52 lines
1.4 KiB
TypeScript
52 lines
1.4 KiB
TypeScript
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/*
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This file is part of GNU Taler
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(C) 2019 GNUnet e.V.
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GNU Taler is free software; you can redistribute it and/or modify it under the
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terms of the GNU General Public License as published by the Free Software
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Foundation; either version 3, or (at your option) any later version.
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GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
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WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
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A PARTICULAR PURPOSE. See the GNU General Public License for more details.
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You should have received a copy of the GNU General Public License along with
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GNU Taler; see the file COPYING. If not, see <http://www.gnu.org/licenses/>
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*/
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export interface MemoEntry<T> {
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p: Promise<T>;
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t: number;
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n: number;
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}
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export class AsyncOpMemo<T> {
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n = 0;
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memo: { [k: string]: MemoEntry<T> } = {};
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put(key: string, p: Promise<T>): Promise<T> {
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const n = this.n++;
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this.memo[key] = {
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p,
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n,
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t: new Date().getTime(),
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};
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p.finally(() => {
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const r = this.memo[key];
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if (r && r.n === n) {
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delete this.memo[key];
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}
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});
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return p;
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}
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find(key: string): Promise<T> | undefined {
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const res = this.memo[key];
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const tNow = new Date().getTime();
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if (res && res.t < tNow - 10 * 1000) {
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delete this.memo[key];
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return;
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} else if (res) {
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return res.p;
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}
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return;
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}
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}
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