Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Allow client filter by websocket url #160

Open
wants to merge 4 commits into
base: master
Choose a base branch
from
Open
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
1 change: 0 additions & 1 deletion .npmignore

This file was deleted.

113 changes: 12 additions & 101 deletions README.md
Original file line number Diff line number Diff line change
@@ -1,108 +1,19 @@
# express-ws [![Dependency Status](https://snyk.io/test/github/henningm/express-ws/badge.svg)](https://snyk.io/test/github/henningm/express-ws)

[WebSocket](https://developer.mozilla.org/en-US/docs/Web/API/WebSockets_API) endpoints for [Express](http://expressjs.com/) applications. Lets you define WebSocket endpoints like any other type of route, and applies regular Express middleware. The WebSocket support is implemented with the help of the [ws](https://github.com/websockets/ws) library.

## Installation

`npm install --save express-ws`

## Usage

__Full documentation can be found in the API section below. This section only shows a brief example.__

Add this line to your Express application:

```javascript
var expressWs = require('express-ws')(app);
```

__Important: Make sure to set up the `express-ws` module like above *before* loading or defining your routers!__ Otherwise, `express-ws` won't get a chance to set up support for Express routers, and you might run into an error along the lines of `router.ws is not a function`.

After setting up `express-ws`, you will be able to add WebSocket routes (almost) the same way you add other routes. The following snippet sets up a simple echo server at `/echo`. The `ws` parameter is an instance of the WebSocket class described [here](https://github.com/websockets/ws/blob/master/doc/ws.md#class-websocket).

```javascript
app.ws('/echo', function(ws, req) {
ws.on('message', function(msg) {
ws.send(msg);
});
});
```

It works with routers, too, this time at `/ws-stuff/echo`:

```javascript
var router = express.Router();

router.ws('/echo', function(ws, req) {
ws.on('message', function(msg) {
ws.send(msg);
});
});

app.use("/ws-stuff", router);
```

## Full example
#
Only difference from [express-ws](https://snyk.io/test/github/henningm/express-ws)
is the method getWssClients(url) that fetchs clients of a given URL

```javascript
var express = require('express');
var app = express();
var expressWs = require('express-ws')(app);

app.use(function (req, res, next) {
console.log('middleware');
req.testing = 'testing';
return next();
app.ws('/a', function(ws, req) {
});

app.get('/', function(req, res, next){
console.log('get route', req.testing);
res.end();
app.ws('/b', function(ws, req) {
});

app.ws('/', function(ws, req) {
ws.on('message', function(msg) {
console.log(msg);
});
console.log('socket', req.testing);
});

app.listen(3000);
//Fetch clients subscribed to route /a
const clientsA = expressWs.getWssClients("/a")
clientsA.forEach(client => {client.send("Hello clients from route /a")})

//Fetch clients subscribed to route /b
const clientsB = expressWs.getWssClients("/b")
clientsB.forEach(client => {client.send("Hello clients from route /b")})
```

## API

### expressWs(app, *server*, *options*)

Sets up `express-ws` on the specified `app`. This will modify the global Router prototype for Express as well - see the `leaveRouterUntouched` option for more information on disabling this.

* __app__: The Express application to set up `express-ws` on.
* __server__: *Optional.* When using a custom `http.Server`, you should pass it in here, so that `express-ws` can use it to set up the WebSocket upgrade handlers. If you don't specify a `server`, you will only be able to use it with the server that is created automatically when you call `app.listen`.
* __options__: *Optional.* An object containing further options.
* __leaveRouterUntouched:__ Set this to `true` to keep `express-ws` from modifying the Router prototype. You will have to manually `applyTo` every Router that you wish to make `.ws` available on, when this is enabled.
* __wsOptions:__ Options object passed to WebSocketServer constructor. Necessary for any ws specific features.

This function will return a new `express-ws` API object, which will be referred to as `wsInstance` in the rest of the documentation.

### wsInstance.app

This property contains the `app` that `express-ws` was set up on.

### wsInstance.getWss()

Returns the underlying WebSocket server/handler. You can use `wsInstance.getWss().clients` to obtain a list of all the connected WebSocket clients for this server.

Note that this list will include *all* clients, not just those for a specific route - this means that it's often *not* a good idea to use this for broadcasts, for example.

### wsInstance.applyTo(router)

Sets up `express-ws` on the given `router` (or other Router-like object). You will only need this in two scenarios:

1. You have enabled `options.leaveRouterUntouched`, or
2. You are using a custom router that is not based on the express.Router prototype.

In most cases, you won't need this at all.

## Development

This module is written in ES6 and uses ESM.
21 changes: 21 additions & 0 deletions examples/url-filter-broadcast.js
Original file line number Diff line number Diff line change
@@ -0,0 +1,21 @@
var express = require('express');
var expressWs = require('..')

var expressWs = expressWs(express());
var app = expressWs.app;

app.ws('/a', function(ws, req) {
});

app.ws('/b', function(ws, req) {
});

setInterval(function () {
const clientsA = expressWs.getWssClients("/a")
const clientsB = expressWs.getWssClients("/b")

clientsA.forEach(client => {client.send("Hello clients from route /a")})
clientsB.forEach(client => {client.send("Hello clients from route /b")})
}, 5000);

app.listen(3100)
10 changes: 10 additions & 0 deletions src/index.js
Original file line number Diff line number Diff line change
Expand Up @@ -43,6 +43,8 @@ export default function expressWs(app, httpServer, options = {}) {
const wsServer = new ws.Server(wsOptions);

wsServer.on('connection', (socket, request) => {
socket.wsUrl = request.url;

if ('upgradeReq' in socket) {
request = socket.upgradeReq;
}
Expand Down Expand Up @@ -79,6 +81,14 @@ export default function expressWs(app, httpServer, options = {}) {
getWss: function getWss() {
return wsServer;
},
getWssClients: function getWssClients(url) {
if (!url) {
return wsServer.clients;
}

const clients = Array.from(wsServer.clients);
return clients ? clients.filter((client) => client.wsUrl === url) : [];

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

This won't work properly for use-cases that use URL path parameters

ex: if you have something like /chat/:id, you would want to get all clients for a specific ID

},
applyTo: function applyTo(router) {
addWsMethod(router);
}
Expand Down