Redux Middleware for async actions

• FSA
• Promise based

Usage example

• Actions creators

const githubFetching = createAction(GITHUB_FETCHING)
const githubError    = createAction(GITHUB_ERROR)
const githubSuccess  = createAction(GITHUB_SUCCESS)

• Create an action passing all action creators and the api call method

export const getUserFromGithub = username => ({
  type : [
    githubFetching,
    githubSuccess,
    githubError
  ],
  payload : {
    data : () => axios.get(`https://api.github.com/users/${username}`)
  }
})

• type is an Array with actions creators
• payload must have data property and it must to be a function that returns a Promise

Note: you can pass more properties inside payload and it will be passed to success action.

Basic flow: loginSending -> data -> loginSuccess / loginError

The middleware will call loginSending before apiCall and loginSuccess when promise got resolved, if got an error, loginError will be called.

Reducer / Action creators example (with redux-actions)

• Actions types

export const GITHUB_FETCHING = 'modules/Github/FETCHING'
export const GITHUB_SUCCESS  = 'modules/Github/SUCCESS'
export const GITHUB_ERROR    = 'modules/Github/ERROR'

• Reducer

import {handleActions} from 'redux-actions'

import {GITHUB_FETCHING, GITHUB_SUCCESS, GITHUB_ERROR} from './actions'

const initialState = {
  fetching : false,
  user     : null
}

const reducer = handleActions({
  [GITHUB_FETCHING]: (state, action) => ({
    ...state,
    sending     : true
  }),

  [GITHUB_SUCCESS]: (state, action) => ({
    sending     : false,
    user        : action.payload.data
  }),

  [GITHUB_ERROR]: (state, action) => ({
    ...state,
    sending     : false,
  })

}, initialState);

export default reducer

Example without redux-actions

const githubFetching = () => ({ type : 'GITHUB_FETCHING' })
const githubError    = () => ({ type : 'GITHUB_ERROR' })
const githubSuccess  = payload => ({
  type    : 'GITHUB_SUCCESS',
  payload : payload
})

const initialState = {
  fetching : false,
  user     : null
}

export const getUserFromGithub = username => ({
  type : [
    githubFetching,
    githubSuccess,
    githubError
  ],
  payload : {
      data : () => axios.get(`https://api.github.com/users/${username}`)
  }
})

export default (state = initialState, action) => {
  switch (action.type) {
    case 'GITHUB_FETCHING':
      return {...state,
              fetching     : true
              }
    case 'GITHUB_SUCCESS':
      return {...state,
              fetching     : false,
              user         : action.payload.data
              }
    case 'GITHUB_ERROR':
      return {...state,
              fetching       : false
            }
    default:
      return state
  }
}

Another Note: You have to pass the default methods to dispatch in case of success or failure, but the middleware will always return a Promise. So if you need to do something after dispatch these methods, you are able to use:

dispatch(myAction())
// here we got the dispatch of success or failure and then...
.then()
.catch()
// and so on