I've been through many examples to understand how Redux-Thunk works and most the time the store is configured in a various way. I guess there's the old way or the new way but I'm kind of lost. Here is three pattern that I've identified. If someone can explain me the differences between them :
The simple way :
import { createStore, applyMiddleware } from 'redux';
import thunkMiddleware from 'redux-thunk'
import createLogger from 'redux-logger'
const loggerMiddleware = createLogger()
const store = createStore(rootReducer, applyMiddleware( thunkMiddleware, loggerMiddleware));
import { createStore, applyMiddleware } from 'redux'
import thunkMiddleware from 'redux-thunk'
import createLogger from 'redux-logger'
const loggerMiddleware = createLogger()
export default function configureStore(preloadedState) {
return createStore(
rootReducer,
preloadedState,
applyMiddleware(
thunkMiddleware,
loggerMiddleware
)
)
}
import {compose, createStore, applyMiddleware } from 'redux';
import thunkMiddleware from 'redux-thunk';
const createAppStore = compose(
applyMiddleware(thunkMiddleware)
)(createStore);
export default function configureStore(initialState){
const store = createAppStore(rootReducer, initialState);
return store;
};
import ReduxThunk from
'redux-thunk'
import thunkMiddleware from 'redux-thunk'
preloadedState
The signature for createStore is createStore(reducer, [preloadedState], [enhancer])
.
preloadedState
is an initial state you load before you initialize your app. For instance, if you prerender your first page on a server and want to pass app state as a JSON inside your HTML. Sometimes you need to fetch this state asynchronously that is where the second example is useful. You fetch your state and create a store using that state in the callback of your ajax call.
The third argument.
enhancer
is a higher-order function that composes a store creator to return a new, enhanced store creator. applyMiddleware
is a store enhancer
shipped with redux. If you want to combine multiple store enhancers you need to use compose
function.
For instance, redux-devtools-extension for chrome is an enhancer
so to use it in your app you would need compose
function
let store = createStore(reducer, initialState, compose(
applyMiddleware(...middleware),
window.devToolsExtension ? window.devToolsExtension() : f => f
));
When you import something from 'redux-thunk'
you use default export
so you can name your variable as you want. It doesn't matter.
A simple way is also correct if you don't need anything fancy it would work just fine.