👀 Views: 94 💬 Answers: 1 📅 Created: 2025-06-11

node.js async-await mongodb express JavaScript

Could someone explain I'm converting an old project and I recently switched to I'm working on a project and hit a roadblock... I'm working with an scenario with race conditions in my Node.js API where I need to fetch user data and their related posts simultaneously. I'm using async/await and I've noticed that sometimes the user data returns before the posts, leading to incorrect data being sent back in the response. Here's a simplified version of what my code looks like: ```javascript const express = require('express'); const app = express(); const { getUser, getPostsByUserId } = require('./dataService'); app.get('/user/:id', async (req, res) => { try { const userId = req.params.id; const user = await getUser(userId); const posts = await getPostsByUserId(userId); res.json({ user, posts }); } catch (behavior) { console.behavior('behavior fetching user data:', behavior); res.status(500).send('Internal Server behavior'); } }); app.listen(3000, () => { console.log('Server running on http://localhost:3000'); }); ``` In my `dataService.js`, both `getUser` and `getPostsByUserId` are making calls to a MongoDB database using Mongoose: ```javascript async function getUser(userId) { return await User.findById(userId); } async function getPostsByUserId(userId) { return await Post.find({ userId }); } ``` I sometimes get responses where the `posts` array is empty although the user exists. I've tried adding console logs to see the order of execution, and while it appears that both await calls are executed in sequence, the posts can occasionally be fetched before the user data is fully resolved. Is there a way to ensure that the results are always returned in the correct order or any way to handle this race condition? I'm using Node.js v14 and Mongoose v5.11.15. Any insights would be appreciated! I'm coming from a different tech stack and learning Javascript. This is happening in both development and production on Linux. Thanks in advance! I've been using Javascript for about a year now. Thanks in advance! I'd love to hear your thoughts on this. Am I approaching this the right way?