Scalable Frontend - The State Layer - Normalization Functions

scalable-front-end-the-state-layer-normalization-functions.js

const replaceRelationById = (entities, relation, idKey = 'id') => entities.map(item => ({
  ...item,
  [relation]: item[relation][idKey],
}))

const extractRelation = (entities, relation) => entities.map(entity => entity[relation])

const byId = (entities, idKey = 'id') => entities
  .reduce((obj, entity) => ({
    ...obj,
    [entity[idKey]]: entity,
  }), {})

const allIds = (entities, idKey = 'id') => [...new Set(entities.map(entity => entity[idKey]))]