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---
author: clemensv
ms.service: azure-relay
ms.topic: include
ms.date: 01/24/2026
ms.author: clemensv
---
### Create a Node.js application
Create a new JavaScript file called `listener.js`.
### Add the Relay package
Run `npm install hyco-ws` from a Node command prompt in your project folder.
### Write some code to receive messages
1. Add the following constant to the top of the `listener.js` file.
```js
const WebSocket = require('hyco-ws');
```
2. Add the following constants to the `listener.js` file for the hybrid connection details. Replace the placeholders in brackets with the values you obtained when you created the hybrid connection.
- `const ns` - The Relay namespace. Be sure to use the fully qualified namespace name; for example, `{namespace}.servicebus.windows.net`.
- `const path` - The name of the hybrid connection.
- `const keyrule` - Name of your Shared Access Policies key, which is `RootManageSharedAccessKey` by default.
- `const key` - The primary key of the namespace you saved earlier.
3. Add the following code to the `listener.js` file:
```js
var wss = WebSocket.createRelayedServer(
{
server : WebSocket.createRelayListenUri(ns, path),
token: WebSocket.createRelayToken('http://' + ns, keyrule, key)
},
function (ws) {
console.log('connection accepted');
ws.onmessage = function (event) {
console.log(event.data);
};
ws.on('close', function () {
console.log('connection closed');
});
});
console.log('listening');
wss.on('error', function(err) {
console.log('error' + err);
});
```
Here's what your listener.js file should look like:
```js
const WebSocket = require('hyco-ws');
const ns = "{RelayNamespace}";
const path = "{HybridConnectionName}";
const keyrule = "{SASKeyName}";
const key = "{SASKeyValue}";
var wss = WebSocket.createRelayedServer(
{
server : WebSocket.createRelayListenUri(ns, path),
token: WebSocket.createRelayToken('http://' + ns, keyrule, key)
},
function (ws) {
console.log('connection accepted');
ws.onmessage = function (event) {
console.log(event.data);
};
ws.on('close', function () {
console.log('connection closed');
});
});
console.log('listening');
wss.on('error', function(err) {
console.log('error' + err);
});
```
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