get-promisable-result

A very small JavaScript utility to check and retry a function a limited number of times abstracting it in a Promise

Install

npm

npm install get-promisable-result

yarn

yarn add get-promisable-result

PNPM

pnpm add get-promisable-result

API

getPromisableResult(
  getResultFunction: () => T,
  checkResult: (result: T) => boolean,
  options: PromisableOptions = {}
): Promise<T>

getResultFunction should be a function that returns something. This something is what you expect when the promise gets resolved.

checkResult is a function that will have as a parameter the result of the getResultFunction and it should return a boolean to validate that the result is OK. If this function returns false, the getResultFunction will be executed a limited number of times (consult the options section) until its result pass the check or until it reached the retries (consult the options section).

Options

| Parameter | Type | Default | Description | | -------------- | ------------- | ------- | ------------------------------------------------------------------- | | retries | number | 10 | number of retries that will be performed before the promise rejects | | delay | number | 10 | delay between the retries | | shouldReject | boolean | true | indicates if the promise should be rejected when the number of retries reached the limit. If this parameter is set to false and the number of retries is reached the Promise will be resolved with the last value returned by getResultFunction | | rejectMessage | string | ** | custom error message. It can contain the substring {{ retries }} and it will be replaced with the number of retries |

** The default rejectMessage will be Could not get the result after {{ retries }} retries

Example

Querying a DOM element that is rendered asynchronously with a custom retries, delay and rejectMessage

getPromisableResult(
  () => document.getElementById('my-element'),
  (element) => element !== null,
  {
    retries: 50,
    delay: 100,
    rejectMessage: 'My element could not be retrieved after {{ restries }} retries'
  }
)
  .then((element) => {
    // Do something with the element
  })
  .catch((error) => {
    // Do something if the promise is rejected
    // My element could not be retrieved after 50 retries
  });