dashy/services/cors-proxy.js
2022-01-21 13:00:26 +00:00

48 lines
1.4 KiB
JavaScript

/**
* A simple CORS proxy, for accessing API services which aren't CORS-enabled.
* Receives requests from frontend, applies correct access control headers,
* makes request to endpoint, then responds to the frontend with the response
*/
const axios = require('axios');
module.exports = (req, res) => {
// Apply allow-all response headers
res.header('Access-Control-Allow-Origin', '*');
res.header('Access-Control-Allow-Methods', 'GET, PUT, PATCH, POST, DELETE');
if (req.header('access-control-request-headers')) {
res.header('Access-Control-Allow-Headers', req.header('access-control-request-headers'));
}
// Pre-flight
if (req.method === 'OPTIONS') {
res.send();
return;
}
// Get desired URL, from Target-URL header
const targetURL = req.header('Target-URL');
if (!targetURL) {
res.status(500).send({ error: 'There is no Target-Endpoint header in the request' });
return;
}
// Apply any custom headers, if needed
const headers = req.header('CustomHeaders') ? JSON.parse(req.header('CustomHeaders')) : {};
// Prepare the request
const requestConfig = {
method: req.method,
url: targetURL,
json: req.body,
headers,
};
// Make the request, and respond with result
axios.request(requestConfig)
.then((response) => {
res.status(200).send(response.data);
}).catch((error) => {
res.status(500).send({ error });
});
};