Task

task.js

const fetch = require('node-fetch')
const Task = require('data.task')

const KEY = 'KEY!'

const asteroidRequest = new Task((reject, resolve) => (
  fetch(`https://api.nasa.gov/neo/rest/v1/feed?start_date=2016-05-05&end_date=2016-05-05&api_key=${KEY}`)
    .then((res) => res.json())
    .then(resolve)
    .catch(reject)
))

const logged = asteroidRequest.map((res) => {
  console.log('FIRST')
  return res
})

const anotherAseroidRequest = new Task((reject, resolve) => (
  fetch(`https://api.nasa.gov/neo/rest/v1/feed?start_date=2016-05-05&end_date=2016-05-06&api_key=${KEY}`)
    .then((res) => res.json())
    .then(resolve)
    .catch(reject)
))

const anotherLogged = anotherAseroidRequest.map((res) => {
  console.log('SECOND')
  return res
})

const yetAnotherAseroidRequest = new Task((reject, resolve) => (
  fetch(`https://api.nasa.gov/neo/rest/v1/feed?start_date=2016-05-06&end_date=2016-05-07&api_key=${KEY}`)
    .then((res) => res.json())
    .then(resolve)
    .catch(reject)
))

const yetAnotherLogged = yetAnotherAseroidRequest.map((res) => {
  console.log('THIRD')
  return res
})

const series = logged.chain((a) => anotherLogged.map((b) => [a, b]))

series.fork((err) => {}, (res) => { console.log('SERIES: ', res) })

// concat :: (Semigroup a) => Task a -> Task a -> Task a
const concat = (taskA, taskB) => (
  Task.of((a) => (b) => a.concat(b))
    .ap(taskA)
    .ap(taskB)
)

// all :: (Semigroup a) => [Task a] -> Task a
const all = (tasks) => (
  tasks.reduce((acc, task) => (
    concat(acc, task)
  ))
)

const parallel = all([
  logged.map(Array),
  anotherLogged.map(Array),
  yetAnotherLogged.map(Array)
])

parallel.fork((err) => {}, (res) => { console.log('PARALLEL: ', res) })