Tiny retry ✨

A lightweight module (~0.5kb) to retry an async job until the job success or stop after a maximum number of tries

Usage

• Install package

   npm install tiny-retry
   # or yarn add tiny-retry

• Use it

   import retry from "tiny-retry";
  
   // Async context
   const result = await retry(asyncJob, options);
  
   if (result.success) {
   	// Do something with job data
   	console.log(result.data)
   } else {
   	// Do other thing
   }

Parameters

const result = await retry(asyncJob, { maxTries, delay, startAfter, process, errorHandler, check });

• asyncJob [Function]: async function that throw an Error if failed
• options [Object]: Retry options
  • options.maxTries [Number]: number of maximum time to try to run job
  • options.delay [Number]: the number in miliseconds of time after between each tries
  • options.starAfter [Number]: the number in miliseconds to start the 1st try
  • options.process [Function]: A process function to run before each try with the tries count argument
  • options.errorHandler [Function]: A function to handle error in each try with the err argument
  • options.check [Function]: A function with the job reponse argument to verify whether the job response is expected or not (throw an Error if not)

Return value

• result [Object]: Represent the value of the job done or not and include job's data (if job return)
  • result.success [Boolean]: Whether the job success or not
  • result.tries [Number]: Number of tries
  • [result.data] [Number]: The return value of job if success

console.log(result)

// Expect: { success: true, data: "Async job data", tries }
// If job failed: { success: false, tries }

Example

import retry from "tiny-retry";

const wait = (secs) => new Promise((resolve) => setTimeout(resolve, secs));

let count = 0;
const fakeJobThatDoneAfter6Tries = async () => {
	await wait(2000);
	count += 1;
	if (count < 4) {
		throw new Error('Job failed!');
	} else if (count < 6) {
		return false
	} else {
		console.log('Job done!');
		return "Job data"
	}
};

(async () => {
	console.log("Start Job");
	console.time("JOB_COST");
	const result = await retry(fakeJobThatDoneAfter6Tries, {
		process: (tries) => console.log(`[TRY]: ${tries} time(s)`),
		errorHandler: (err) => console.log(err.toString()),
		check: Boolean,
		maxTries: 10,
		delay: 1000,
		startAfter: 0
	});
	console.log("Job result: ", result);
	console.log("Time expect: 0 + 2*6 + 1*(6-1) = 17s");
	console.timeEnd("JOB_COST"); // Expect 17s
})();

License

Bundled by me from the ideas' combination of me and my friend.

Copyright (c) 2021 Leo Huynh @ https://leohuynh.dev under MIT LICENSE