I have a project that uses React + Redux + Thunk and I am rather new to the stack. I have a scenario where I am fetching an array from an API call in my action/reducer, but it is not re-rendering in a component/container that is hooked up to the Store. The component does render the first time when I fire up the app, but at that point the array is undefined when logged to console.
I am trying to display the array's length, so this is always resulting in 0. With ReduxDevTools I see that the state of network_identities does populate correctly and is longer zero... Where am I going wrong?
Here is my sample action
///////////// Sample action /////////////
import axios from 'axios';
const url = '[email protected]';
const authorization = 'sample_auth';
export function fetchConnections() {
const params = {
headers: {
authorization,
},
};
return (dispatch) => {
// call returns an array of items
axios.get(`${url}/connection`, params)
.then((connections) => {
let shake_profiles = [];
let connected_profiles = [];
let entity_res;
// map through items to fetch the items data, and split into seperate arrays depending on 'status'
connections.data.forEach((value) => {
switch (value.status) {
case 'APPROVED': case 'UNAPPROVED':
{
axios.get(`${url}/entity/${value.entity_id_other}`, params)
.then((entity_data) => {
entity_res = entity_data.data;
// add status
entity_res.status = value.status;
// append to connected_profiles
connected_profiles.push(entity_res);
});
break;
}
case 'CONNECTED':
{
axios.get(`${url}/entity/${value.entity_id_other}`, params)
.then((entity_data) => {
entity_res = entity_data.data;
entity_res.status = value.status;
shake_profiles.push(entity_res);
})
.catch(err => console.log('err fetching entity info: ', err));
break;
}
// if neither case do nothing
default: break;
}
});
dispatch({
type: 'FETCH_CONNECTIONS',
payload: { shake_profiles, connected_profiles },
});
});
};
}
Sample Reducer
///////////// Sample reducer /////////////
const initialState = {
fetched: false,
error: null,
connections: [],
sortType: 'first_name',
filterType: 'ALL',
shake_identities: [],
network_identities: [],
};
const connectionsReducer = (state = initialState, action) => {
switch (action.type) {
case 'FETCH_CONNECTIONS':
console.log('[connections REDUCER] shake_profiles: ', action.payload.shake_profiles);
console.log('[connections REDUCER] connected_profiles: ', action.payload.connected_profiles);
return { ...state,
fetched: true,
shake_identities: action.payload.shake_profiles,
network_identities: action.payload.connected_profiles,
};
default:
return state;
}
};
export default connectionsReducer;
Sample Store
///////////// Sample Store /////////////
import { applyMiddleware, createStore, compose } from 'redux';
import thunk from 'redux-thunk';
import promise from 'redux-promise-middleware';
import reducers from './reducers';
const middleware = applyMiddleware(promise(), thunk);
// Redux Dev Tools
const composeEnhancers = window.__REDUX_DEVTOOLS_EXTENSION_COMPOSE__ || compose;
const store = createStore(reducers, composeEnhancers(middleware));
export default store;
Sample Component - see if the API is done fetching the array, then display the length of the array
///////////// Sample Component /////////////
import React, { Component } from 'react';
import { connect } from 'react-redux';
import { Link } from 'react-router-dom';
import { bindActionCreators } from 'redux';
import CSSModules from 'react-css-modules';
import * as ConnectionActions from 'actions/connections';
import styles from './styles.scss';
function mapStateToProps(state) {
return {
network_identities: state.connections.network_identities,
loadedConnections: state.connections.fetched,
};
}
function mapDispatchToProps(dispatch) {
return {
actions: bindActionCreators(Object.assign({}, ConnectionActions), dispatch),
};
}
class Counter extends Component {
componentWillMount() {
const { network_identities, actions } = this.props;
if (!network_identities.length) {
console.log('||| fetching Connections');
actions.fetchConnections();
}
}
render() {
let { network_identities, loadedConnections} = this.props;
console.log('[Counter] network_identities[0]: ', network_identities[0]);
console.log('[Counter] network_identities: ', network_identities);
console.log('[Counter] loadingConnections: ', loadingConnections);
return (
<div>
<Link to="/network">
<div>
<span>Connections</span>
{ !loadedConnections ? (
<span><i className="fa fa-refresh fa-spin" /></span>
) : (
<span>{network_identities.length}</span>
) }
</div>
</Link>
</div>
);
}
}
export default connect(mapStateToProps, mapDispatchToProps)(CSSModules(Counter, styles));
I suspect I am either mutating the state in my reducer, or I am misusing Thunk.
connections.data.forEachis sketchy, as it won't wait until the fetches have completed. The fetches will mutate the state afterwards, but won't trigger a rerender because dispatch has already fired. Might be better to map theconnectionsto promises and wait for the results with.all().