15

I am looking at thunk and trying to figure out how to implement an api call. It is not working so I have gone back to the very basics. When I click on the button it shows 'Getting here! in the console, but nothing is showing when I console.log(dispatch). Am I missing something here?

import React from 'react';
import ReactDOM from 'react-dom';
import { createStore, applyMiddleware } from 'redux';
import { connect, Provider } from 'react-redux';
import thunk from 'redux-thunk' 
import axios from 'axis';

const store = createStore(
    reducer,
    applyMiddleware(thunk)
);

function fetchUser() {
    return axios.get('https://randomuser.me/api/');
}

function addUser() {
    console.log('Getting here');
    return (dispatch) => {
        console.log(dispatch) //not showing anything
        return fetchUser().then(function(data){
          console.log(data);
        });
    };
}

class App extends React.Component {
    addUser() {
        addUser();
    }

    render() {
        return (
           <button onClick={this.addUser.bind(this)}>+</button>
        )       
    }
}

const mapPropsToState = function(store){
    return {
        newState: store
    }
}

var ConnectApp = connect(mapPropsToState)(App);

ReactDOM.render(
    <Provider store={store}>
        <ConnectApp />
    </Provider>,
    document.getElementById('app')
)

3 Answers3

19

You cannot call addUser() from your component as a regular function. You have to use a mapDispatchToProps function and pass it to your connect call in order to be able to dispatch addUser().

const mapDispatchToProps = dispatch => ({addUser: () => dispatch(addUser())})

then 

ConnectApp = connect(mapPropsToState, mapDispatchToProps)(App);

Now you can call it as a prop.

addUser() {
        this.props.addUser();
    }
Rami Enbashi
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4

You're not actually dispatching the thunk. You're calling it directly. You need to pass the inner () => {} thunk function to dispatch.

There's several ways to handle this. Since you're not providing a mapDispatchToProps argument to connect, the App component will automatically be given this.props.dispatch(). So, in App.addUser(), you could do this.props.dispatch(addUser()).

Another way would be to pre-bind the addUser action creator. You could do this with the syntax var ConnectApp = connect(mapPropsToState, {addUser})(App). Then, when you call this.props.addUser(), it will automatically dispatch the result.

I have some discussion on use of action creators and binding at http://blog.isquaredsoftware.com/2016/10/idiomatic-redux-why-use-action-creators/ , and a couple gists with sample code for binding and dispatching at https://gist.github.com/markerikson/6c7608eee5d2421966d3df5edbb8f05c and https://gist.github.com/markerikson/f46688603e3842af0f9720dea05b1a9e .

markerikson
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0

If you do not want to use connect function then you can use useDispatch() hook.

const dispatch = useDispatch();

 useEffect(() => {
    dispatch(addUser())
 }, [])

You can use componentDidMount or UseEffect to fetch data.

Amit Bishnoi
  • 1