dataloader-results

High order functions for dataloader. It is useful to return compliant results (ordered and same length as ids array)

• Promise aware
• Only vanilla js and optimized

Install

npm i -S dataloader-results

Example

const { orderedResults } = require('dataloader-results');

...

const getObjectsByIds = (ids) => ...
const dataLoader = new DataLoader(orderedResults(getObjectsByIds));

Promise.all([
  dataLoader.load(1),
  dataLoader.load(2),
  dataLoader.load(3),
  dataLoader.load(4),
]).then((r) => {
  ...
})

API

orderedResults()

orderedResults(
  batchFetcher: (ids: a[]) => r[],
  options?: {
    indexer: r => a,
    idGetter: a => b,
  }
): (ids: a[]) => r[]

Accept a function (batchFetcher) that fetch synchronuously or asynchronuously data using ids array.

It returns an array of results with same length as ids array (a[]).

orderedResults() orders results returned by batchFetcher and if a result is missing, it returns null instead of nothing.

options is optional. It can used to define custom indexer and custom idGetter

options.indexer is used to index result array returned by batchFetcher. Return value type must be the same as array of ids. Default indexer is defined to r => r.id;

options.idGetter is used to transform index when creating result array. Default idGetter is defined to id => id. This parameter is useful when a is an object and not an number or string