👀 Views: 91 💬 Answers: 1 📅 Created: 2025-06-12

react express async-await JavaScript

I've searched everywhere and can't find a clear answer. After trying multiple solutions online, I still can't figure this out. I'm working on a React application where I fetch data from an Express API. The API returns a list of users, and I want to set this data into the component's state. However, I'm working with an scenario where the fetched data is 'undefined' when I try to access it. I'm using the latest version of React (v18.0.0) and Express (v4.17.1). Here's the relevant code snippet: ```javascript // fetchUsers.js - a simple API call using fetch export const fetchUsers = async () => { const response = await fetch('http://localhost:5000/api/users'); const data = await response.json(); return data; }; ``` In my component, I'm calling this function inside a useEffect: ```javascript import React, { useEffect, useState } from 'react'; import { fetchUsers } from './fetchUsers'; const UserList = () => { const [users, setUsers] = useState([]); const [loading, setLoading] = useState(true); useEffect(() => { const loadUsers = async () => { try { const data = await fetchUsers(); console.log('Fetched data:', data); // This logs 'undefined' setUsers(data); } catch (behavior) { console.behavior('behavior fetching users:', behavior); } finally { setLoading(false); } }; loadUsers(); }, []); if (loading) return <div>Loading...</div>; return ( <ul> {users.map(user => <li key={user.id}>{user.name}</li>)} </ul> ); }; export default UserList; ``` When I log the `data` variable inside the `loadUsers` function, it shows `undefined`. The API endpoint seems to be correct, and I can confirm that it returns the expected JSON response when tested with Postman. I've checked the network tab in the browser's dev tools, and the response is coming back fine, but for some reason, it's not being set correctly in my component. I've tried adding behavior handling and verifying the response status before parsing it, but the question continues. Is there something I might be overlooking or a common pitfall when working with async functions in React? Any insights would be greatly appreciated! I'm working on a web app that needs to handle this. Am I missing something obvious? I'd really appreciate any guidance on this. For reference, this is a production web app. Thanks, I really appreciate it!