+          void (this.destroyWorker(workerCreated) as Promise<void>)
         }
       })
       workerNodeKey = this.getWorkerNodeKey(workerCreated)
@@ -423,7 +505,7 @@ export abstract class AbstractPool<
   protected workerListener (): (message: MessageValue<Response>) => void {
     return message => {
       if (message.id != null) {
-        // Task response received
+        // Task execution response received
         const promiseResponse = this.promiseResponseMap.get(message.id)
         if (promiseResponse != null) {
           if (message.error != null) {
@@ -431,15 +513,15 @@ export abstract class AbstractPool<
           } else {
             promiseResponse.resolve(message.data as Response)
           }
-          this.afterPromiseResponseHook(promiseResponse.worker, message)
+          this.afterTaskExecutionHook(promiseResponse.worker, message)
           this.promiseResponseMap.delete(message.id)
           const workerNodeKey = this.getWorkerNodeKey(promiseResponse.worker)
           if (
             this.opts.enableTasksQueue === true &&
-            this.tasksQueueLength(workerNodeKey) > 0
+            this.tasksQueueSize(workerNodeKey) > 0
           ) {
-            this.sendToWorker(
-              promiseResponse.worker,
+            this.executeTask(
+              workerNodeKey,
               this.dequeueTask(workerNodeKey) as Task<Data>
             )
           }
@@ -448,21 +530,6 @@ export abstract class AbstractPool<
     }
   }
 
-  private async internalExecute (
-    workerNodeKey: number,
-    workerNode: WorkerNode<Worker, Data>,
-    task: Task<Data>
-  ): Promise<Response> {
-    this.beforePromiseResponseHook(workerNodeKey)
-    return await new Promise<Response>((resolve, reject) => {
-      this.promiseResponseMap.set(task.id, {
-        resolve,
-        reject,
-        worker: workerNode.worker
-      })
-    })
-  }
-
   private checkAndEmitEvents (): void {
     if (this.opts.enableEvents === true) {
       if (this.busy) {
@@ -474,13 +541,27 @@ export abstract class AbstractPool<
     }
   }
 
+  /**
+   * Sets the given worker node its tasks usage in the pool.
+   *
+   * @param workerNode - The worker node.
+   * @param tasksUsage - The worker node tasks usage.
+   */
+  private setWorkerNodeTasksUsage (
+    workerNode: WorkerNode<Worker, Data>,
+    tasksUsage: TasksUsage
+  ): void {
+    workerNode.tasksUsage = tasksUsage
+  }
+
   /**
    * Gets the given worker its tasks usage in the pool.
    *
    * @param worker - The worker.
+   * @throws Error if the worker is not found in the pool worker nodes.
    * @returns The worker tasks usage.
    */
-  private getWorkerTasksUsage (worker: Worker): TasksUsage | undefined {
+  private getWorkerTasksUsage (worker: Worker): TasksUsage {
     const workerNodeKey = this.getWorkerNodeKey(worker)
     if (workerNodeKey !== -1) {
       return this.workerNodes[workerNodeKey].tasksUsage
@@ -506,7 +587,7 @@ export abstract class AbstractPool<
         medRunTime: 0,
         error: 0
       },
-      tasksQueue: []
+      tasksQueue: new Queue<Task<Data>>()
     })
   }
 
@@ -522,7 +603,7 @@ export abstract class AbstractPool<
     workerNodeKey: number,
     worker: Worker,
     tasksUsage: TasksUsage,
-    tasksQueue: Array<Task<Data>>
+    tasksQueue: Queue<Task<Data>>
   ): void {
     this.workerNodes[workerNodeKey] = {
       worker,
@@ -536,35 +617,48 @@ export abstract class AbstractPool<
    *
    * @param worker - The worker.
    */
-  protected removeWorkerNode (worker: Worker): void {
+  private removeWorkerNode (worker: Worker): void {
     const workerNodeKey = this.getWorkerNodeKey(worker)
     this.workerNodes.splice(workerNodeKey, 1)
     this.workerChoiceStrategyContext.remove(workerNodeKey)
   }
 
-  protected enqueueTask (workerNodeKey: number, task: Task<Data>): void {
-    this.workerNodes[workerNodeKey].tasksQueue.push(task)
+  private executeTask (workerNodeKey: number, task: Task<Data>): void {
+    this.beforeTaskExecutionHook(workerNodeKey)
+    this.sendToWorker(this.workerNodes[workerNodeKey].worker, task)
   }
 
-  protected dequeueTask (workerNodeKey: number): Task<Data> | undefined {
-    return this.workerNodes[workerNodeKey].tasksQueue.shift()
+  private enqueueTask (workerNodeKey: number, task: Task<Data>): number {
+    return this.workerNodes[workerNodeKey].tasksQueue.enqueue(task)
   }
 
-  protected tasksQueueLength (workerNodeKey: number): number {
-    return this.workerNodes[workerNodeKey].tasksQueue.length
+  private dequeueTask (workerNodeKey: number): Task<Data> | undefined {
+    return this.workerNodes[workerNodeKey].tasksQueue.dequeue()
   }
 
-  protected flushTasksQueue (workerNodeKey: number): void {
-    if (this.tasksQueueLength(workerNodeKey) > 0) {
-      for (const task of this.workerNodes[workerNodeKey].tasksQueue) {
-        this.sendToWorker(this.workerNodes[workerNodeKey].worker, task)
+  private tasksQueueSize (workerNodeKey: number): number {
+    return this.workerNodes[workerNodeKey].tasksQueue.size
+  }
+
+  private flushTasksQueue (workerNodeKey: number): void {
+    if (this.tasksQueueSize(workerNodeKey) > 0) {
+      for (let i = 0; i < this.tasksQueueSize(workerNodeKey); i++) {
+        this.executeTask(
+          workerNodeKey,
+          this.dequeueTask(workerNodeKey) as Task<Data>
+        )
       }
-      this.workerNodes[workerNodeKey].tasksQueue = []
     }
   }
 
-  protected flushTasksQueueByWorker (worker: Worker): void {
+  private flushTasksQueueByWorker (worker: Worker): void {
     const workerNodeKey = this.getWorkerNodeKey(worker)
     this.flushTasksQueue(workerNodeKey)
   }
+
+  private flushTasksQueues (): void {
+    for (const [workerNodeKey] of this.workerNodes.entries()) {
+      this.flushTasksQueue(workerNodeKey)
+    }
+  }
 }