docs: enhance pool execute() method documentation

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

diff --git a/src/pools/pool.ts b/src/pools/pool.ts
index 8da89156ecef7869dd1d8a4e5fe5096a168e8280..907bfcb5982f8e1916877e516c3e791eddcc5be0 100644 (file)
--- a/src/pools/pool.ts
+++ b/src/pools/pool.ts
@@ -1,15 +1,70 @@
+import EventEmitter from 'node:events'
 import type {
   ErrorHandler,
   ExitHandler,
+  IWorker,
   MessageHandler,
-  OnlineHandler
-} from './pool-worker'
-import type { WorkerChoiceStrategy } from './selection-strategies/selection-strategies-types'
+  OnlineHandler,
+  WorkerNode
+} from './worker'
+import type {
+  WorkerChoiceStrategy,
+  WorkerChoiceStrategyOptions
+} from './selection-strategies/selection-strategies-types'
+
+/**
+ * Pool types.
+ *
+ * @enum
+ * @internal
+ */
+export enum PoolType {
+  /**
+   * Fixed pool type.
+   */
+  FIXED = 'fixed',
+  /**
+   * Dynamic pool type.
+   */
+  DYNAMIC = 'dynamic'
+}
+
+/**
+ * Pool events emitter.
+ */
+export class PoolEmitter extends EventEmitter {}
+
+/**
+ * Enumeration of pool events.
+ */
+export const PoolEvents = Object.freeze({
+  full: 'full',
+  busy: 'busy'
+} as const)
+
+/**
+ * Pool event.
+ */
+export type PoolEvent = keyof typeof PoolEvents
+
+/**
+ * Worker tasks queue options.
+ */
+export interface TasksQueueOptions {
+  /**
+   * Maximum number of tasks that can be executed concurrently on a worker.
+   *
+   * @defaultValue 1
+   */
+  concurrency?: number
+}
 
 /**
  * Options for a poolifier pool.
+ *
+ * @typeParam Worker - Type of worker.
  */
-export interface PoolOptions<Worker> {
+export interface PoolOptions<Worker extends IWorker> {
   /**
    * A function that will listen for message event on each worker.
    */
@@ -27,39 +82,115 @@ export interface PoolOptions<Worker> {
    */
   exitHandler?: ExitHandler<Worker>
   /**
-   * The work choice strategy to use in this pool.
+   * The worker choice strategy to use in this pool.
    */
   workerChoiceStrategy?: WorkerChoiceStrategy
+  /**
+   * The worker choice strategy options.
+   */
+  workerChoiceStrategyOptions?: WorkerChoiceStrategyOptions
   /**
    * Pool events emission.
    *
-   * @default true
+   * @defaultValue true
    */
   enableEvents?: boolean
+  /**
+   * Pool worker tasks queue.
+   *
+   * @defaultValue false
+   */
+  enableTasksQueue?: boolean
+  /**
+   * Pool worker tasks queue options.
+   */
+  tasksQueueOptions?: TasksQueueOptions
 }
 
 /**
  * Contract definition for a poolifier pool.
  *
- * @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.
+ * @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 execution response. This can only be serializable data.
  */
-export interface IPool<Data = unknown, Response = unknown> {
+export interface IPool<
+  Worker extends IWorker,
+  Data = unknown,
+  Response = unknown
+> {
+  /**
+   * Pool type.
+   *
+   * If it is `'dynamic'`, it provides the `max` property.
+   */
+  readonly type: PoolType
+  /**
+   * Pool worker nodes.
+   */
+  readonly workerNodes: Array<WorkerNode<Worker, Data>>
+  /**
+   * Emitter on which events can be listened to.
+   *
+   * Events that can currently be listened to:
+   *
+   * - `'full'`: Emitted when the pool is dynamic and full.
+   * - `'busy'`: Emitted when the pool is busy.
+   */
+  readonly emitter?: PoolEmitter
   /**
-   * Perform the task specified in the constructor with the data parameter.
+   * Finds a free worker node key based on the number of tasks the worker has applied.
    *
-   * @param data The input for the specified task. This can only be serializable data.
+   * If a worker is found with `0` running tasks, it is detected as free and its worker node key is returned.
+   *
+   * If no free worker is found, `-1` is returned.
+   *
+   * @returns A worker node key if there is one, `-1` otherwise.
+   */
+  findFreeWorkerNodeKey: () => number
+  /**
+   * Executes the function specified in the constructor with the task data input parameter.
+   *
+   * @param data - The task input data for the specified function. This can only be serializable data.
    * @returns Promise that will be resolved when the task is successfully completed.
    */
-  execute(data: Data): Promise<Response>
+  execute: (data: Data) => Promise<Response>
+  /**
+   * Shutdowns every current worker in this pool.
+   */
+  destroy: () => Promise<void>
   /**
-   * Shut down every current worker in this pool.
+   * Sets the worker choice strategy in this pool.
+   *
+   * @param workerChoiceStrategy - The worker choice strategy.
+   * @param workerChoiceStrategyOptions - The worker choice strategy options.
+   */
+  setWorkerChoiceStrategy: (
+    workerChoiceStrategy: WorkerChoiceStrategy,
+    workerChoiceStrategyOptions?: WorkerChoiceStrategyOptions
+  ) => void
+  /**
+   * Sets the worker choice strategy options in this pool.
+   *
+   * @param workerChoiceStrategyOptions - The worker choice strategy options.
+   */
+  setWorkerChoiceStrategyOptions: (
+    workerChoiceStrategyOptions: WorkerChoiceStrategyOptions
+  ) => void
+  /**
+   * Enables/disables the worker tasks queue in this pool.
+   *
+   * @param enable - Whether to enable or disable the worker tasks queue.
+   * @param tasksQueueOptions - The worker tasks queue options.
    */
-  destroy(): Promise<void>
+  enableTasksQueue: (
+    enable: boolean,
+    tasksQueueOptions?: TasksQueueOptions
+  ) => void
   /**
-   * Set the worker choice strategy in this pool.
+   * Sets the worker tasks queue options in this pool.
    *
-   * @param workerChoiceStrategy The worker choice strategy.
+   * @param tasksQueueOptions - The worker tasks queue options.
    */
-  setWorkerChoiceStrategy(workerChoiceStrategy: WorkerChoiceStrategy): void
+  setTasksQueueOptions: (tasksQueueOptions: TasksQueueOptions) => void
 }