reducers_ex.js

const PUBLICIZE_SHARE = 'PUBLICIZE_SHARE';
const PUBLICIZE_SHARE_SUCCESS = 'PUBLICIZE_SHARE_SUCCESS';
const PUBLICIZE_SHARE_FAILURE = 'PUBLICIZE_SHARE_FAILURE';
const PUBLICIZE_SHARE_DISMISS = 'PUBLICIZE_SHARE_DISMISS';

const sharePostStatus = {
  [ PUBLICIZE_SHARE ]: ( state, { siteId, postId } ) => 
    ( { ...state, [ siteId ]: { ...state[ siteId ], [ postId ]: {
		  requesting: true,
	  } } } ),
  [ PUBLICIZE_SHARE_SUCCESS ]: ( state, { siteId, postId } ) => 
    ( { ...state, [ siteId ]: { ...state[ siteId ], [ postId ]: {
		  requesting: false,
		  success: true,
	  } } } ),
  [ PUBLICIZE_SHARE_FAILURE ]: ( state, { siteId, postId, error } ) => 
    ( { ...state, [ siteId ]: { ...state[ siteId ], [ postId ]: {
		  requesting: false,
		  success: false,
		  error,
	  } } } ),
  [ PUBLICIZE_SHARE_DISMISS ]: ( state, { siteId, postId } ) => 
    ( { ...state, [ siteId ]: {
		  ...state[ siteId ], [ postId ]: undefined
	  } } ),
};