29 lines
633 B
TypeScript
29 lines
633 B
TypeScript
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/**
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* Async concurrency semaphore — limits the number of concurrent async operations.
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*/
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export class ConcurrencySemaphore {
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private running = 0;
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private waitQueue: Array<() => void> = [];
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constructor(private readonly maxConcurrency: number) {}
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async acquire(): Promise<void> {
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if (this.running < this.maxConcurrency) {
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this.running++;
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return;
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}
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return new Promise<void>((resolve) => {
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this.waitQueue.push(() => {
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this.running++;
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resolve();
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});
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});
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}
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release(): void {
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this.running--;
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const next = this.waitQueue.shift();
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if (next) next();
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}
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}
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