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Reactjs useEffect does not change state value when fetching data

I'm trying to implement a Protected Route, which firstly tries to get an authentification(api call) so it can display the Route.
But somehow the state value doesnt change..
Do you got any idea?
const ProtectedRoute = ({ component: Component, ...rest }) => {
const [isAuthenticated, setIsAuthenticated] = useState(false);
const fetch = async () => {
const result = await axios.get("http://localhost:5000/auth/", {
withCredentials: true,
});
if (result.status >= 200 && result.status < 300) {
setIsAuthenticated(true);
} else {
setIsAuthenticated(false);
}
};
useEffect(() => {
fetch();
}, []);
return (
<Route
{...rest}
render={(props) => {
if (isAuthenticated) {
return <Component {...props} />;
} else {
return <Redirect to={"./loginUser"} />;
}
}}
/>
);
};
export default ProtectedRoute;

What you can do is to return something when the api call is still loading. Something like this :
const ProtectedRoute = ({ component: Component, ...rest }) => {
const [isAuthenticated, setIsAuthenticated] = useState(undefined);
const [isLoading, setIsLoading] = useState(false);
const fetch = async () => {
const result = await axios.get("http://localhost:5000/auth/", {
withCredentials: true,
});
if (result.status >= 200 && result.status < 300) {
setIsAuthenticated(true);
} else {
setIsAuthenticated(false);
}
};
useEffect(() => {
setIsLoading(true);
fetch();
setIsLoading(false);
}, []);
return (
<Route
{...rest}
render={(props) => {
if(isLoading) { // do something }
else if (isAuthenticated !== undefined && !isLoading) {
return <Component {...props} />;
} else {
return <Redirect to={"./loginUser"} />;
}
}}
/>
);
};
export default ProtectedRoute;

Redux State Management with a Input field

Bit of a noob to redux but this appears to be quite a difficult question! I hope someone may be able to help me :)
I have build a page where you can input a search for different types of jobs. From this, it will make a get request to my DB and get all the info on this job. As this page is multi-levelled, I want to use redux to dispatch and pass the state throughout. This will help me pass my data on the job, e.g Data Analyst, through to each component so it can use the data and populate fields.
However, this was how my input field was originally setup:
export function SearchBarComp(props) {
const [isExpanded, setExpanded] = useState(false);
const [parentRef, isClickedOutside ] = useClickOutside();
const inputRef = useRef();
const [searchQuery, setSearchQuery] = useState("");
const [isLoading, setLoading] = useState(false);
const [jobPostings, setjobPostings] = useState([]);
const [noRoles, setNoRoles] = useState(false)
const isEmpty = !jobPostings || jobPostings.length === 0;
const changeHandler = (e) => {
//prevents defaulting, autocomplete
e.preventDefault();
if(e.target.value.trim() === '') setNoRoles(false);
setSearchQuery(e.target.value);
}
const expandedContainer = () => {
setExpanded(true);
}
//LINK THE BACKEND!
const prepareSearchQuery = (query) => {
//const url = `http://localhost:5000/api/role/title?title=${query}`;
const url = `http://localhost:5000/api/role/titlerole?title=${query}`;
//replaces bad query in the url
return encodeURI(url);
}
const searchRolePosition = async () => {
if(!searchQuery || searchQuery.trim() === "")
return;
setLoading(true);
setNoRoles(false);
const URL = prepareSearchQuery(searchQuery);
const response = await axios.get(URL).catch((err) => {
console.log(err);
});
if(response) {
console.log("Response", response.data);
if(response.data && response.data === 0)
setNoRoles(true);
setjobPostings(response.data);
}
setLoading(false);
}
useDebounce(searchQuery, 500, searchRolePosition)
const collapseContainer = () => {
setExpanded(false);
setSearchQuery("");
setLoading(false);
setNoRoles(false);
if (inputRef.current) inputRef.current.value = "";
};
// console.log("Value", searchQuery)
useEffect(()=> {
if(isClickedOutside)
collapseContainer();
}, [isClickedOutside])
return (
<SearchBarContainer animate = {isExpanded ? "expanded" : "collapsed"}
variants={containerVariants} transition={containerTransition} ref={parentRef}>
<SearchInputContainer>
<SearchIconSpan>
<SearchIcon/>
</SearchIconSpan>
<SearchInput placeholder = "Search for Roles"
onFocus={expandedContainer}
ref={inputRef}
value={searchQuery}
onChange={changeHandler}
/>
<AnimatePresence>
{isExpanded && (<CloseIconSpan key="close-icon"
inital={{opacity:0, rotate: 0}}
animate={{opacity:1, rotate: 180}}
exit={{opacity:0, rotate: 0}}
transition={{duration: 0.2}}
onClick={collapseContainer}>
<CloseIcon/>
</CloseIconSpan>
)}
</AnimatePresence>
</SearchInputContainer>
{isExpanded && <LineSeperator/>}
{isExpanded && <SearchContent>
{!isLoading && isEmpty && !noRoles && (
<Typography color="gray" display="flex" flex="0.2" alignSelf="center" justifySelf="center">
Start typing to search
</Typography>
)}
{!isLoading && !isEmpty && <>
{jobPostings.map((searchRolePosition) => (
<JobSection
title={searchRolePosition.title}
//will need to do something like ----
//people = {searchRolePosition.title && searchRolePosition.title.average}
// future implementations
/>
))}
</>}
</SearchContent>}
</SearchBarContainer>
)
}
As you can see, the main thing is the 'query' this creates a backend request to my titlerole, such as getting the data on Data Analyst. This all works in my frontend right now, but I can't pass that data down to the next component etc
So i'm looking to use redux.
I've created the following slice:
import { createSlice } from "#reduxjs/toolkit";
const jobSearchSlice = createSlice({
name: "jobsearch",
initialState: {
currentRole: null,
isFetching: false,
error: false,
},
reducers: {
jobsearchStart: (state) => {
state.isFetching = true;
},
jobsearchSuccess: (state, action) => {
state.isFetching = false;
state.currentRole = action.payload;
},
jobsearchFailure: (state) => {
state.isFetching = false;
state.error = true;
},
},
});
export const { jobsearchStart, jobsearchSuccess, jobsearchFailure } = jobSearchSlice.actions;
export default jobSearchSlice.reducer;
With this, I'm also using the following apiCalls.js file:
import { jobsearchStart, jobsearchSuccess, jobsearchFailure } from "./jobsearchSlice";
import { publicRequest } from "../requestMethods";
export const roleSearchQuery = async (dispatch, jobsearch) => {
dispatch(jobsearchStart());
try{
const res = await publicRequest.get("`http://localhost:5000/api/role/titlerole?title=${query}`", jobsearch);
dispatch(jobsearchSuccess(res.data))
}catch(err){
dispatch(jobsearchFailure());
}
};
My question is as a Redux noob, how do I implement this query functionality into a redux API request? What's the way to do this properly as I begin to tranisition this to an app which uses standard state management!

How to wait until context value is set?

I'm trying to render a header.
First, in InnerList.js, I make an API call, and with the data from the API call, I set a list in context.
Second, in Context.js, I take the list and set it to a specific data.
Then, in InnerListHeader.js, I use the specific data to render within the header.
Problem: I currently get a TypeError undefined because the context is not set before rendering. Is there a way to wait via async or something else for the data to set before loading?
My code block is below. I've been looking through a lot of questions on StackOverflow and blogs but to no avail. Thank you!
InnerList.js
componentDidMount() {
const { dtc_id } = this.props.match.params;
const {
setSpecificDtcCommentList,
} = this.context;
MechApiService.getSpecificDtcCommentList(dtc_id)
.then(res =>
setSpecificDtcCommentList(res)
)
}
renderSpecificDtcCommentListHeader() {
const { specificDtc = [] } = this.context;
return (
<InnerDtcCommentListItemHeader key={specificDtc.id} specificDtc={specificDtc} />
)
}
Context.js
setSpecificDtcCommentList = (specificDtcCommentList) => {
this.setState({ specificDtcCommentList })
this.setSpecificDtc(specificDtcCommentList)
}
setSpecificDtc = (specificDtcCommentList) => {
this.setState({ specificDtc: specificDtcCommentList[0] })
}
InnerListHeader.js
render() {
const { specificDtc } = this.props;
return (
<div>
<div className="InnerDtcCommentListItemHeader__comment">
{specificDtc.dtc_id.dtc}
</div>
</div>
);
}

In general, you should always consider that a variable can reach the rendering stage without a proper value (e.g. unset). It is up to you prevent a crash on that.
For instance, you could rewrite you snippet as follows:
render() {
const { specificDtc } = this.props;
return (
<div>
<div className="InnerDtcCommentListItemHeader__comment">
{Boolean(specificDtc.dtc_id) && specificDtc.dtc_id.dtc}
</div>
</div>
);
}

When you make an api call you can set a loader while the data is being fetched from the api and once it is there you show the component that will render that data.
In your example you can add a new state that will pass the api call status to the children like that
render() {
const { specificDtc, fetchingData } = this.props;
if (fetchingData){
return <p>Loading</p>
}else{
return (
<div>
<div className="InnerDtcCommentListItemHeader__comment">
{specificDtc.dtc_id.dtc}
</div>
</div>
);
}
}
``

in my case, i am calling external api to firebase which lead to that context pass undefined for some values like user. so i have used loading set to wait untile the api request is finished and then return the provider
import { createContext, useContext, useEffect, useState } from 'react';
import {
createUserWithEmailAndPassword,
signInWithEmailAndPassword,
signOut,
onAuthStateChanged,
GoogleAuthProvider,
signInWithPopup,
updateProfile
} from 'firebase/auth';
import { auth } from '../firebase';
import { useNavigate } from 'react-router';
import { create_user_db, get_user_db } from 'api/UserAPI';
import { CircularProgress, LinearProgress } from '#mui/material';
import Loader from 'ui-component/Loader';
const UserContext = createContext();
export const AuthContextProvider = ({ children }) => {
const [user, setUser] = useState();
const [user_db, setUserDB] = useState();
const [isAuthenticated, setIsAuthenticated] = useState(false);
const [loading, setLoading] = useState(true);
const navigate = useNavigate();
const createUser = async (email, password) => {
const user = await createUserWithEmailAndPassword(auth, email, password);
};
const signIn = (email, password) => {
return signInWithEmailAndPassword(auth, email, password)
.then(() => setIsAuthenticated(true))
.catch(() => setIsAuthenticated(false));
};
const googleSignIn = async () => {
const provider = new GoogleAuthProvider();
await signInWithPopup(auth, provider)
.then(() => setIsAuthenticated(true))
.catch(() => setIsAuthenticated(false));
};
const logout = () => {
setUser();
return signOut(auth).then(() => {
window.location = '/login';
});
};
const updateUserProfile = async (obj) => {
await updateProfile(auth.currentUser, obj);
return updateUser(obj);
};
const updateUser = async (user) => {
return setUser((prevState) => {
return {
...prevState,
...user
};
});
};
useEffect(() => {
const unsubscribe = onAuthStateChanged(auth, async (currentUser) => {
setLoading(true);
if (currentUser) {
const user_db = await get_user_db({ access_token: currentUser.accessToken });
setUserDB(user_db);
setUser(currentUser);
setIsAuthenticated(true);
}
setLoading(false);
});
return () => {
unsubscribe();
};
}, []);
if (loading) return <Loader />;
return (
<UserContext.Provider value={{ createUser, user, user_db, isAuthenticated, logout, signIn, googleSignIn, updateUserProfile }}>
{children}
</UserContext.Provider>
);
};
export const UserAuth = () => {
return useContext(UserContext);
};

rewrite componentDidUpdate(prevProps) into a hook with redux

I would like to rewrite this life cycle method into a hook but it does'nt work as expected.
when the componentdidmounted, if the user id exists in the local storage,the user is connected and his name is displayed in the navbar. And when he disconnects and reconnects his name is displayed in the navbar.
So i am trying to convert this class Component with hooks, when the username changes nothing is displayed in the navbar so i have to refresh the page and that way his name is displayed
The real problem is the componentDidUpdate
how can i get and compare the prevProps with hooks
The class Component
const mapStateToProps = state => ({
...state.authReducer
}
);
const mapDispatchToProps = {
userSetId,
userProfilFetch,
userLogout
};
class App extends React.Component {
componentDidMount() {
const userId = window.localStorage.getItem("userId");
const {userSetId} = this.props;
if (userId) {
userSetId(userId)
}
}
componentDidUpdate(prevProps, prevState, snapshot) {
const {userId, userProfilFetch, userData} = this.props; //from redux store
if(prevProps.userId !== userId && userId !== null && userData === null){
userProfilFetch(userId);
}
}
render() {
return (
<div>
<Router>
<Routes/>
</Router>
</div>
);
}
}
export default connect(mapStateToProps,mapDispatchToProps)(App);
With hooks
const App = (props) => {
const dispatch = useDispatch();
const userData = useSelector(state => state.authReducer[props.userData]);
const userId = window.localStorage.getItem("userId");
useEffect(()=> {
if(!userId){
dispatch(userSetId(userId))
dispatch(userProfilFetch(userId))
}
}, [userData, userId, dispatch])
return(
<Router>
<Routes/>
</Router>
)
};
export default App;

How to get the previous props or state?
Basically create a custom hook to cache a value:
const usePrevious = value => {
const ref = useRef();
useEffect(() => {
ref.current = value;
});
return ref.current;
}
Usage:
const App = (props) => {
const dispatch = useDispatch();
const userData = useSelector(state => state.authReducer[props.userData]);
const userId = window.localStorage.getItem("userId");
// get previous id and cache current id
const prevUserId = usePrevious(userId);
useEffect(()=> {
if(!userId){
dispatch(userSetId(userId))
dispatch(userProfileFetch(userId))
}
// do comparison with previous and current id value
if (prevUserId !== userId) {
dispatch(userProfileFetch(userId));
}
}, [userData, userId, prevUserId, dispatch])
return(
<Router>
<Routes/>
</Router>
)
};
FYI: You may want to refactor the code a bit to do the fetch from local storage in an effect hook that runs only on mount. If I understand your app flow correctly it would look something like this:
const App = (props) => {
const dispatch = useDispatch();
const { userId } = useSelector(state => state.authReducer[props.userData]);
useEffect(() => {
const userId = window.localStorage.getItem("userId");
userId && dispatch(userSetId(userId));
}, []);
// get previous id and cache current id
const prevUserId = usePrevious(userId);
useEffect(()=> {
if(!userId){
dispatch(userSetId(userId))
dispatch(userProfileFetch(userId))
}
// do comparison with previous and current id value
if (prevUserId !== userId) {
dispatch(userProfileFetch(userId));
}
}, [userId, prevUserId, dispatch])
return(
<Router>
<Routes/>
</Router>
)
};

now i resolve it, i made this
const App = props => {
const userId = window.localStorage.getItem("userId");
const dispatch = useDispatch();
const userData = useSelector(state=> state.authReducer[props.userData]);
const isAuthenticated = useSelector(state=> state.authReducer.isAuthenticated);
useEffect(()=> {
if(userId){
dispatch(userSetId(userId))
dispatch(userProfilFetch(userId))
}
}, [userId])
return(
<div>
<Router>
<Routes/>
</Router>
</div>
)
};

Reducer is not saving data to state in React Context API

I am implementing authentication functionality in my app and when I try to save auth token which I get from my backend to reducer state it does nothing... I am new to this so there may be some dumb error.
This is my store.js file:
import React from 'react';
export const initialState = { access_token: null };
export const reducer = (state, action) => {
switch (action.type) {
case "SET_TOKEN":
console.log(action.data) // this does return the token which means data is passed correctly
return { access_token: action.data };
case "REMOVE_TOKEN":
return { access_token: null };
default:
return initialState;
}
};
export const Context = React.createContext();
This is my root component file AppRouter.js:
function AppRouter() {
const [store, dispatch] = useReducer(reducer, initialState);
const access_token = store.access_token;
console.log(access_token);
const AuthenticatedRoute = GuardedRoute(access_token);
return (
<Context.Provider value={{store, dispatch}}>
<Router>
<Switch>
<Route exact path="/" component={HomeScreen}/>
<Route exact path="/register" component={RegisterScreen}/>
<Route exact path="/login" component={LoginScreen}/>
<AuthenticatedRoute component={DashboardScreen} exact path={"/dashboard"}/>
</Switch>
</Router>
</Context.Provider>
)
}
So to me all this looks fine, and then this is the _login function in which I send the dispatch() to save the token(EDIT: this is everything between start of component function and return():
const [afterSuccessRegister, setAfterSuccessRegister] = useState(false);
const [emailInput, setEmailInput] = useState("");
const [passwordInput, setPasswordInput] = useState("");
const [loginErrorMessage, setLoginErrorMessage] = useState("");
const [createdUserEmail, setCreatedUserEmail] = useState("");
const { store, dispatch } = useContext(Context);
const _login = () => {
axios.post(`${ROOT_API}/v1/users/login`, {
"user": {
"email": emailInput,
"password": passwordInput
}
}, {}).then(res => {
console.log(res.data);
dispatch({type: 'SET_TOKEN', data: res.data.meta.access_token});
}).catch(err => {
console.log(err.response);
setLoginErrorMessage(err.response.data.message)
})
};
const _handleEmailChange = (e) => {
setEmailInput(e.target.value);
};
const _handlePasswordChange = (e) => {
setPasswordInput(e.target.value);
};
useEffect(() => {
if(typeof props.location.state !== "undefined") {
if (typeof props.location.state.success_register === 'undefined' || props.location.state.success_register === null || props.location.state.success_register === false) {
console.log("login");
} else {
setAfterSuccessRegister(true);
setCreatedUserEmail(props.location.state.created_user_email);
delete props.location.state;
}
}
}, [props.location.state]);
I really don't know why is it not saving it even though data is passed correctly. I tried adding console.log(store.access_token) after my login request has finished to see if it was saved, but it returns null.
Thanks!