refactor: apply stricter strategy design pattern requirements on worker

[poolifier.git] / src / pools / selection-strategies / worker-choice-strategy-context.ts

diff --git a/src/pools/selection-strategies/worker-choice-strategy-context.ts b/src/pools/selection-strategies/worker-choice-strategy-context.ts
index 836a1cb5052c5f2219e9e872b3a979684b0336af..41b515b816d00dc991c27d8143efe80ec7c6116a 100644 (file)
--- a/src/pools/selection-strategies/worker-choice-strategy-context.ts
+++ b/src/pools/selection-strategies/worker-choice-strategy-context.ts
@@ -1,94 +1,94 @@
 import type { IPoolInternal } from '../pool-internal'
-import { PoolType } from '../pool-internal'
 import type { IPoolWorker } from '../pool-worker'
-import { DynamicPoolWorkerChoiceStrategy } from './dynamic-pool-worker-choice-strategy'
 import type {
   IWorkerChoiceStrategy,
+  RequiredStatistics,
   WorkerChoiceStrategy
 } from './selection-strategies-types'
 import { WorkerChoiceStrategies } from './selection-strategies-types'
-import { SelectionStrategiesUtils } from './selection-strategies-utils'
+import { getWorkerChoiceStrategy } from './selection-strategies-utils'
 
 /**
  * The worker choice strategy context.
  *
- * @template Worker Type of worker.
- * @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.
+ * @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.
  */
 export class WorkerChoiceStrategyContext<
   Worker extends IPoolWorker,
   Data,
   Response
 > {
-  private workerChoiceStrategy!: IWorkerChoiceStrategy<Worker>
+  private workerChoiceStrategy: IWorkerChoiceStrategy<Worker, Data, Response>
 
   /**
    * Worker choice strategy context constructor.
    *
-   * @param pool The pool instance.
-   * @param createDynamicallyWorkerCallback The worker creation callback for dynamic pool.
-   * @param workerChoiceStrategy The worker choice strategy.
+   * @param pool - The pool instance.
+   * @param createWorkerCallback - The worker creation callback for dynamic pool.
+   * @param workerChoiceStrategy - The worker choice strategy.
    */
   public constructor (
-    private readonly pool: IPoolInternal<Worker, Data, Response>,
-    private createDynamicallyWorkerCallback: () => Worker,
+    pool: IPoolInternal<Worker, Data, Response>,
+    private readonly createWorkerCallback: () => number,
     workerChoiceStrategy: WorkerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN
   ) {
-    this.setWorkerChoiceStrategy(workerChoiceStrategy)
-  }
-
-  /**
-   * Gets the worker choice strategy instance specific to the pool type.
-   *
-   * @param workerChoiceStrategy The worker choice strategy.
-   * @returns The worker choice strategy instance for the pool type.
-   */
-  private getPoolWorkerChoiceStrategy (
-    workerChoiceStrategy: WorkerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN
-  ): IWorkerChoiceStrategy<Worker> {
-    if (this.pool.type === PoolType.DYNAMIC) {
-      return new DynamicPoolWorkerChoiceStrategy(
-        this.pool,
-        this.createDynamicallyWorkerCallback,
-        workerChoiceStrategy
-      )
-    }
-    return SelectionStrategiesUtils.getWorkerChoiceStrategy(
-      this.pool,
+    this.execute.bind(this)
+    this.workerChoiceStrategy = getWorkerChoiceStrategy<Worker, Data, Response>(
+      pool,
       workerChoiceStrategy
     )
   }
 
   /**
-   * Gets the worker choice strategy used in the context.
+   * Gets the worker choice strategy required statistics.
    *
-   * @returns The worker choice strategy.
+   * @returns The required statistics.
    */
-  public getWorkerChoiceStrategy (): IWorkerChoiceStrategy<Worker> {
-    return this.workerChoiceStrategy
+  public getRequiredStatistics (): RequiredStatistics {
+    return this.workerChoiceStrategy.requiredStatistics
   }
 
   /**
    * Sets the worker choice strategy to use in the context.
    *
-   * @param workerChoiceStrategy The worker choice strategy to set.
+   * @param workerChoiceStrategy - The worker choice strategy to set.
    */
   public setWorkerChoiceStrategy (
+    pool: IPoolInternal<Worker, Data, Response>,
     workerChoiceStrategy: WorkerChoiceStrategy
   ): void {
     this.workerChoiceStrategy?.reset()
-    this.workerChoiceStrategy = this.getPoolWorkerChoiceStrategy(
+    this.workerChoiceStrategy = getWorkerChoiceStrategy<Worker, Data, Response>(
+      pool,
       workerChoiceStrategy
     )
   }
 
   /**
-   * Chooses a worker with the underlying selection strategy.
+   * Chooses a worker with the worker choice strategy.
    *
-   * @returns The chosen one.
+   * @returns The key of the chosen one.
    */
-  public execute (): Worker {
+  public execute (): number {
+    if (
+      this.workerChoiceStrategy.isDynamicPool &&
+      !this.workerChoiceStrategy.pool.full &&
+      this.workerChoiceStrategy.pool.findFreeWorkerKey() === -1
+    ) {
+      return this.createWorkerCallback()
+    }
     return this.workerChoiceStrategy.choose()
   }
+
+  /**
+   * Removes a worker in the worker choice strategy internals.
+   *
+   * @param workerKey - The key of the worker to remove.
+   * @returns `true` if the removal is successful, `false` otherwise.
+   */
+  public remove (workerKey: number): boolean {
+    return this.workerChoiceStrategy.remove(workerKey)
+  }
 }