KISS Promise Pool

Creates a local cache. If a value does not exist in cache it using the producer function to get it.

const cachedProducer = require('kiss-cached-producer')
const db = require('a-database-api')

const productGetter = cachedProducer(
  productId => {
    // Got get something from database
    db.getProduct(productId)
  }
)  

const product1 = productGetter(123) // First time will goto the database
const product2 = productGetter(123) // This time will resolve from cache

Sometimes you need to pass a state into the calling function ...

const cachedProducer = require('kiss-cached-producer')
const db = require('a-database-api')

const productGetter = cachedProducer(
  (productId, state)  => {
    // Got get something from database
    state.getProduct(productId)
  },
  db, // This is the program state
)  

const product1 = productGetter(123) // First time will goto the database
const product2 = productGetter(123) // This time will resolve from cache

Sometimes you need to extract the key value from an object...

const cachedProducer = require('kiss-cached-producer')
const db = require('a-database-api')

const productGetter = cachedProducer(
  (productId, state)  => {
    // Got get something from database
    state.getProduct(productId)
  },
  db, // This is the program state
  o => o.productId // A getter function to return the cache key value
)  

const product1 = productGetter({productId:123}) // First time will goto the database
const product2 = productGetter({productId:123}) // This time will resolve from cache