redux-saga-simpler.js

import { call, cps, fork, take, put } from 'redux-saga'

/**
 * Create a saga.
 *
 * @param {Object} opts
 * @return {Generator}
 */

export function createSaga(opts) {
  return function* (getState) {
    for (var key in opts) {
      var gen = wrapFork(key, opts[key])
      yield fork(gen, getState)
    }
  }
}

/**
 * Wrap a `generator` function to only be invoked on actions of `type`.
 *
 * @param {String} type
 * @param {Generator} generator
 */

function wrapFork(type, generator) {
  return function* (getState) {
    while (true) {
      const action = yield take(type)
      const store = { dispatch: put, getState }
      yield generator(action, store)
    }
  }
}

/**
 * Wrap a promise-returning `fn` for testability.
 *
 * @param {Function} fn
 * @return {Function}
 */

export function wrap(fn) {
  return function (...args) {
    return call(fn, ...args)
  }
}

/**
 * Wrap a thunk-returning `fn` for testability.
 *
 * @param {Function} fn
 * @return {Function}
 */

export function wrapThunk(fn) {
  return function (...args) {
    return cps(fn, ...args)
  }
}