React redux not updating global state

Question

I am using Redux without hooks and all seem to be tied together perfectly, but when I look in the browser console Redux window my state doesn't change. So basically I have a store file which looks like this

import {createStore, applyMiddleware} from "redux";

import thunk from 'redux-thunk'
import {composeWithDevTools} from "redux-devtools-extension/developmentOnly";
import rootReducer from './reducers'

const middleware = [thunk]
const initialState = {}

const store = createStore(rootReducer, initialState,composeWithDevTools(applyMiddleware(...middleware)))

export default store

then I have my global reducer file

import {combineReducers} from "redux";
import searchReducer from './searchReducer'

export default combineReducers({
    books: searchReducer
})

and the searchReducers file

import {SEARCH_BOOK, SET_INDEX,FETCH_BOOKS} from "../actions/types";

const initialState = {
    query: '',
    books: [],
    loading: false,
    book: []
}

export default function (state = initialState, action) {
    switch (action.type) {
        case 'SEARCH_BOOK':
            return {
                ...state,
                query:action.payload,
                loading: false
            }
        case 'SET_INDEX':
            return {
                ...state,
                index:action.payload,
                loading: false
            }
        case 'FETCH_BOOKS':
            return {
                ...state,
                index:state.index+40,
                books:state.books.concat(action.payload),
                loading: false
            }
        default:
            return state
    }
}

for now I only have the action type you see imported there here is that action

import {SEARCH_BOOK} from "./types";

export const searchBook = query => dispatch => {
    dispatch ({
        type:SEARCH_BOOK,
        payload:query
    })
}
export const fetchBooks = (query,index) => {
    console.log(query)
    axios
        .get(`https://www.googleapis.com/books/v1/volumes?q=${query}&maxResults=40&orderBy=relevance&startIndex=${index}`)
        .then(response =>{
            return({
                type: FETCH_BOOKS,
                payload: response.data.items
            })}
        )
        .catch(err => console.log(err));
};

All is tied together in the App where I imported the provider that wraps up everything. Here comes the problem. I have a search form that should on change update the query value of the global state

import React, { useState, useReducer} from "react";
import {useSelector, useDispatch} from 'react-redux'
import { Button, Container, Row, Col, Form, FormGroup, FormInput  } from "shards-react";
import queryBuilder from "../js/helper";
import style from "./SearchForm/body.module.css";
import {searchBook, fetchBooks} from "../actions/SearchActions";

const initialState = {
    title:'',
    author:'',
    publisher:''
}

function reducer(state,{ field, value }){
    return {
        ...state,
        [field]: value
    }
}
function SearchForm() {
    const index = useSelector(state => state.index)
    const [state, dispatch] = useReducer(reducer, initialState);
    const [query, setQuery] = useState('');
    const disp = useDispatch();

    const onChange = e => {
        dispatch({ field: e.target.name, value: e.target.value })
    }

    const { title,author,publisher } = state;
    const handleSubmit = e => {
        e.preventDefault()
        setQuery(queryBuilder(state))

        disp(fetchBooks(query, 0))
    }
    return(
        <div>
            <Container className={style.FormContainer}>

                <Form onSubmit={handleSubmit}>
                    <Row className={'topBar'}>
                        <Col>
                            <FormGroup>
                                <FormInput id={'bookTitle'} name={'title'}   placeholder={'title'} value={title} onChange={onChange}/>
                            </FormGroup>
                        </Col>
                        <Col>
                            <FormGroup>
                                <FormInput id={'bookAuthor'} name={'author'} value={author} onChange={onChange} placeholder={'author'}/>
                            </FormGroup>
                        </Col>
                        <Col>
                            <FormGroup>
                                <FormInput id={'bookPublisher'} name={'publisher'} value={publisher} onChange={onChange}
                                           placeholder={'publisher'}/>
                            </FormGroup>
                        </Col>
                        <Col>
                            <Button outline theme='primary' type={'submit'}>Submit</Button>
                        </Col>
                    </Row>

                </Form>
            </Container>
        </div>
    )
}

export default SearchForm

I don't know what is missing.

Edit As suggested I tried using hooks and now everything is tied together just fine. The problem is now with the fetching of the books. I updated the action file so you can see the action I added. When I dispatch this action I get this error

Actions must be plain objects. Use custom middleware for async actions

Does anybody know how to fix this?

Answer 1

I guess your error can be resolved as

export const fetchBooks =(query,index) => dispatch => {
    console.log(query)
    axios
        .get(`https://www.googleapis.com/books/v1/volumes?q=${query}&maxResults=40&orderBy=relevance&startIndex=${index}`)
        .then(response =>{
            dispatch({
                type: FETCH_BOOKS,
                payload: response.data.items
            })}
        )
        .catch(err => console.log(err));
};

Answer 2

It looks like you're missing a return in your fetchBooks function. You're not returning the promise, which means that the thunk middleware isn't receiving the promise result.

export const fetchBooks = (query,index) => {
    console.log(query)
    return axios
        .get(`https://www.googleapis.com/books/v1/volumes?q=${query}&maxResults=40&orderBy=relevance&startIndex=${index}`)
        .then(response =>{
            return({
                type: FETCH_BOOKS,
                payload: response.data.items
            })}
        )
        .catch(err => console.log(err));
};