What are the available events offered by Express websockets?

Question

What are the available events offered by Express websockets?

I am interested in learning about the different websocket events available. Currently, I have only used the ws.on('message') event, but I would like to find out how to detect when the connection is established and closed. I attempted to add the ws.on('connection') event, but it did not work.

This is my code:

app.ws('/', function (ws, req) {
    ws.on('message', function (textChunk) {
            //do something
        }
    });
});

Do I need to implement some client-side programming for this functionality?

I also tried adding the following code, but it did not trigger when I connected from my client.

ws.on('request', function () {
  console.log("request");
});

javascript node.js express websocket

Answer 1

Answer №1

The app.ws function is used to define the behavior when a new websocket connection is established. Here is an example of how you can use it:

app.ws('/', function (ws, req) {

    console.log("A new connection has been opened!");

    ws.on('close', function() {
        console.log('The connection was closed!');
    });

    ws.on('message', function (message) {
        console.log('Message received: '+message);
    });
});

Answer 2

The app.ws function is used to define the behavior when a new websocket connection is established. Here is an example of how you can use it:

app.ws('/', function (ws, req) {

    console.log("A new connection has been opened!");

    ws.on('close', function() {
        console.log('The connection was closed!');
    });

    ws.on('message', function (message) {
        console.log('Message received: '+message);
    });
});

Answer 3

Answer №2

Upon analyzing the source code of express-ws, it appears that the following actions can be performed.

const express = require('express');
const app = express();
const expressWs = require('express-ws')(app);

// retrieve the WebsocketServer instance with getWss()
expressWs.getWss().on('connection', function(ws) {
  console.log('connection open');
});

// ... express middleware

// ... websocket middle ware
app.ws('/', function(ws, req) {
  ws.on('message', function(msg) {
     console.log(msg);
  });
});

app.listen(3000);

New Response

The available options include:

close
error
message
open

Visit this link for more details on WebSocket attributes.

Answer 4

Upon analyzing the source code of express-ws, it appears that the following actions can be performed.

const express = require('express');
const app = express();
const expressWs = require('express-ws')(app);

// retrieve the WebsocketServer instance with getWss()
expressWs.getWss().on('connection', function(ws) {
  console.log('connection open');
});

// ... express middleware

// ... websocket middle ware
app.ws('/', function(ws, req) {
  ws.on('message', function(msg) {
     console.log(msg);
  });
});

app.listen(3000);

New Response

The available options include:

close
error
message
open

Visit this link for more details on WebSocket attributes.

Answer 5

Answer №3

After some digging, I managed to discover another event that is actually triggered. If only I could come across one that is called just once upon opening the connection.

app.ws('/', function (ws, req) {

    ws.on('close', function() {
        console.log('connection closed');
    });

    ws.on('message', function (textChunk) {
            //adding functionality here
        }
    });
});

Answer 6

After some digging, I managed to discover another event that is actually triggered. If only I could come across one that is called just once upon opening the connection.

app.ws('/', function (ws, req) {

    ws.on('close', function() {
        console.log('connection closed');
    });

    ws.on('message', function (textChunk) {
            //adding functionality here
        }
    });
});

What are the available events offered by Express websockets?

Answer №1

Answer №2

New Response

Answer №3

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