65 lines
1.7 KiB
JavaScript
65 lines
1.7 KiB
JavaScript
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import debug from 'debug';
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import { sleep } from './util.mjs';
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const log = debug('youtube-maze:retry');
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/**
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* An error that is expected to be temporary such that the initial action
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* may be retried.
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*/
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export class TemporaryError extends Error
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{
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constructor(message)
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{
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super(message);
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this.name = this.constructor.name;
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Error.captureStackTrace(this, this.constructor);
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}
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}
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/**
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* Make an async function retry-able.
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*
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* When the underlying function throws a TemporaryError, the initial
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* call will be repeated, under the limits set below.
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*
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* @param function func Async function to call.
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* @param number retries Allowed number of retries before failing.
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* @param number cooldown Time to wait before retrying (ms).
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* @return function New function that is retryable.
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*/
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export const retryable = (func, retries = 3, cooldown = 1000) =>
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{
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return async (...args) =>
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{
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while (true)
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{
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let remRetries = retries;
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let curCooldown = cooldown;
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try
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{
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const result = await func(...args);
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return result;
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}
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catch (err)
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{
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if (err instanceof TemporaryError && remRetries > 0)
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{
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log(`\
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${func.name}(${args}) failed with error "${err.message}"
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Retrying in ${curCooldown} ms (${remRetries} retries remaining)`);
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await sleep(curCooldown);
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remRetries -= 1;
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curCooldown *= 2;
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}
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else
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{
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throw err;
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}
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}
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}
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};
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};
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