Keep-alive forms don't work as expected

[Blanca80]

I am not sure you understand how keep alive works.  It sends a ping so many times per your session timeout setting to reset the countdown.  If the browser stops communication with the server through the ping when it hits your sessiontimeout limit it will close the session.

Appreciate,

Yes, thats what i've understood about keep-alive but, at least in our application, is not working at all, if we left the browser opened with the form but there is no activity the countdown starts after a period of time and finally closes the session and, as it has the keep-alive property on, it hasn't. 

i'll make a couple of tests cases today in order to see if it's a problem of our programming side or its a general bug of intraweb altough that implies to make an isapi application and set it in iis. 

Blanca

It was mentioned before, but there is more than one keep-alive.  See the thread mentioned above for discussion of both.  They do both work, for their (different) purposes.

The only exception I've found is that browsers on mobile devices (iPhone for certain) go dead if they are not in view.  That is, if they are put in background or the phone is closed they go dead and do not send the ping.   I do not know of other browsers that do this but I haven't checked in a while.  

What browser/OS are you using?   IW/Delphi version?

Dan

Hello Dan ,

I hope you are fine. Here's the result of the session log of an application running on Chrome and maded with Delphi 11.3. As you can see, it's running from 11.14 am and not closed by user but remotely ended by application. The application has setted on keep-alive in all the forms, at least the form that was oppened in the browser, and its timeout is for five minutes. I don't know why the sessions suddenly shut down.  

Created at: 21/10/2024 11:14:26
Destroyed at: 21/10/2024 15:08:26
Remote IP address: x9.xx5.1xx.x5
Browser name: Chrome
Browser user agent string: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/129.0.0.0 Safari/537.36
Duration:  3 hours 54 minutes
Request count: 80
Last Access: 21/10/2024 14:08:45

(The remote ip was masked for security reasons) 

You mentioned in the threat that The MyForm.Keepalive works by knowing the timeout delay (X) and sending a message to the server about 3 or 4 times during that time.
It's possible that this isn't going or maybe there's a moment that stops to sending messages?