I'm trying to fetch some backend data on my Express.js backend which looks like this:
const express = require('express')
const app = express()
app.get("/api", (req, res) => {
res.json({"data": ["data1", "data2", "data3"]})
})
app.listen(5000, () => { console.log("Server started on port 5000, hi") })
Every time the specific page loads I want it to fetch the {"data": ["data1", "data2", "data3"]} from the backend, I added a button that makes the same request for testing as well. Whenever I click the button and whenever the page loads I get this error:
I don't really understand why I'm getting this error, here is my next.js code:
import React, { Component, useEffect, useState } from 'react';
import axios from 'axios';
export default function Product() {
const [backendData, setBackendData] = useState([{}])
useEffect(() => {
axios.get('/api').then(
response => response.json()
).then(
data => {
setBackendData(data)
}
)
console.log("ran")
}, [])
const test = () => {
axios.get('/api').then(
response => response.json()
).then(
data => {
setBackendData(data)
}
)
console.log("test clicked")
}
return (
<div style={styles.container}>
<div style={styles.speechTitle}>Talk to us, tell us about your day...</div>
<div style={styles.speechBox}>
Test
</div>
<button onClick={console.log("start")}>
Start
</button>
<button onClick={console.log("stop")}>Stop</button>
<button onClick={console.log("reset")}>Reset</button>
{(typeof backendData.data === 'undefined') ? (
<p>Loading...</p>
) : (
backendData.data.map((data, i) => (
<p key={i}>{data}</p>
))
)}
<button onClick={() => test()}>asdasd</button>
</div>
);
}
I'm running this component called Product you see above in this file called product.js which is in my pages folder:
import React from 'react';
import { ThemeProvider } from 'theme-ui';
import { StickyProvider } from 'contexts/app/app.provider';
import theme from 'theme';
import SEO from 'components/seo';
import Layout from 'components/layout';
import Product from 'components/product-input'
export default function ProductPage() {
return (
<ThemeProvider theme={theme}>
<StickyProvider>
<Layout>
<SEO title="Talkhappi" />
<Product/>
</Layout>
</StickyProvider>
</ThemeProvider>
);
}
I am also getting a network error when I open up the network tab in developer tools:
I'm unsure how to fix this problem and retrieve the data I want to retrieve from my backend running at port 5000.

