1 // Partial Copyright Jerome Benoit. 2021-2024. All Rights Reserved.
3 import { EventEmitterAsyncResource
} from
'node:events'
4 import { SHARE_ENV
, Worker
} from
'node:worker_threads'
6 import { WorkerAbstract
} from
'./WorkerAbstract.js'
7 import { EMPTY_FUNCTION
, workerSetVersion
} from
'./WorkerConstants.js'
14 type WorkerSetElement
,
16 } from
'./WorkerTypes.js'
17 import { randomizeDelay
, sleep
} from
'./WorkerUtils.js'
19 export class WorkerSet
extends WorkerAbstract
<WorkerData
> {
20 public readonly emitter
: EventEmitterAsyncResource
| undefined
21 private readonly workerSet
: Set
<WorkerSetElement
>
22 private started
: boolean
23 private workerStartup
: boolean
26 * Creates a new `WorkerSet`.
28 * @param workerScript -
29 * @param workerOptions -
31 constructor (workerScript
: string, workerOptions
: WorkerOptions
) {
32 super(workerScript
, workerOptions
)
33 if (this.workerOptions
.elementsPerWorker
== null) {
34 throw new TypeError('Elements per worker is not defined')
36 if (!Number.isSafeInteger(this.workerOptions
.elementsPerWorker
)) {
37 throw new TypeError('Elements per worker must be an integer')
40 typeof this.workerOptions
.elementsPerWorker
=== 'number' &&
41 this.workerOptions
.elementsPerWorker
<= 0
43 throw new RangeError('Elements per worker must be greater than zero')
45 this.workerSet
= new Set
<WorkerSetElement
>()
46 if (this.workerOptions
.poolOptions
?.enableEvents
=== true) {
47 this.emitter
= new EventEmitterAsyncResource({ name
: 'workerset' })
50 this.workerStartup
= false
53 get
info (): SetInfo
{
55 version
: workerSetVersion
,
58 started
: this.started
,
60 elementsExecuting
: [...this.workerSet
].reduce(
61 (accumulator
, workerSetElement
) => accumulator
+ workerSetElement
.numberOfWorkerElements
,
64 // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
65 elementsPerWorker
: this.maxElementsPerWorker
!
70 return this.workerSet
.size
73 get
maxElementsPerWorker (): number | undefined {
74 return this.workerOptions
.elementsPerWorker
78 public async start (): Promise
<void> {
79 this.addWorkerSetElement()
80 // Add worker set element sequentially to optimize memory at startup
81 // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
82 this.workerOptions
.workerStartDelay
! > 0 &&
83 // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
84 (await sleep(randomizeDelay(this.workerOptions
.workerStartDelay
!)))
85 this.emitter
?.emit(WorkerSetEvents
.started
, this.info
)
90 public async stop (): Promise
<void> {
91 for (const workerSetElement
of this.workerSet
) {
92 const worker
= workerSetElement
.worker
93 const waitWorkerExit
= new Promise
<void>(resolve
=> {
94 worker
.once('exit', () => {
99 await worker
.terminate()
102 this.emitter
?.emit(WorkerSetEvents
.stopped
, this.info
)
104 this.emitter
?.emitDestroy()
108 public async addElement (elementData
: WorkerData
): Promise
<void> {
110 throw new Error('Cannot add a WorkerSet element: not started')
112 const workerSetElement
= await this.getWorkerSetElement()
113 workerSetElement
.worker
.postMessage({
114 event
: WorkerMessageEvents
.addWorkerElement
,
117 ++workerSetElement
.numberOfWorkerElements
118 // Add element sequentially to optimize memory at startup
119 // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
120 if (this.workerOptions
.elementAddDelay
! > 0) {
121 // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
122 await sleep(randomizeDelay(this.workerOptions
.elementAddDelay
!))
127 * Adds a new `WorkerSetElement`.
129 private addWorkerSetElement (): WorkerSetElement
{
130 this.workerStartup
= true
131 const worker
= new Worker(this.workerScript
, {
133 ...this.workerOptions
.poolOptions
?.workerOptions
135 worker
.on('message', this.workerOptions
.poolOptions
?.messageHandler
?? EMPTY_FUNCTION
)
136 worker
.on('message', (message
: WorkerMessage
<WorkerData
>) => {
137 if (message
.event
=== WorkerMessageEvents
.addedWorkerElement
) {
138 this.emitter
?.emit(WorkerSetEvents
.elementAdded
, this.info
)
139 } else if (message
.event
=== WorkerMessageEvents
.workerElementError
) {
140 this.emitter
?.emit(WorkerSetEvents
.elementError
, message
.data
)
143 worker
.on('error', this.workerOptions
.poolOptions
?.errorHandler
?? EMPTY_FUNCTION
)
144 worker
.on('error', error
=> {
145 this.emitter
?.emit(WorkerSetEvents
.error
, error
)
147 this.workerOptions
.poolOptions
?.restartWorkerOnError
=== true &&
151 this.addWorkerSetElement()
154 worker
.terminate().catch((error
: unknown
) => this.emitter
?.emit(WorkerSetEvents
.error
, error
))
156 worker
.on('online', this.workerOptions
.poolOptions
?.onlineHandler
?? EMPTY_FUNCTION
)
157 worker
.on('exit', this.workerOptions
.poolOptions
?.exitHandler
?? EMPTY_FUNCTION
)
158 worker
.once('exit', () => {
159 this.removeWorkerSetElement(this.getWorkerSetElementByWorker(worker
))
161 const workerSetElement
: WorkerSetElement
= { worker
, numberOfWorkerElements
: 0 }
162 this.workerSet
.add(workerSetElement
)
163 this.workerStartup
= false
164 return workerSetElement
167 private removeWorkerSetElement (workerSetElement
: WorkerSetElement
| undefined): void {
168 if (workerSetElement
== null) {
171 this.workerSet
.delete(workerSetElement
)
174 private async getWorkerSetElement (): Promise
<WorkerSetElement
> {
175 let chosenWorkerSetElement
: WorkerSetElement
| undefined
176 for (const workerSetElement
of this.workerSet
) {
177 // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
178 if (workerSetElement
.numberOfWorkerElements
< this.workerOptions
.elementsPerWorker
!) {
179 chosenWorkerSetElement
= workerSetElement
183 if (chosenWorkerSetElement
== null) {
184 chosenWorkerSetElement
= this.addWorkerSetElement()
185 // Add worker set element sequentially to optimize memory at startup
186 // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
187 this.workerOptions
.workerStartDelay
! > 0 &&
188 // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
189 (await sleep(randomizeDelay(this.workerOptions
.workerStartDelay
!)))
191 return chosenWorkerSetElement
194 private getWorkerSetElementByWorker (worker
: Worker
): WorkerSetElement
| undefined {
195 let workerSetElt
: WorkerSetElement
| undefined
196 for (const workerSetElement
of this.workerSet
) {
197 if (workerSetElement
.worker
.threadId
=== worker
.threadId
) {
198 workerSetElt
= workerSetElement