42 lines
1.1 KiB
TypeScript
42 lines
1.1 KiB
TypeScript
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export class RequestQueue<T> {
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private pendingPromise = false;
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private items: Array<{
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action: (prevPayload?: T | null) => Promise<T>;
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resolve: (value: T) => void;
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reject: (reason?: any) => void;
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}> = [];
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enqueue(action: (prevPayload?: T | null) => Promise<T>) {
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return new Promise((resolve, reject) => {
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if (this.items.length === 2) {
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this.items[1] = { action, resolve, reject };
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} else {
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this.items.push({ action, resolve, reject });
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}
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this.dequeue();
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});
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}
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async dequeue(prevPayload?: T | null) {
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if (this.pendingPromise) return;
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const item = this.items.shift();
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if (!item) return;
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let payload: T | null = null;
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try {
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this.pendingPromise = true;
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payload = await item.action(prevPayload);
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this.pendingPromise = false;
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item.resolve(payload);
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} catch (e) {
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this.pendingPromise = false;
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item.reject(e);
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} finally {
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this.dequeue(payload);
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}
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}
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}
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