redux middlewares

middleware.js

/**
 * bare middleare 
 */
export default function({ dispatch }) {
  return next => action => {
    console.log(action);
    
    // send this action to next middleware or reducers if that's the last middleware
    next(action);
  }
}

/**
 * simple promise middleware 
 * https://www.udemy.com/react-redux-tutorial/learn/v4/t/lecture/4709458
 */
 export default function({ dispatch }) {
  return next => action => {
    // If action does not have payload
    // or, the payload does not have a .then property
    // we dont care about it, send it on
    if (!action.payload || !action.payload.then) {
      return next(action);
    }

    // Make sure the action's promise resolves
    action.payload
      .then(function(response) {
        // create a new action with the old type, but
        // replace the promise with the reponse data
        const newAction = { ...action, payload: response };
        dispatch(newAction);
      });
  }
}