Error handling on action payload about redux-actions

[archywillhe]

:(

[simondell]

Flux Standard Actions, which redux-actions providers helpers for, represent success and error "versions" of an action as the same action type. createAction() will create action-creator functions which accept either a value or an error object. When the code which may have success or error paths needs to dispatch an action, you can use the same action creator.

// action creators.js
const readDataCompleted = createAction('DATA/READ_COMPLETED`)

// getdata.js
import somethingHappened from './actions'
import store from './store'

try {
  const response = await fetch('some_url')
  
  if(!response.ok) throw new Error('Bad times on the internetz.')

  const body = await response.json()
  store.dispatch(somethingHappened(body))
}
catch (err) {
  store.dispatch(somethingHappened(err))
}

Code similar to this will produce a "success" action when following the happy path:

{
  type: 'DATA/READ_COMPLETED',
  payload: /* ... your data ... */
}

... and an 'error' action when following the error path:

{
  type: 'DATA/READ_COMPLETED',
  error: { message: 'Bad times on the internetz.' }
}
// well, it'll be a proper error object, not the pseudo-error object I wrote above.

This means that your reducers need to contain logic for handling the success and error states. You can roll your own, or use handleAction()/handleActions(), also included in the redux-actions library, to help create these "error aware" reducers. I'll leave you to look at the docs for handleAction().