52 lines
1.9 KiB
TypeScript
52 lines
1.9 KiB
TypeScript
/**
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* Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*/
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/// <reference types="node" />
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import { ChildMessage, OnCustomMessage, OnEnd, OnStart, WorkerInterface, WorkerOptions } from '../types';
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/**
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* This class wraps the child process and provides a nice interface to
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* communicate with. It takes care of:
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*
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* - Re-spawning the process if it dies.
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* - Queues calls while the worker is busy.
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* - Re-sends the requests if the worker blew up.
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*
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* The reason for queueing them here (since childProcess.send also has an
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* internal queue) is because the worker could be doing asynchronous work, and
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* this would lead to the child process to read its receiving buffer and start a
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* second call. By queueing calls here, we don't send the next call to the
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* children until we receive the result of the previous one.
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*
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* As soon as a request starts to be processed by a worker, its "processed"
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* field is changed to "true", so that other workers which might encounter the
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* same call skip it.
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*/
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export default class ChildProcessWorker implements WorkerInterface {
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private _child;
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private _options;
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private _request;
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private _retries;
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private _onProcessEnd;
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private _onCustomMessage;
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private _fakeStream;
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private _stdout;
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private _stderr;
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private _exitPromise;
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private _resolveExitPromise;
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constructor(options: WorkerOptions);
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initialize(): void;
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private _shutdown;
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private _onMessage;
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private _onExit;
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send(request: ChildMessage, onProcessStart: OnStart, onProcessEnd: OnEnd, onCustomMessage: OnCustomMessage): void;
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waitForExit(): Promise<void>;
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forceExit(): void;
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getWorkerId(): number;
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getStdout(): NodeJS.ReadableStream | null;
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getStderr(): NodeJS.ReadableStream | null;
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private _getFakeStream;
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}
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