limit-fn-parallelism

Makes your function only be called with a maximum concurrency limit. Further calls are enqueued to be returned later.

Synopsis

const limitFnParallelism = require('limit-fn-parallelism')
const limitedFn = limitFn(async function expensiveFn(arg1, arg2) {
    // do something expensive asynchronously...
}, 2)

const results = await Promise.all([
    limitedFn(1, 2), // Starts right away
    limitedFn(3, 4), // Starts right away
    limitedFn(5, 6)  // Only starts when one of the others finish
])

const limited = limitFnParallelism(asyncFn, [limit = 1])

Returns a limited version of the input function.

limited.concurrentCalls

The number of executions going on at this moment in time.

await limited.allFinished()

Waits for all calls to have returned (or thrown) limited.concurrentCalls will be zero.