FavoritesActions.js

export const addToFavorites = (item) => ({
  type: types.ADD_TO_FAVORITES,
  item,
});

export const removeFromFavorites = (itemIndex) => ({
  type: types.REMOVE_FROM_FAVORITES,
  itemIndex,
});

export function addItemToFavorites(item) {
  const params = {
    item_id: item.item_id,
  };

  return dispatch =>
    axios.post(api.ADD_ITEM_TO_FAVORITES, params)
      .then(() => dispatch(addToFavorites(item)))
      .catch(err => { throw err; });
}

export function removeItemFromFavorites(item, itemIndex) {
  const params = {
    item_id: item.item_id,
  };

  return dispatch =>
    axios.post(api.REMOVE_ITEM_FROM_FAVORITES, params)
      .then(() => dispatch(removeItemFromFavorites(itemIndex)))
      .catch(err => { throw err; });
}