JS: Poll until condition is true (with max attempts and manual abort)

poll.ts

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import { delay } from '../time'

type PollValueCallback<T> = () => Promise<T>

type PollConditionCallback<T> = (t: T) => boolean

interface PollOptions {
  ms?: number
  max?: number
  signal?: AbortSignal
}

// Repetitively run an async function (like requesting data) until its condition succeeds.
// A good sample use-case would be checking that a transaction status changed.
// This is not the function to repetitively load data in attempt to update it every x seconds.
//
// It's very important that you either use the built-in max attempt options
// or provide an AbortController so you are able to opt out of the function.
// Otherwise, this function may run forever, and you might not know it - that's not very good.
//
// We have no strong opinions regarding throwing a function.
// It's wise to silence the errors yourself for now if you want to keep running the poll
// function even if the async function (like requestingng data) fails.
export async function poll<T = unknown>(
  callback: PollValueCallback<T>,
  condition: PollConditionCallback<T>,
  { ms = Infinity, max = Infinity, signal }: PollOptions
): Promise<T | undefined> {
  for (let attempts = 0; attempts < max; attempts++) {
    if (signal?.aborted) {
      return undefined
    }

    const value = await callback()

    if (condition(value) === true) {
      return value
    }

    await delay(ms)
  }

  return undefined
}