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Why is my function not dispatching in react component?

why is fetchReviews not fetching?
Originally didn't use fetchData in use effect.
Ive tried using useDispatch.
BusinessId is being passed into the star component.
no errors in console.
please let me know if theres other files you need to see.
thank you!
star component:
import React, { useState, useEffect } from 'react';
import { useDispatch } from 'react-redux';
import {AiFillStar } from "react-icons/ai";
import { fetchReviews } from '../../actions/review_actions';
function Star(props) {
const [rating, setRating] = useState(null);
// const [reviews, setReview] = useState(props.reviews)
// const dispatch = useDispatch();
useEffect(() => {
const fetchData = async () => {
await fetchReviews(props.businessId)
};
fetchData();
console.log(props);
// getAverageRating();
});
const getAverageRating = () => {
let totalStars = 0;
props.reviews.forEach(review => {totalStars += review.rating});
let averageStars = Math.ceil(totalStars / props.reviews.length);
setRating(averageStars);
}
return (
<div className='star-rating-container'>
{Array(5).fill().map((_, i) => {
const ratingValue = i + 1;
return (
<div className='each-star' key={ratingValue}>
<AiFillStar
className='star'
color={ratingValue <= rating ? '#D32322' : '#E4E5E9'}
size={24} />
</div>
)
})}
</div>
);
};
export default Star;
star_container:
import { connect } from "react-redux";
import { withRouter } from "react-router-dom";
import Star from "./star";
import { fetchReviews } from "../../actions/review_actions";
const mSTP = state => {
return {
reviews: Object.values(state.entities.reviews)
};
}
const mDTP = dispatch => {
return {
fetchReviews: businessId => dispatch(fetchReviews(businessId))
};
};
export default connect(mSTP, mDTP)(Star);
console image
why is fetchReviews not fetching? Originally didn't use fetchData in use effect. Ive tried using useDispatch. BusinessId is being passed into the star component. no errors in console.
edit!***
made some changes and added useDispatch. now it wont stop running. its constantly fetching.
function Star(props) {
const [rating, setRating] = useState(null);
const [reviews, setReview] = useState(null)
const dispatch = useDispatch();
useEffect(() => {
const fetchData = async () => {
const data = await dispatch(fetchReviews(props.businessId))
setReview(data);
};
fetchData();
// console.log(props);
// getAverageRating();
}), [];

ended up just calling using the ajax call in the useEffect.
useEffect(() => {
const fetchReviews = (businessId) =>
$.ajax({
method: "GET",
url: `/api/businesses/${businessId}/reviews`,
});
fetchReviews(props.businessId).then((reviews) => getAverageRating(reviews));
}), [];
if anyone knows how i can clean up and use the dispatch lmk.
ty all.

useEffect(() => {
const fetchData = async () => {
const data = await dispatch(fetchReviews(props.businessId))
setReview(data);
};
fetchData();
// console.log(props);
// getAverageRating();
}), [];
dependency array is outside the useEffect. Since useEffect has no dependency option passed, function inside useEffect will run in every render and in each render you keep dispatching action which changes the store which rerenders the component since it rerenders code inside useEffect runs
// pass the dependency array in correct place
useEffect(() => {
const fetchData = async () => {
const data = await dispatch(fetchReviews(props.businessId))
setReview(data);
};
fetchData();
// console.log(props);
// getAverageRating();
},[]), ;
Passing empty array [] means, code inside useEffect will run only once before your component mounted

useEffect keeps rendering

In a react app, when creating a component, I use useEffect to handle a HTTP request via a custom hook (which fetch via a useCallback). Then, to parse the parameters for the request, I have a layer for services which return the expected values.
As a result, this workflow keeps re-rendering in a loop and the apps gets stacked.
Component:
import React, { Fragment, useContext, useEffect, useState } from 'react';
import { NavLink } from 'react-router-dom';
import { useParams } from 'react-router-dom';
import { useTranslation } from 'react-i18next';
import { getProject } from '../../../services/Project.service';
import { AuthContext } from '../../../shared/context/auth.context';
import { NavOptions } from '../../../shared/constants/NavOptions';
import { useHttpClient } from '../../../shared/hooks/http.hook';
import SideNavigation from '../../../shared/components/Navigation/SideNavigation/SideNavigation';
import NavLinks from '../../../shared/components/Navigation/NavLinks/NavLinks';
import './Dashboard.css';
const Dashboard = (props) => {
console.log('Dashboard...');
const { isLoading, error, sendRequest, clearError } = useHttpClient();
const [project, setProject] = useState();
const auth = useContext(AuthContext);
const projectId = useParams().projectId;
const getProject = async () => {
console.log('getProject...');
console.log('auth', auth.token);
const response = await sendRequest(getProject(projectId, auth.token));
if (response.status === 201) {
const responseData = await response.json();
console.log('project:', responseData);
setProject(responseData);
} else {
console.log('getting buildings failed!');
const error = await response.json();
}
};
useEffect(() => {
projectId && getProject();
}, []);
const { t, i18n } = useTranslation();
let content = (
<div className="bim-y-dashboard">
.
.
.
</div>
);
return (
<Fragment>
<SideNavigation>
<NavLinks options={NavOptions.PROJECT} projectId />
</SideNavigation>
<MainContent>{content}</MainContent>
</Fragment>
);
};
export default Dashboard;
Custom hook:
export const useHttpClient = () => {
const auth = useContext(AuthContext);
const [isLoading, setIsLoading] = useState(false);
const [error, setError] = useState();
const activeHttpRequests = useRef([]);
const sendRequest = useCallback(
async (url, method = 'GET', body = null, headers = {}) => {
console.log('sendRequest...');
console.log('url', url);
console.log('method', method);
console.log('body', body);
console.log('headers', headers);
},[]);
const clearError = () => {
setError(null);
};
useEffect(() => {
return () => {
activeHttpRequests.current.forEach(abortCtrl => abortCtrl.abort());
};
}, []);
return { isLoading, error, sendRequest, clearError };
};
Service:
export const getProject = (projectId, token) => {
console.log('getProject...');
return (`/projects/id/${projectId}`, 'GET', null, {
'Content-Type': 'application/json',
Authorization: 'Bearer ' + token,
});
}
What am I missing to avoid this constant re-rendering?
Thanks in advance.

I have the feeling your issue is in code you have not shared, as the above looks legit.
Things you can try:
Comment out const auth = useContext(AuthContext); in your custom hook to make sure the culprit is not in your context
Make sure const response = await sendRequest(..) returns what you are expecting
Add a new hook, something like const [data, setData] = useState(null), then after you get a response, set it in your hook setData(response)
Finally, in your useEffect, update your condition as projectId && !data && getProject();
That will ensure your re rendering issue is neither on your auth context nor in your fetch request.
Hope that helps; if not, please update the question with the full code of your component and I'll take a second look :)

RESOLVED:
Found this post: Link
It explains that because of sendRequest method, it keeps re-rendering.

Why does copies of the same API call returned undefined for one function and works for the other

While trying to use TMDB API in my project I ran into an issue that I am unable to figure out. I use copies of the same code as shown below in two different files and functions - one works, and the other one returned undefined for some reason. Can you please point out what I am not doing right, I need fresh new eyes on this. Thank you
import Head from 'next/head';
import React from 'react';
import { useState, useEffect } from 'react';
import Link from 'next/link';
import styles from '../styles/Home.module.css';
export const getServerSideProps = async () => {
const movieApi = process.env.TMDB_API_KEY;
const res = await fetch(`https://api.themoviedb.org/3/discover/movie?sort_by=popularity.desc&api_key=${movieApi}&page=1`);
const movie_data = await res.json();
return {
props: {
movies : movie_data
},
}
}
const Form = ({movies}) => {
console.log(movies); //returns "Undefined"
const [search, Setsearch] = useState("");
//Handle input value
const getLocation = async (e) => {
// console.log(e.target.value)
e.preventDefault();
}
//Handle Submit
const handleSubmit = (event) =>{
// console.log("clicked")
event.preventDefault();
}
export const getServerSideProps = async () => {
const movieApi = process.env.TMDB_API_KEY;
const res = await fetch(`https://api.themoviedb.org/3/discover/movie?sort_by=popularity.desc&api_key=${movieApi}&page=1`);
const movie_data = await res.json();
return {
props: {
movies : movie_data
},
}
}
export default function Home({movies}) {
console.log(movies); //works perdectly
const [session, loading] = useSession();
const tmdbMpviesResults = movies.results

As per your comment, <Form /> is not a page. Exactly that is your problem:
getServerSideProps can only be exported from a page. You can’t export it from non-page files.

ReactJS: Function run multiple times without being called

Is there any reason a function in a react component would run multiple times although it is being invoked only once?
I have this test function that auto-invokes itself as in:
let xfunction = (() =>
{
console.log('test');
}
)();
This is what I get in the console:
App.js Source Code:
import React, { useState, useEffect } from 'react';
import { getAllPokemons } from './services/pokemon'
import './App.css';
function App() {
const [pokemonData, setPokemonData] = useState([]);
const [loading, setLoading] = useState(true);
const initialUrl = 'payload.json'
useEffect(() => {
async function fetchData() {
let response = await getAllPokemons(initialUrl);
console.log(response);
await loadingPokemon(response.pokemon);
setLoading(false);
}
fetchData();
}, [])
const loadingPokemon = async (data) => {
let _pokemon = await Promise.all(data.map(async pokemon => {
return pokemon;
})
);
setPokemonData(_pokemon);
}
// Start - Filter by Pokemon Type
let pokemonTypes = (() =>
{
console.log('test');
}
)();
// End - Filter by Pokemon Type
return (
<div></div>
);
}
export default App;
The function is not being called or references anywhere else!
Thanks!

Solution as proposed by #Jared Smith:
If you do not want your functions rerendered and you are using react hooks, please include them in the useEffect hook as in:
useEffect(() => {
async function fetchData() {
let response = await getAllPokemons(initialUrl);
await loadingPokemon(response.pokemon);
setLoading(false);
}
fetchData();
includeFunctionHere();
}, [])

How to fire the function useEffect after clicking event?

Recently am learning React hooks and am now doing a search app which have to call API then return the list movies correspond to what i type in the search box.
My code here:
useFetch.js
import { useState, useEffect } from 'react'
export const useFetch = (url, initialState) => {
const [data, setData] = useState(initialState)
const [loading, setLoading] = useState(true)
useEffect(() => {
async function fetchMovies() {
const response = await fetch(url)
const data = await response.json()
setData(data.Search)
setLoading(false)
}
fetchMovies()
}, [url])
return { data, loading }
}
App.js
import React, { useState } from 'react'
import Search from './components/Search'
import Result from './components/Result'
import Loading from './components/Loading'
import { useFetch } from './utils/useFetch'
export default function App() {
const [key, setKey] = useState('Iron man')
const onSearch = (key) => {
setKey(key)
}
const {data, loading} = useFetch(`https://www.omdbapi.com/?s=${key}&apikey=${API_KEY}`)
return (
<>
<Search handleSearch={onSearch}/>
<Loading isLoading={loading} />
<Result movies={data}/>
</>
)
}
As far as i understand after clicking button search function call API will be fired and return the result as expect. I can't put
const {data, loading} = useFetch(`https://www.omdbapi.com/?s=${key}&apikey=${API_KEY}`)
inside onSearch function. Follow the code function call API is automatically called whenever the app start and return undefined as result.
Can anyone help me out and explain why?

You are correct in your understanding of how hooks can only be called at the top level in a react component. Make the following changes and the API won't get called the first time around but will get called subsequently.
Use url state variable and extract generateUrl logic outside the component:
function generateUrl(key) {
return `https://www.omdbapi.com/?s=${key}&apikey=${API_KEY}`
}
function MyComponent() {
const [url, setUrl] = React.useState('');
//...
}
Check for url presence in useFetch hook by wrapping fetchMovies() call in an if condition. This way, API won't trigger since default value of url is empty.
import { useState, useEffect } from 'react'
export const useFetch = (url, initialState) => {
const [data, setData] = useState(initialState)
const [loading, setLoading] = useState(true)
useEffect(() => {
async function fetchMovies() {
const response = await fetch(url)
const data = await response.json()
setData(data.Search)
setLoading(false)
}
if(url) {
fetchMovies()
}
}, [url])
return { data, loading }
}
Finally, modify onSearch
const onSearch = (key) => {
setUrl(generateUrl(key))
}

Perhaps you could expose setUrl through something like:
return { data, loading, onSearch: (key) => setUrl(generateUrl(key)) }