Run multiple promise-returning & async functions with limited concurrency
$ npm install p-limit
import pLimit from 'p-limit'; const limit = pLimit(1); const input = [ limit(() => fetchSomething('foo')), limit(() => fetchSomething('bar')), limit(() => doSomething()) ]; // Only one promise is run at once const result = await Promise.all(input); console.log(result);
Returns the promise returned by calling
Any arguments to pass through to
Support for passing arguments on to the
fn is provided in order to be able to avoid creating unnecessary closures. You probably don't need this optimization unless you're pushing a lot of functions.
The number of promises that are currently running.
The number of promises that are waiting to run (i.e. their internal
fn was not called yet).
Discard pending promises that are waiting to run.
This might be useful if you want to teardown the queue at the end of your program's lifecycle or discard any function calls referencing an intermediary state of your app.
Note: This does not cancel promises that are already running.
How is this different from the
This package is only about limiting the number of concurrent executions, while
p-queue is a fully featured queue implementation with lots of different options, introspection, and ability to pause the queue.
- p-queue - Promise queue with concurrency control
- p-throttle - Throttle promise-returning & async functions
- p-debounce - Debounce promise-returning & async functions
- p-all - Run promise-returning & async functions concurrently with optional limited concurrency
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