Action does not trigger a reducer in Redux

Question

I'm new to redux and trying to fetch content using the Contentful API. For some reason the action I call does not reach the reducer. I have attached the code I feel is relevant and any contributions would be highly appreciated.

actions/index.js

import axios from 'axios';

const API_BASE_URL = 'https://cdn.contentful.com';
const API_SPACE_ID = 'xxxxxxxxxxxxx';
const API_KEY ='xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx';

const FETCH_CONTENT = 'fetch_content';

export function fetchContent() {
  const request = axios.get(`${API_BASE_URL}/spaces/${API_SPACE_ID}/environments/master/entries?access_token=${API_KEY}`);
  return {
    type: FETCH_CONTENT,
    payload: request
  };
  }

reducers/index.js

import { combineReducers } from 'redux';
import ContentReducer from './reducer-content';

const rootReducer = combineReducers({
  contents: ContentReducer
});

export default rootReducer;

reducer-content.js

import {FETCH_CONTENT} from '../actions';
const INITIAL_STATE = { all: [] };

export default function(state = INITIAL_STATE, action){
  switch(action.type){
    case FETCH_CONTENT:
      return { ...state, all: action.payload.data.items };

  default:
  return state;
  }
}

index.js

import React from 'react';
import ReactDOM from 'react-dom';
import { Provider } from 'react-redux';
import { createStore, applyMiddleware } from 'redux';
import { BrowserRouter, Route, Switch } from "react-router-dom";
import promise from 'redux-promise';
import { logger } from 'redux-logger'


import ContentIndex from './components/content-index';
import reducers from './reducers';

const createStoreWithMiddleware = applyMiddleware(promise, logger)(createStore);

ReactDOM.render(
  <Provider store={createStoreWithMiddleware(reducers)}>
    <BrowserRouter>
      <div>
      <Route  path = "/" component = {ContentIndex}/>
    </div>
    </BrowserRouter>

  </Provider>
  , document.querySelector('.container'));

components/content-index.js

import React, {Component} from 'react';
import {fetchContent} from '../actions';
import {connect} from 'react-redux';
import _ from 'lodash';

class ContentIndex extends Component {
  componentDidMount(){
    this.props.fetchContent();
  }

  renderContent(props){
    return this.props.contents.map((content, index) => {
      return (
        <article key={content.sys.id}>
          <h3>{content.fields.name}</h3>
          <p>{content.fields.website}</p>
        </article>
      );
    });
  }

  render(){
    return(
      <div>
      <h3>Content</h3>
      {this.renderContent()}
      </div>
    );
  }
}

const mapStateToProps = (state) => {
  return {contents: state.contents.all};
}
// export default CharacterIndex;
export default connect(mapStateToProps, {fetchContent})(ContentIndex);

Answer 1

You can simplify your code and avoid dispatching asynchronous actions and needing to use redux middleware by doing the following:

• Convert fetchContent() into an async function that returns an action with the items in the payload
• create a mapDispatchToProps that creates a function that dispatches the action returned by fetchContent()

fetchContent() would look like this:

export async function fetchContent() {
  const request = await axios.get(`${API_BASE_URL}/spaces/${API_SPACE_ID}/environments/master/entries?access_token=${API_KEY}`);
  return {
    type: FETCH_CONTENT,
    payload: request.data.items
  };
}

connect would look like this:

const mapStateToProps = (state) => {
  return {contents: state.contents.all};
}

const mapDispatchToProps = (dispatch) => {
  return {
    loadItems: () => fetchContent().then(action => dispatch(action))
  }
}

// export default CharacterIndex;
export default connect(mapStateToProps, mapDispatchToProps)(ContentIndex);

your reducer would look like this:

export default function(state = INITIAL_STATE, action){
  switch(action.type){
    case FETCH_CONTENT:
      return { ...state, all: action.payload };

  default:
  return state;
  }
}

and componentDidMount() would look like this:

  componentDidMount(){
    this.props.loadItems();
  }

Answer 2

Update

It seems that I'm wrong here (Thanks to @Dave Newton's comments). redux-promise waits a promise and if it receives one, resolves it and dispatches the value. So, using an async function and using an action creator here is useless.

---

You are using redux-promise, I don't know how it handles the situation but in its Github repo there is an example with redux-actions and it uses an async function. I'm more familiar with redux-thunk but probably it suits in your situation to use an async action creator here.

Try this:

export async function fetchContent() {
  const request = await axios.get(`${API_BASE_URL}/spaces/${API_SPACE_ID}/environments/master/entries?access_token=${API_KEY}`);
  return {
    type: FETCH_CONTENT,
    payload: request
  };
}

Answer 3

axios.get() returns promise.

So you need use async / await.