How to check that the connection is open?

[majidbigdeli]

What's your idea about this issue that the event will not be caught e.g 5 hours after connecting,
When we press the F5 key (refresh) the problem will be fixed.
Is it possible for network problems ? If the problem is this, how to fix it?
E.g. sending a request to the server again for connecting

[kataras]

Hmmm I don't quite understand, can you please describe it a bit more?

[majidbigdeli]

Yes, the explanation is complicated, and my explanation was bad.
How to check that the connection is open?

[majidbigdeli]

Of course, I have not seen any problems so far.
I just want to re connect if the connection was interrupted. Without refresh page.

[kataras]

aaa you talk about automatic reconnection, yes I had that in mind but let's not hurry, this is an active project and the next update will contain automatic reconnection, we don't have to implement them from version zero, good feature request though.

[majidbigdeli]

@kataras yes I Talk about automatic reconnection.
please see my code .

async function runServer() {
                try {
                    var wsURL = 'wss://wss.ami.dev.iwin.local:3811/echo';
                    const conn = await neffos.dial(wsURL, {
                        default: {
                            _OnNamespaceConnected: function (nsConn, msg) {
                                console.log("connect to server");
                                setInterval(function () { checkConnectStatus(nsConn)}, 10000);
                            },
                            _OnNamespaceDisconnect: function (nsConn, msg) {                            
                                console.log(err);
                            },
                            showForm: function (nsConn, msg) {

                            }
                        }
                    }, { headers: { 'Extension': 2009 } });
                    conn.connect("default");
                } catch (err) {
                    console.log(err);
                }
            }

function checkConnectStatus(nsConn) {
                console.log('checkConnectStatus...')
                var resp = nsConn.emit("heartBit", "");
                if (resp === false) {
                    console.log(resp);
                    var postdata = {};
                    postdata["category"] = 'PopUp_Error';
                    postdata["customData"] = JSON.stringify(resp) ;
                    postdata["desc"] = 'server is disconect during work!';
                    postdata["message"] = 'server is disconect during work!';
                    logError(postdata);
                    console.log('server is disconect!')
                    console.log('reconnected...')
                    runServer();
                }
            }

I have a lot of '''server error disconect during work!'''

my log in database

[kataras]

OK let me implement it now then :)

[kataras]

However you can check if it's closed by nsConn.conn.isClosed() *

[majidbigdeli]

@kataras thank you . You're so good .

@kataras

I really owe you Because the projects of iris and neffos have helped me a lot. And when I have a problem, you fix it.

When I used the signalr in .NET or when I used socketio, I had a lot of memory usage problems in browser.

But in neffos, I can open several tabs without a memory usage problem.
Really thank you.

[majidbigdeli]

@kataras
I have another question.
How to send event to a tab from several tabs opened by the user?
For example, check if the user is connected to the server in another tab
Do not connect again to the server in the new tab.
it is important .
Because we want to open a new window when receiving the event.
In this case, several new windows will open.

I'm trying to find a solution to avoid multiple connections over multiple open tabs or multiple browser.

[kataras]

It's my pleasure @majidbigdeli !!!

It's done with neffos.js: d3bb155 and neffos: kataras/neffos@5314c23.

Simple by pass a options.reconnect: 5000 (milliseconds to try reconnect, 0 means disabled, defaults to 0) to the dial function.

neffos.js/_examples/browserify/app.js

Lines 52 to 59 in d3bb155

	}, {
	// if > 0 then on network failures it tries to reconnect every 5 seconds, defaults to 0 (disabled).
	reconnect: 5000,
	// custom headers:
	headers: {
	// 'X-Username': 'kataras',
	}
	});

UPDATE

I also added some features that you didn't ask but I think you will love it, such as count of total retries on suceed reconnection on the server-side.

neffos.js/_examples/browserify/app.js

Lines 36 to 39 in 91eb944

	_OnNamespaceConnected: function (nsConn, msg) {
	if (nsConn.conn.wasReconnected()) {
	addMessage("re-connected after " + nsConn.conn.reconnectTries.toString() + " trie(s)");
	}

neffos.js/_examples/server.go

Lines 91 to 94 in 91eb944

	srv.OnConnect = func(c *neffos.Conn) error {
	if c.WasReconnected() {
	log.Printf("[%s] connection is a result of a client-side re-connection, with tries: %d", c.ID(), c.ReconnectTries)
	}

[kataras]

@majidbigdeli You need to communicate across web browser windows, this requires some knowedge about the window api and how postMessage works, read the links below to learn how:

• https://developer.mozilla.org/en-US/docs/Web/API/Window
• https://developer.mozilla.org/en-US/docs/Web/API/Window/postMessage
• And a good video tutorial to watch about these things is created by @linkedin and @lynda, https://www.lynda.com/JavaScript-tutorials/Web-Security-Same-Origin-Policies/794147-2.html look at its fifth section: Communicating Securely across Browser Windows.

For nodejs and go side there is a wrap-users-conn example at the neffos repository.

Hope I helped you

[majidbigdeli]

@kataras You are wonderful.

[kataras]

Thanks @majidbigdeli !!! I updated the API a bit giving some more information on the connection itself, go: Conn.ReconnectTries int and Conn.WasReconnected() bool (the server can decide if allow this reconnection or not or after how much tries is not allowed for example), js: nsConn.conn.reconnectTries number and nsConn.conn.wasReconnected() boolean (on javascript we don't have a limit of maximum tries, this can be implemented easly if some1 ask, it doesn't mean a lot though) :)

see my comment above

[kataras]

Updated: reconnection is available on nodejs side as well.

[majidbigdeli]

hello @kataras
When I disconnect and reconnect the network, I get error.
neffos.min.js?v980406:1 Fetch API cannot load wss://wss.ami.dev.iwin.local:3811/echo. URL scheme must be "http" or "https" for CORS request.

[kataras]

@majidbigdeli, no need to duplicate the issues, this belongs to this repository:P

neffos.js/src/neffos.ts

Lines 871 to 874 in ca73e99

	let endpointHTTP = endpoint.replace("ws://", "http://");
	if (endpoint.startsWith("wss://")) {
	endpointHTTP = endpoint.replace("ws://", "https://");
	}

neffos.js/src/neffos.ts

Line 884 in ca73e99

_fetch(endpointHTTP, fetchOptions).then(() => {

But yes... javascript replace works with regexp, funny that it worked locally, anyway...

I'll replace it with this one instead: let endpointHTTP = endpoint.replace(/(ws)(s)?\:\/\//, "http$2://"); please update and tell me if that did the job.

Sorry for the delay but I was working with the wiki and a pdf book of the neffos (on the neffos/README).

[majidbigdeli]

@kataras I am Sorry.
Sorry . I did not know it is a client or server problem.

[kataras]

Hey no worries @majidbigdeli !!!

Does the new neffos.js version fixed the issue?

[majidbigdeli]

@kataras

I get another issue

I get
neffos.min.js?v980406:1 HEAD https://wss.ami.dev.iwin.local:3811/echo net::ERR_NETWORK_CHANGED
in disconnect network

and when I re connect network i get
Access to fetch at 'https://wss.ami.dev.iwin.local:3811/echo' from origin 'https://dev.iwin.ir' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.

I get two server ; 1 panel (https://dev.iwin.ir) and 2 neffos server (wss.ami.dev.iwin.local:3811) that this call in panel

[kataras]

OK that's normal, first of all:

The ERR_NETWORK_CHANGED as I describe in my code comments, is coming from the google chrome browser and there is no way to disable it ( we could clear the whole console's browser but that way any custom log messages would be dissapear and we don't want that).

neffos.js/src/neffos.ts

Lines 868 to 869 in 374700d

	// Chrome itself is emitting net::ERR_CONNECTION_REFUSED and the final Bad Request messages to the console on network failures on fetch,
	// there is no way to block them programmatically, we could do a console.clear but this will clear any custom logging the end-dev may has too.

The second one is easy to fix, I wanted to do it but I didn't think was necessary, as it seems it is. Update to 0.0.18 and tell me the results, thanks a lot @majidbigdeli

[majidbigdeli]

thanks a lot @kataras
I fix issue with add cors in server side

	serveMux := http.NewServeMux()
	serveMux.Handle("/echo", server)
	th := http.HandlerFunc(timeHandler)
	broadcast := http.HandlerFunc(broadcastHandler)
	serveMux.Handle("/time", th)
	serveMux.Handle("/broadcast",broadcast)

	handler := cors.Default().Handler(serveMux)
        log.Fatal(http.ListenAndServeTLS(addr, certPath, keyPath, handler))

.

But I now see Your last Commit( 7384e2d ) for version 0.0.18
Thank You my friend.

[kataras]

Nice @majidbigdeli , however, you don't need an external middleware for that, just set a header:

w.Header.Set("Access-Control-Allow-Origin", "*")

can I ask why you don't use Iris in this one? You can use it with Iris v11.1.1 too:

app.Get("/echo", iris.FromStd(server))

and on v11.2.0 you can optionally do the following to have iris.Context access too:

import (
  // [...]
  "github.com/kataras/iris/websocket"

  "github.com/kataras/neffos"
)

app.Get("/echo", websocket.Handler(server))

neffos.OnNamespaceConnected: func(nsConn *neffos.NSConn, msg neffos.Message) error {
  // with `websocket.GetContext` you can retrieve the Iris' `Context`.
  ctx := websocket.GetContext(nsConn.Conn)
  // [...]
}

[majidbigdeli]

@kataras yes . I just use iris . Thank you .
I use the neffos in the company for the voip project with 60,000 daily calls.
I open the crm form with the neffos on the incoming call.
Neffos is great.
Everyone should know and use neffos.

[kataras]

You are amazing @majidbigdeli thank you for your truly support once again!

Earlier today I've pushed a new Iris feature that some of my clients wanted as well, it's not the correct repository and issue to describe it, but in short it offers request authentication and verification that your company may want to use at: https://github.com/kataras/iris/blob/660849d01ce59cf926ffbb6df83d1385cdb239db/_examples/authentication/request/main.go

[majidbigdeli]

You are amazing @majidbigdeli thank you for your truly support once again!

Earlier today I've pushed a new Iris feature that some of my clients wanted as well, it's not the correct repository and issue to describe it, but in short it offers request authentication and verification that your company may want to use at: https://github.com/kataras/iris/blob/660849d01ce59cf926ffbb6df83d1385cdb239db/_examples/authentication/request/main.go

@kataras I read this. Thank you.