cors-bypass
Advanced tools
Bypass the browsers CORS restrictions, without needing to setup a server-side proxy.
Bypass the browsers CORS restrictions, without needing to setup a server-side proxy. Demo
WebSocket API specIt uses postMessage to send cross-domain events, which is used to provide mock HTTP APIs (fetch, WebSocket, XMLHTTPRequest etc.). Simplified version
Theres three components to this module: the Server, Adapter and Client.
Simply serve a HTML file on a domain from which you want to make requests from (HTTP domain for example), with the following (use a bundler like Webpack, Parcel etc):
import { Server } from 'cors-bypass'
const server = new Server()
<body>
<script src="./node_modules/cors-bypass/lib/server.bundle.js"></script>
</body>
Next you need a HTML file from the domain that will make requests (your web app's domain). The adapter is in control of forwarding requests from a client located on any page of your site, to the server (using a BroadcastChannel).
import { Adapter } from 'cors-bypass'
const adapter = new Adapter()
<body>
<script src="./node_modules/cors-bypass/lib/adapter.bundle.js"></script>
</body>
As long as the Adapter is running in a different tab (on the same domain as the client), you will be able to make requests.
// Located somewhere on https://your-site.com
import * as BypassCors from 'cors-bypass'
const client = new BypassCors.Client()
await client.getServer() // null - no server connected yet
await client.openServerInNewTab({
serverUrl: 'http://random-domain.com/server.html',
adapterUrl: 'https://your-site.com/adapter.html'
})
await client.getServer() // { id: 123, url: 'http://random-domain.com/server.html' }
// Create a WebSocket (websocket is loaded in the server tab, but it's API is available on this page)
const ws = new BypassCors.WebSocket('ws://echo.websocket.org')
ws.onopen = () => ws.send('hello')
ws.onmessage = ({ data }) => console.log('received', data)
As using a Service Worker require HTTPS, it's impossible to connect to local devices which only support HTTP.
Using this module does requires the user to open an extra window, but it lets you bypass cors.
FAQs
Bypass the browsers CORS restrictions, without needing to setup a server-side proxy.
The npm package cors-bypass receives a total of 8 weekly downloads. As such, cors-bypass popularity was classified as not popular.
We found that cors-bypass demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 1 open source maintainer collaborating on the project.
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