Fetch API Helpers

fetch-helpers.js

import fetch from 'isomorphic-fetch'

const setupRequestOptions = (options = {}, overrideMethod) => {
  if (overrideMethod) options.method = overrideMethod
  if (!options.headers) options.headers = {}
  options.credentials = 'same-origin'
  return options
}

const setupJsonRequestOptions = (options, overrideMethod) => {
  options = setupRequestOptions(options, overrideMethod)
  options.headers['Accept'] = 'application/json'
  if (options.body) {
    options.headers['Content-Type'] = 'application/json'
    if (typeof options.body !== 'string' || !/^".*"$/g.test(options.body)) {
      options.body = JSON.stringify(options.body)
    }
  }
  return options
}

const getOkAndJsonBody = res =>
  res.json()
    .catch(() => null)
    .then(data => ({ok: res.ok, body: data}))

const checkOk = res => res.ok ? res : Promise.reject(res)
const unwrapBody = res => res.body

export const fetchJsonWithResponse = (url, options, overrideMethod) => {
  options = setupJsonRequestOptions(options, overrideMethod)
  return fetch(url, options)
}

export const fetchJson = (url, options, overrideMethod) => {
  return fetchJsonWithResponse(url, options, overrideMethod)
    .then(getOkAndJsonBody)
    .then(checkOk)
    .then(unwrapBody)
}

export const fetchRaw = (url, options, overrideMethod) => {
  options = setupRequestOptions(options, overrideMethod)
  return fetch(url, options)
}

export const getJson = (url, options) => fetchJson(url, options, 'GET')
export const postJson = (url, options) => fetchJson(url, options, 'POST')
export const putJson = (url, options) => fetchJson(url, options, 'PUT')
export const deleteJson = (url, options) => fetchJson(url, options, 'DELETE')

export const getRaw = (url, options) => fetchRaw(url, options, 'GET')
export const postRaw = (url, options) => fetchRaw(url, options, 'POST')
export const putRaw = (url, options) => fetchRaw(url, options, 'PUT')
export const deleteRaw = (url, options) => fetchRaw(url, options, 'DELETE')