How do I use express.json() and set headers (res.setHeader) simultaneously? - json

Question

I am trying to view the body of a POST request and also set some headers. Specifically, I need to allow localhost -> localhost communication, which means adding Access-Control-Allow-Origin: * as a header.
My code so far is:
const express = require("express");
const app = express();
const port = 8080;
app.use(express.json());
app.use((req, res, next) => {
res.setHeader("Access-Control-Allow-Origin", "*");
res.header(
"Access-Control-Allow-Headers",
"Origin, X-Requested-With, Content-Type, Accept"
);
res.sendStatus(200);
next();
});
app.post('/', function (req, res) {
console.log(req.body.name)
res.end();
});
app.listen(port, () => console.log(`Listening on port ${port}`));
When I run the server I get Cannot set headers after they are sent to the client.
How can I combine both app.use()s?
I've tried changing the order of the calls but that doesn't work.

Answer 1

I figured out a way after I posted the question, so I'm sharing it here for anyone else:
const express = require("express");
const app = express();
const port = 8080;
app.use(function( req, res, next ) {
res.setHeader("Access-Control-Allow-Origin", "*");
res.header(
"Access-Control-Allow-Headers",
"Content-Type"
);
res.sendStatus(200);
let data = "";
req.on("data", function( chunk ) {
data += chunk;
console.log(data);
next();
});
});
app.listen(port, () => console.log(`Listening on port ${port}`));