Run with limit

Run promise-returning & async functions with limited concurrency. Heavily inspired by sindresorhus/p-limit.

Usage

import { makeRunWithLimit } from "https://denopkg.com/alextes/run-with-limit";

const { runWithLimit } = makeRunWithLimit(1);

(async () => {
  // Only one promise is run at once
  const result = await Promise.all([
    runWithLimit(() => fetchSomething("foo")),
    runWithLimit(() => fetchSomething("bar")),
    runWithLimit(() => doSomething()),
  ]);
  console.log(result);
})();

API

makeRunWithLimit(concurrency)

Number => { runWithLimit, getActiveCount, getPendingCount }

Takes a number, setting the concurrency for the promise queue. Returns a set of functions to use the queue.

runWithLimit

<A>(() => Promise<A>) => Promise<A>

Pass a thunk to this function that returns a promise.

That is, pass a function which when invoked, kicks off an asynchronous computation, and if you need its result, returns a promise. runWithLimit will resolve with said result while honoring the concurrency limit.

getActiveCount

() => Number

Call to get the number of promises that are currently running.

getPendingCount

() => Number

Call to check how many promises are still waiting to start execution.