35 lines
723 B
TypeScript
35 lines
723 B
TypeScript
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export default class CachePromise<DataType = any> {
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expireTime: number;
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curTm: number = 0;
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promise: Promise<DataType> | undefined;
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pf: () => Promise<DataType>;
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constructor(pf: () => Promise<DataType>, expireTime?: number) {
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this.pf = pf;
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this.expireTime = expireTime || 0;
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}
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setNull = () => {
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this.promise = undefined;
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}
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get = async () => {
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const now = Date.now();
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if (this.expireTime && now - this.curTm > this.expireTime) {
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this.promise = this.pf();
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this.curTm = now;
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}
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if (!this.promise) {
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this.promise = this.pf();
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this.curTm = now;
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}
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const data = await this.promise;
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if (!data) {
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this.setNull();
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}
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return data;
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}
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}
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