forked from ddrilling/asb_cloud_front
29 lines
640 B
TypeScript
29 lines
640 B
TypeScript
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export type TaskHandler<T> = () => T | PromiseLike<T>
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export type Queue<T> = {
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push: (task: TaskHandler<T>) => Promise<T>
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readonly length: number
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}
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export const makeTaskQueue = <T,>(): Queue<T> => {
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let pending: Promise<T | void> = Promise.resolve()
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let count: number = 0
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const run = async (task?: TaskHandler<T>) => {
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count++
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try {
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await pending;
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} finally {
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count--
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return Promise.resolve().then(task);
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}
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}
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return {
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push: (task: TaskHandler<T>) => pending = run(task),
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length: count,
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}
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}
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export default makeTaskQueue
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