How to send data from React to Express - node.js

Question

I'm trying to create login/registration for an app using React/Node/Express/Postgres. Where I'm getting stuck is receiving data on the server side from my form in React.
I have a register component for the form in register.js
import React from 'react';
import useForm from '../form/useForm';
const Register = () => {
const { values, handleChange, handleSubmit } = useForm({
name: '',
email: '',
password: "",
password2: ""
}, register);
function register() {
console.log(values);
}
return (
<div className="row mt-5">
<div className="col-md-6 m-auto">
<div className="card card-body">
<h1 className="text-center mb-3">
<i className="fas fa-user-plus"></i> Register
</h1>
<form
action="/users/register"
method="POST"
onSubmit={handleSubmit}>
<div className="form-group">
<label htmlFor="name">Name</label>
<input
className="form-control"
type="name"
name="name"
onChange={handleChange}
placeholder="Enter Name"
value={values.name}
required />
</div>
<div className="form-group">
<label htmlFor="email">Email</label>
<input
className="form-control"
type="email"
name="email"
onChange={handleChange}
placeholder="Enter Email"
value={values.email}
required />
</div>
<div className="form-group">
<label htmlFor="email">Password</label>
<input
className="form-control"
type="password"
name="password"
onChange={handleChange}
placeholder="Create Password"
value={values.password}
required />
</div>
<div className="form-group">
<label htmlFor="email">Confirm Password</label>
<input
className="form-control"
type="password"
name="password2"
onChange={handleChange}
placeholder="Confirm Password"
value={values.password2}
required />
</div>
<button type="submit" className="btn btn-primary btn-block">
Register
</button>
</form>
<p className="lead mt-4">Have An Account? Login</p>
</div>
</div>
</div>
);
};
export default Register;
A hook to handle the form actions in useForm.js
import {useState, useEffect} from 'react';
const useForm = (initialValues, callback) => {
const [hasError, setErrors] = useState(false);
const [values, setValues] = useState(initialValues);
const handleSubmit = (event) => {
if (event) event.preventDefault();
const options = {
method: "POST",
headers: {
"Content-Type": "application/json"
},
body: JSON.stringify(setValues(values => ({ ...values, [event.target.name]: event.target.value })))
}
fetch("/users/register", options)
}
const handleChange = (event) => {
event.persist();
setValues(values => ({ ...values, [event.target.name]: event.target.value }));
};
return {
handleChange,
handleSubmit,
values,
}
};
export default useForm;
Then I have a file to manage the routes for logging in/registering in users.js
const express = require("express");
const Router = require("express-promise-router");
const db = require("../db");
const router = new Router();
//Login page
router.get('/login', (req, res) => res.send("Login"));
//Register page
router.get('/register', (req, res) => res.send("Register"));
//Register Handle
router.post('/register', (req, res) => {
console.log(req.body);
res.send('hecks');
});
module.exports = router;
I have tried messing with things inside of the handleSubmit function in my useForm.js hook, but everything leads to the console.log(req.body) from my users.js file to return as undefined. Where am I going wrong?
Edit #1: Snip from Postman sending post request
Edit #2: basic project structure
.
./client
./client/src
./client/src/components
./client/src/components/register
./client/src/components/register/register.js
./client/src/components/form
./client/src/components/form/useForm.js
./client/src/App.js
./routes
./routes/index.js
./routes/users.js
./server.js
Edit #3: Main server.js file
const express = require("express");
const mountRoutes = require("./routes");
const app = express();
mountRoutes(app);
var bodyParser = require("body-parser");
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));
//catch all other routes
app.get("*", function(req, res) {
res.send("<h1>Page does not exist, sorry</h1>");
});
const port = process.env.PORT || 5000;
app.listen(port, () => console.log(`Server started on port ${port}`));

Answer 1

You’re setting state in JSON.stringify which returns undefined. you’ve to pass values in it:
const handleSubmit = (event) => {
if (event) event.preventDefault();
const options = {
method: "POST",
headers: {
"Content-Type": "application/json"
},
body: JSON.stringify(values)
}
fetch("/users/register", options)
}

Answer 2

You need to apply bodyParser before mounting routes.
So change like this:
var bodyParser = require("body-parser");
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));
mountRoutes(app);
You don't use then or await in the handleSubmit function which may cause problem.
Can you update the handleSubmit function like this and try?
const handleSubmit = async event => {
if (event) event.preventDefault();
const options = {
method: "POST",
headers: {
"Content-Type": "application/json"
},
body: JSON.stringify(values)
};
try {
const response = await fetch("/users/register", options);
const responseData = await response.json();
if (response.ok) {
console.log("response ok");
callback();
} else {
console.log("response NOT ok");
throw new Error(responseData.message);
}
} catch (err) {
console.log(err);
if (err.response) {
console.log(err.response.data);
}
}
};

Answer 3

👨‍🏫 You can try with this code below:
userForm.js: Make sure your handleSubmit in your userForm.js it's looks like this code below: 👇
const handleSubmit = async(event) => {
if (event) event.preventDefault();
const options = {
method: "POST",
headers: {
"Content-Type": "application/json"
},
body: JSON.stringify(values)
}
try {
// change with your endpoint
const endpoint = 'http://localhost:3001/users/register';
const result = await fetch(endpoint, options);
// send value to your register function
callback(result);
} catch (ex) {
console.log('Something failed');
console.log(ex);
}
}
You've to use callback(result), so you can console.log that value on your register function.
express server: Make sure in your express server, you've been add body-parser, it's will looks like this code below: 👇
app.use(express.json());
app.use(express.urlencoded({ extended: true }));
That code above will make your req.body works.
I hope it can help you 🙏.