| 1 | import { EventEmitter } from 'node:events' |
| 2 | import { type TransferListItem } from 'node:worker_threads' |
| 3 | import type { TaskFunction } from '../worker/task-functions' |
| 4 | import type { |
| 5 | ErrorHandler, |
| 6 | ExitHandler, |
| 7 | IWorker, |
| 8 | IWorkerNode, |
| 9 | MessageHandler, |
| 10 | OnlineHandler, |
| 11 | WorkerType |
| 12 | } from './worker' |
| 13 | import type { |
| 14 | WorkerChoiceStrategy, |
| 15 | WorkerChoiceStrategyOptions |
| 16 | } from './selection-strategies/selection-strategies-types' |
| 17 | |
| 18 | /** |
| 19 | * Enumeration of pool types. |
| 20 | */ |
| 21 | export const PoolTypes = Object.freeze({ |
| 22 | /** |
| 23 | * Fixed pool type. |
| 24 | */ |
| 25 | fixed: 'fixed', |
| 26 | /** |
| 27 | * Dynamic pool type. |
| 28 | */ |
| 29 | dynamic: 'dynamic' |
| 30 | } as const) |
| 31 | |
| 32 | /** |
| 33 | * Pool type. |
| 34 | */ |
| 35 | export type PoolType = keyof typeof PoolTypes |
| 36 | |
| 37 | /** |
| 38 | * Pool events emitter. |
| 39 | */ |
| 40 | export class PoolEmitter extends EventEmitter {} |
| 41 | |
| 42 | /** |
| 43 | * Enumeration of pool events. |
| 44 | */ |
| 45 | export const PoolEvents = Object.freeze({ |
| 46 | ready: 'ready', |
| 47 | busy: 'busy', |
| 48 | full: 'full', |
| 49 | destroy: 'destroy', |
| 50 | error: 'error', |
| 51 | taskError: 'taskError', |
| 52 | backPressure: 'backPressure' |
| 53 | } as const) |
| 54 | |
| 55 | /** |
| 56 | * Pool event. |
| 57 | */ |
| 58 | export type PoolEvent = keyof typeof PoolEvents |
| 59 | |
| 60 | /** |
| 61 | * Pool information. |
| 62 | */ |
| 63 | export interface PoolInfo { |
| 64 | readonly version: string |
| 65 | readonly type: PoolType |
| 66 | readonly worker: WorkerType |
| 67 | readonly started: boolean |
| 68 | readonly ready: boolean |
| 69 | readonly strategy: WorkerChoiceStrategy |
| 70 | readonly minSize: number |
| 71 | readonly maxSize: number |
| 72 | /** Pool utilization. */ |
| 73 | readonly utilization?: number |
| 74 | /** Pool total worker nodes. */ |
| 75 | readonly workerNodes: number |
| 76 | /** Pool idle worker nodes. */ |
| 77 | readonly idleWorkerNodes: number |
| 78 | /** Pool busy worker nodes. */ |
| 79 | readonly busyWorkerNodes: number |
| 80 | readonly executedTasks: number |
| 81 | readonly executingTasks: number |
| 82 | readonly queuedTasks?: number |
| 83 | readonly maxQueuedTasks?: number |
| 84 | readonly backPressure?: boolean |
| 85 | readonly stolenTasks?: number |
| 86 | readonly failedTasks: number |
| 87 | readonly runTime?: { |
| 88 | readonly minimum: number |
| 89 | readonly maximum: number |
| 90 | readonly average?: number |
| 91 | readonly median?: number |
| 92 | } |
| 93 | readonly waitTime?: { |
| 94 | readonly minimum: number |
| 95 | readonly maximum: number |
| 96 | readonly average?: number |
| 97 | readonly median?: number |
| 98 | } |
| 99 | } |
| 100 | |
| 101 | /** |
| 102 | * Worker node tasks queue options. |
| 103 | */ |
| 104 | export interface TasksQueueOptions { |
| 105 | /** |
| 106 | * Maximum tasks queue size per worker node flagging it as back pressured. |
| 107 | * |
| 108 | * @defaultValue (pool maximum size)^2 |
| 109 | */ |
| 110 | readonly size?: number |
| 111 | /** |
| 112 | * Maximum number of tasks that can be executed concurrently on a worker node. |
| 113 | * |
| 114 | * @defaultValue 1 |
| 115 | */ |
| 116 | readonly concurrency?: number |
| 117 | /** |
| 118 | * Whether to enable task stealing. |
| 119 | * |
| 120 | * @defaultValue true |
| 121 | */ |
| 122 | readonly taskStealing?: boolean |
| 123 | /** |
| 124 | * Whether to enable tasks stealing on back pressure. |
| 125 | * |
| 126 | * @defaultValue true |
| 127 | */ |
| 128 | readonly tasksStealingOnBackPressure?: boolean |
| 129 | } |
| 130 | |
| 131 | /** |
| 132 | * Options for a poolifier pool. |
| 133 | * |
| 134 | * @typeParam Worker - Type of worker. |
| 135 | */ |
| 136 | export interface PoolOptions<Worker extends IWorker> { |
| 137 | /** |
| 138 | * A function that will listen for online event on each worker. |
| 139 | */ |
| 140 | onlineHandler?: OnlineHandler<Worker> |
| 141 | /** |
| 142 | * A function that will listen for message event on each worker. |
| 143 | */ |
| 144 | messageHandler?: MessageHandler<Worker> |
| 145 | /** |
| 146 | * A function that will listen for error event on each worker. |
| 147 | */ |
| 148 | errorHandler?: ErrorHandler<Worker> |
| 149 | /** |
| 150 | * A function that will listen for exit event on each worker. |
| 151 | */ |
| 152 | exitHandler?: ExitHandler<Worker> |
| 153 | /** |
| 154 | * Whether to start the minimum number of workers at pool initialization. |
| 155 | * |
| 156 | * @defaultValue true |
| 157 | */ |
| 158 | startWorkers?: boolean |
| 159 | /** |
| 160 | * The worker choice strategy to use in this pool. |
| 161 | * |
| 162 | * @defaultValue WorkerChoiceStrategies.ROUND_ROBIN |
| 163 | */ |
| 164 | workerChoiceStrategy?: WorkerChoiceStrategy |
| 165 | /** |
| 166 | * The worker choice strategy options. |
| 167 | */ |
| 168 | workerChoiceStrategyOptions?: WorkerChoiceStrategyOptions |
| 169 | /** |
| 170 | * Restart worker on error. |
| 171 | */ |
| 172 | restartWorkerOnError?: boolean |
| 173 | /** |
| 174 | * Pool events emission. |
| 175 | * |
| 176 | * @defaultValue true |
| 177 | */ |
| 178 | enableEvents?: boolean |
| 179 | /** |
| 180 | * Pool worker node tasks queue. |
| 181 | * |
| 182 | * @defaultValue false |
| 183 | */ |
| 184 | enableTasksQueue?: boolean |
| 185 | /** |
| 186 | * Pool worker node tasks queue options. |
| 187 | */ |
| 188 | tasksQueueOptions?: TasksQueueOptions |
| 189 | } |
| 190 | |
| 191 | /** |
| 192 | * Contract definition for a poolifier pool. |
| 193 | * |
| 194 | * @typeParam Worker - Type of worker which manages this pool. |
| 195 | * @typeParam Data - Type of data sent to the worker. This can only be structured-cloneable data. |
| 196 | * @typeParam Response - Type of execution response. This can only be structured-cloneable data. |
| 197 | */ |
| 198 | export interface IPool< |
| 199 | Worker extends IWorker, |
| 200 | Data = unknown, |
| 201 | Response = unknown |
| 202 | > { |
| 203 | /** |
| 204 | * Pool information. |
| 205 | */ |
| 206 | readonly info: PoolInfo |
| 207 | /** |
| 208 | * Pool worker nodes. |
| 209 | * |
| 210 | * @internal |
| 211 | */ |
| 212 | readonly workerNodes: Array<IWorkerNode<Worker, Data>> |
| 213 | /** |
| 214 | * Whether the worker node has back pressure (i.e. its tasks queue is full). |
| 215 | * |
| 216 | * @param workerNodeKey - The worker node key. |
| 217 | * @returns `true` if the worker node has back pressure, `false` otherwise. |
| 218 | * @internal |
| 219 | */ |
| 220 | readonly hasWorkerNodeBackPressure: (workerNodeKey: number) => boolean |
| 221 | /** |
| 222 | * Emitter on which events can be listened to. |
| 223 | * |
| 224 | * Events that can currently be listened to: |
| 225 | * |
| 226 | * - `'ready'`: Emitted when the number of workers created in the pool has reached the minimum size expected and are ready. |
| 227 | * - `'busy'`: Emitted when the number of workers created in the pool has reached the maximum size expected and are executing concurrently their tasks quota. |
| 228 | * - `'full'`: Emitted when the pool is dynamic and the number of workers created has reached the maximum size expected. |
| 229 | * - `'destroy'`: Emitted when the pool is destroyed. |
| 230 | * - `'error'`: Emitted when an uncaught error occurs. |
| 231 | * - `'taskError'`: Emitted when an error occurs while executing a task. |
| 232 | * - `'backPressure'`: Emitted when all worker nodes have back pressure (i.e. their tasks queue is full: queue size \>= maximum queue size). |
| 233 | */ |
| 234 | readonly emitter?: PoolEmitter |
| 235 | /** |
| 236 | * Executes the specified function in the worker constructor with the task data input parameter. |
| 237 | * |
| 238 | * @param data - The optional task input data for the specified task function. This can only be structured-cloneable data. |
| 239 | * @param name - The optional name of the task function to execute. If not specified, the default task function will be executed. |
| 240 | * @param transferList - An optional array of transferable objects to transfer ownership of. Ownership of the transferred objects is given to the pool's worker_threads worker and they should not be used in the main thread afterwards. |
| 241 | * @returns Promise that will be fulfilled when the task is completed. |
| 242 | */ |
| 243 | readonly execute: ( |
| 244 | data?: Data, |
| 245 | name?: string, |
| 246 | transferList?: TransferListItem[] |
| 247 | ) => Promise<Response> |
| 248 | /** |
| 249 | * Starts the minimum number of workers in this pool. |
| 250 | */ |
| 251 | readonly start: () => void |
| 252 | /** |
| 253 | * Terminates all workers in this pool. |
| 254 | */ |
| 255 | readonly destroy: () => Promise<void> |
| 256 | /** |
| 257 | * Whether the specified task function exists in this pool. |
| 258 | * |
| 259 | * @param name - The name of the task function. |
| 260 | * @returns `true` if the task function exists, `false` otherwise. |
| 261 | */ |
| 262 | readonly hasTaskFunction: (name: string) => boolean |
| 263 | /** |
| 264 | * Adds a task function to this pool. |
| 265 | * If a task function with the same name already exists, it will be overwritten. |
| 266 | * |
| 267 | * @param name - The name of the task function. |
| 268 | * @param taskFunction - The task function. |
| 269 | * @returns `true` if the task function was added, `false` otherwise. |
| 270 | */ |
| 271 | readonly addTaskFunction: ( |
| 272 | name: string, |
| 273 | taskFunction: TaskFunction<Data, Response> |
| 274 | ) => Promise<boolean> |
| 275 | /** |
| 276 | * Removes a task function from this pool. |
| 277 | * |
| 278 | * @param name - The name of the task function. |
| 279 | * @returns `true` if the task function was removed, `false` otherwise. |
| 280 | */ |
| 281 | readonly removeTaskFunction: (name: string) => Promise<boolean> |
| 282 | /** |
| 283 | * Lists the names of task function available in this pool. |
| 284 | * |
| 285 | * @returns The names of task function available in this pool. |
| 286 | */ |
| 287 | readonly listTaskFunctionNames: () => string[] |
| 288 | /** |
| 289 | * Sets the default task function in this pool. |
| 290 | * |
| 291 | * @param name - The name of the task function. |
| 292 | * @returns `true` if the default task function was set, `false` otherwise. |
| 293 | */ |
| 294 | readonly setDefaultTaskFunction: (name: string) => Promise<boolean> |
| 295 | /** |
| 296 | * Sets the worker choice strategy in this pool. |
| 297 | * |
| 298 | * @param workerChoiceStrategy - The worker choice strategy. |
| 299 | * @param workerChoiceStrategyOptions - The worker choice strategy options. |
| 300 | */ |
| 301 | readonly setWorkerChoiceStrategy: ( |
| 302 | workerChoiceStrategy: WorkerChoiceStrategy, |
| 303 | workerChoiceStrategyOptions?: WorkerChoiceStrategyOptions |
| 304 | ) => void |
| 305 | /** |
| 306 | * Sets the worker choice strategy options in this pool. |
| 307 | * |
| 308 | * @param workerChoiceStrategyOptions - The worker choice strategy options. |
| 309 | */ |
| 310 | readonly setWorkerChoiceStrategyOptions: ( |
| 311 | workerChoiceStrategyOptions: WorkerChoiceStrategyOptions |
| 312 | ) => void |
| 313 | /** |
| 314 | * Enables/disables the worker node tasks queue in this pool. |
| 315 | * |
| 316 | * @param enable - Whether to enable or disable the worker node tasks queue. |
| 317 | * @param tasksQueueOptions - The worker node tasks queue options. |
| 318 | */ |
| 319 | readonly enableTasksQueue: ( |
| 320 | enable: boolean, |
| 321 | tasksQueueOptions?: TasksQueueOptions |
| 322 | ) => void |
| 323 | /** |
| 324 | * Sets the worker node tasks queue options in this pool. |
| 325 | * |
| 326 | * @param tasksQueueOptions - The worker node tasks queue options. |
| 327 | */ |
| 328 | readonly setTasksQueueOptions: (tasksQueueOptions: TasksQueueOptions) => void |
| 329 | } |