fix: properly account worker choice retries for WRR

[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 a3e3379c9ac461fc7cd16c2d32bb8735ca2d50ff..9a015347bc2a430172855116224da8cfc89f2800 100644 (file)
--- a/src/pools/selection-strategies/worker-choice-strategy-context.ts
+++ b/src/pools/selection-strategies/worker-choice-strategy-context.ts
@@ -1,4 +1,4 @@
-import { DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS } from '../../utils'
+import { buildInternalWorkerChoiceStrategyOptions } from '../../utils'
 import type { IPool } from '../pool'
 import type { IWorker } from '../worker'
 import { FairShareWorkerChoiceStrategy } from './fair-share-worker-choice-strategy'
@@ -9,10 +9,10 @@ import { LeastEluWorkerChoiceStrategy } from './least-elu-worker-choice-strategy
 import { RoundRobinWorkerChoiceStrategy } from './round-robin-worker-choice-strategy'
 import type {
   IWorkerChoiceStrategy,
+  InternalWorkerChoiceStrategyOptions,
   StrategyPolicy,
   TaskStatisticsRequirements,
-  WorkerChoiceStrategy,
-  WorkerChoiceStrategyOptions
+  WorkerChoiceStrategy
 } from './selection-strategies-types'
 import { WorkerChoiceStrategies } from './selection-strategies-types'
 import { WeightedRoundRobinWorkerChoiceStrategy } from './weighted-round-robin-worker-choice-strategy'
@@ -34,11 +34,6 @@ export class WorkerChoiceStrategyContext<
   IWorkerChoiceStrategy
   >
 
-  /**
-   * The number of times the worker choice strategy in the context has been retried.
-   */
-  private choiceRetriesCount = 0
-
   /**
    * Worker choice strategy context constructor.
    *
@@ -49,9 +44,12 @@ export class WorkerChoiceStrategyContext<
   public constructor (
     pool: IPool<Worker, Data, Response>,
     private workerChoiceStrategy: WorkerChoiceStrategy = WorkerChoiceStrategies.ROUND_ROBIN,
-    private opts: WorkerChoiceStrategyOptions = DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS
+    private opts?: InternalWorkerChoiceStrategyOptions
   ) {
-    this.opts = { ...DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS, ...opts }
+    this.opts = buildInternalWorkerChoiceStrategyOptions(
+      pool.info.maxSize,
+      this.opts
+    )
     this.execute = this.execute.bind(this)
     this.workerChoiceStrategies = new Map<
     WorkerChoiceStrategy,
@@ -61,35 +59,35 @@ export class WorkerChoiceStrategyContext<
         WorkerChoiceStrategies.ROUND_ROBIN,
         new (RoundRobinWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
           pool,
-          opts
+          this.opts
         )
       ],
       [
         WorkerChoiceStrategies.LEAST_USED,
         new (LeastUsedWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
           pool,
-          opts
+          this.opts
         )
       ],
       [
         WorkerChoiceStrategies.LEAST_BUSY,
         new (LeastBusyWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
           pool,
-          opts
+          this.opts
         )
       ],
       [
         WorkerChoiceStrategies.LEAST_ELU,
         new (LeastEluWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
           pool,
-          opts
+          this.opts
         )
       ],
       [
         WorkerChoiceStrategies.FAIR_SHARE,
         new (FairShareWorkerChoiceStrategy.bind(this))<Worker, Data, Response>(
           pool,
-          opts
+          this.opts
         )
       ],
       [
@@ -98,7 +96,7 @@ export class WorkerChoiceStrategyContext<
         Worker,
         Data,
         Response
-        >(pool, opts)
+        >(pool, this.opts)
       ],
       [
         WorkerChoiceStrategies.INTERLEAVED_WEIGHTED_ROUND_ROBIN,
@@ -106,7 +104,7 @@ export class WorkerChoiceStrategyContext<
         Worker,
         Data,
         Response
-        >(pool, opts)
+        >(pool, this.opts)
       ]
     ])
   }
@@ -168,26 +166,44 @@ export class WorkerChoiceStrategyContext<
    * Executes the worker choice strategy in the context algorithm.
    *
    * @returns The key of the worker node.
-   * @throws {@link https://nodejs.org/api/errors.html#class-error} If the worker node key is null or undefined.
+   * @throws {@link https://nodejs.org/api/errors.html#class-error} If after configured retries the worker node key is null or undefined.
    */
   public execute (): number {
-    const workerNodeKey = (
-      this.workerChoiceStrategies.get(
-        this.workerChoiceStrategy
-      ) as IWorkerChoiceStrategy
-    ).choose()
-    if (
-      workerNodeKey == null &&
-      this.choiceRetriesCount < (this.opts.choiceRetries as number)
-    ) {
-      this.choiceRetriesCount++
+    const workerChoiceStrategy = this.workerChoiceStrategies.get(
+      this.workerChoiceStrategy
+    ) as IWorkerChoiceStrategy
+    if (!workerChoiceStrategy.hasPoolWorkerNodesReady()) {
       return this.execute()
-    } else if (workerNodeKey == null) {
-      throw new TypeError(
-        `Worker node key chosen is null or undefined after ${this.choiceRetriesCount} retries`
+    }
+    return this.executeStrategy(workerChoiceStrategy)
+  }
+
+  /**
+   * Executes the given worker choice strategy.
+   *
+   * @param workerChoiceStrategy - The worker choice strategy.
+   * @returns The key of the worker node.
+   * @throws {@link https://nodejs.org/api/errors.html#class-error} If after configured retries the worker node key is null or undefined.
+   */
+  private executeStrategy (workerChoiceStrategy: IWorkerChoiceStrategy): number {
+    let workerNodeKey: number | undefined
+    let chooseCount = 0
+    let retriesCount = 0
+    do {
+      workerNodeKey = workerChoiceStrategy.choose()
+      if (workerNodeKey == null && chooseCount > 0) {
+        retriesCount++
+      }
+      chooseCount++
+    } while (
+      workerNodeKey == null &&
+      retriesCount < (this.opts?.retries as number)
+    )
+    if (workerNodeKey == null) {
+      throw new Error(
+        `Worker node key chosen is null or undefined after ${retriesCount} retries`
       )
     }
-    this.choiceRetriesCount = 0
     return workerNodeKey
   }
 
@@ -208,12 +224,19 @@ export class WorkerChoiceStrategyContext<
   /**
    * Sets the worker choice strategies in the context options.
    *
+   * @param pool - The pool instance.
    * @param opts - The worker choice strategy options.
    */
-  public setOptions (opts: WorkerChoiceStrategyOptions): void {
-    this.opts = { ...DEFAULT_WORKER_CHOICE_STRATEGY_OPTIONS, ...opts }
+  public setOptions (
+    pool: IPool<Worker, Data, Response>,
+    opts?: InternalWorkerChoiceStrategyOptions
+  ): void {
+    this.opts = buildInternalWorkerChoiceStrategyOptions(
+      pool.info.maxSize,
+      opts
+    )
     for (const workerChoiceStrategy of this.workerChoiceStrategies.values()) {
-      workerChoiceStrategy.setOptions(opts)
+      workerChoiceStrategy.setOptions(this.opts)
     }
   }
 }