Detect disconnected websocket in framework after navigation or page unload - javascript

I'm using a web framework where everything gets passed through a websocket. New / updated DOM elements are shipped over to the browser, events get shipped back to the server. Works great. Except when the websocket gets closed.
This happens...
when using desktop/mobile Safari's browser navigation buttons are used to leave & come back to the page
on mobile Safari after a timeout when switching to a different app, tab or screen locking
when the WiFi goes down etc.
After that the user simply sees a normal looking page, but everything is obviously dead as no more updates happen and no more events get relayed to the server. I'd like to simply refresh the page in that case. Either everything goes back to normal or the user sees a connection error in case of no network etc.
I tried poking around in the framework's code, adding "window.location.reload(true);" to the "onclose" handler for the websocket kinda does the trick. My state is 100% on the server, so reloading the page will just fix things.
Assuming I can't modify / fix the web framework I'm using, and it doesn't have any onConnectionLost client-side event, what's my best option to detect this scenario and reload the page? Are there any events like 'onPageDisplayedButNotProperlyReloaded', 'onPageVisibleButHasBecomeStaleInTheMeantime', 'onWebSocketsClosed' for me to use? Can I just open some dummy websocket and reload the page when it gets closed or something? Any other good way to detect this?
Thanks!

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WebSocket messages not triggering Javascript eventListeners on refresh only

I'm having issues with my Socket.IO project.
It's a complex back-office built with create-react-app. There is a lot of different web sockets handlers all over the project. It's nicely architectured, so there is a low amount of messy code. Nevertheless, on one of my pages (the main one), the server is sending every 5s some live metrics through web sockets to any of the clients connected to that main page.
If I take a look at my client app, everything works fine:
The update live metrics happens every 5s as expected
If I stay on that page, reload the page. Then the messages keeps coming every 5s:
As seen in the WS Network panel pf the Chromium devtools
But the Javascript eventListeners are not triggered. I've tested to see if they were setted properly after the refresh and it's true. I'm not sure where to look more to debug this.
I thought that if the network is recevings the web socket messages and that the listeners are setted up, there is no reason that the callback function is not called.
Thanks in advance,

How to detect web page crash (not browser crash) using PHP?

How can we detect through PHP or maybe in node.js or other languages if a web page crashed (without the browser EXITing) so that when a user press the "reload" button on the "Aw Snap" page in chrome certain specific content inside the page can be shown in this particular case (crash case).
In a crash without EXIT, a browser shows per example in Google Chrome the famous "Aw, Snap!" page.
I don't want to know how to capture if the user refreshed the page or the page reloaded which can be known quite easily with different methods [one example see this PHP this code which can detect if users refreshed the page on major desktop/mobile browsers except IE unfortunately this code does not capture a crash event and the fact that user might request again the same page after a crash.
I tried using "register_shutdown_function", and some other maneuvers using connection PHP functions like "connection_aborted" etc... but with no success. I figure out a sloppy way through the use of session variables but probably there are better clever manoeuvres.
Any help or suggestion would be greatly appreciated. Any solution in nodejs will be also welcomed.
web brower crash because too many process from your browser to PC of Client.
this crash can't detected by php because PHP server scripting. and you have question.., why not use JS for detect crash of browser?, because JS created just for controller website,. if you force to checked that use ajax, node, etc you can't do that, why? because the problem comes suddenly
and detected crash browser from php is impossible.

Close a browser tab opened by Android app

I have an issue where I'm asking my app to open a browser looking at my Server.
From that server page, The user can perform some stuff on an existing site, then redirects the user to a URL that the App catches and the App continues as normal.
The lifecycle looks like this:
App -> Web Site -> App
However, after the life cycle of the app and the app is closed, the webpage is still open in the browser (on the page where the redirect to the app occurred).
It's apparently difficult via javascript to close a tab which wasn't opened by javascript? (In my case, the tab was opened by the app, not by a different tab). Is there any way to get around this?
(I'm aware I could use a WebView, but WebViews are buggy, manufacturer specific, security holes that I want to avoid)
No, sorry. There is no standard Intent structure for this. While it is possible that some browsers offer something, I am not aware of any that do.
Bear in mind that there is no requirement that your ACTION_VIEW Intent open up a browser tab, as the user's chosen browser may not offer any sort of tab UI metaphor. check this reference old question

Refreshing same browser window from windows run command

I have one web application. When client enters the address and after successfully logging in. He gets the home page with some data over the page. Now when any third party tool or from run command if i give the same url on which the client is with changed parameter values, i want the same browser window to be refreshed with updated/changed values without opening the new browser window.
Whats happening now is that when i'm triggering the url from different source, its opening in new browser window. Plz help me out with few suggestions.
Ars.
The best solution would be for the web application to poll the server and refresh itself when there is an update.
Your command line tool can then contact the server and update the parameters directly, and the application in the user's browser will pick up those changes automatically.
Attaching to a running Internet Explorer instance is also possible, for example see this article: http://www.codeproject.com/Articles/9683/Automating-Internet-Explorer, or the Selenium project at http://seleniumhq.org/. But you're almost certainly going to make it easier for yourself by changing your application to refresh automatically.

Call onunload function from iframe

I am working on a multiplayer chess game as a Facebook app.
If one player leaves the game by closing the browser the other player should get a notification. So if one player closes the Browser, a unlink function should be called to unlink the player. This works fine with onunload outside Facebook.
The problem is, that the Facebook apps are loaded in iframes and the onunload event doesn't work there.
So I need a way to call a function inside an iframe when a user is closing the browser.
This is probably not the answer you are looking for but "logging off" on unload will never work reliably. For an extreme example, consider the case where the browser crashes or is killed via the Windows task manager. So you better implement an additional mechanism to detect whether a user left. Typically this is done by sending a request to the server periodically. If this request isn't received for a significant time (meaning something that cannot be caused by a slow connection or other hiccups) you unlink the user.
That said, I tested Firefox 4 and MSIE 8 and both correctly fire unload event on the frame if the tab or the browser is closed. Chrome 12 doesn't do that, that's probably the browser you have been testing with. I consider it a Chrome bug.

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