[Resolved] limit session to one

jassh

hi there all..

okay, i was just wondering..
i've been playing around with this concept for quite some times
but this experimentation is getting me no where

it goes sumthin like this..

i have a login page..
so once a person login, he can choose 1 link from a total of 3
that lead him to a page.., say page 1

now, i want to make it so that,
if a person logs on to the 1st page,
no body can visit the page, unless that guy logs off
in other word, the link to the 1st page is not clickable

now, i manage to do so by implementing a database,
the databse will have this table that contains:
- user_id (example: jassh)
- time_in (example: 2003-05-21-14-00-00 ,or something like that)
- page (example: page1)

means, when a person logs in, and click PAGE 1 LINK
the database records the persons ID,
the timestamp (when he logs in), and the page he choose
and also, it create a session for the person..

so when another person logs in,
the 'chose your link' page will query the db,
if page1 exist, than link to page1 is not clickable

and when the person who visit page 1 logs out,
the database will "delete * where user_id = 'jassh'"

now, everything went fine..
except, if a person did not log out, but close it browser instead,
means, the system is unable to "delete * where user_id = 'jassh'"

than, the page is locked, unless i go and delete it manually from the db.

of course, the system will delete it after a certain span of time,
triggered when someone logs in
but till then, the page locked

so, based on this long story of mine,
how do i make so it is mandatory for the person to log off,
or perhaps make the system checks if the guy is still there..

is this even possible..???

i believe if i can understand how the "user browsing this forum"
used in this forum works, i probably can get somewhere

hope this is not too complex
thanks in advanced..

-jassh

ir4z0r

I used to change the session-save dir (session_save_path())
to a directory in my own one (sessions/).
each time, the user refreshes/enters the page, the script checks
whether the session is older than 5 min, if it is, delete it, if it's not,
touch() it to set its timestamp to now.
So the page can be seen to be left, if the user didn't refresh a page
for 5 min.

this concept works with a DB, too, just store the timestamp of the
user's enter time

tsinka

Hi,

the only way I can think of is to use a little bit of javascript code that opens a very small window if someone closes the window. In that window you could then load a php script that deletes that user from the database. The following code should work with IE and some versions of Netscape. Some versions of Netscape don't support onUnload you'll then have onClose for those, too. IE doesn't support onClose.

It worked with IE6 in my tests but I couldn't test other versions/browsers.

Seems like the X and Y coordinates of the cross in the upper right corner are both negative when the close button is pressed and are not both negative on any other action. It even works with my IE 6 if I select File->Close or press <alt>+<f4>.

<html>
<head>
<SCRIPT language=javascript type="text/javascript">
<!--
function logout()
{
    window.open("http://www.site.com/logout.php?user_id=100", "logout","width=10, height=10");

}

function checkClose() // for IE
{
  if ((window.event.clientY < 0) && (window.event.clientX < 0)) {
    window.open("http://www.site.com/logout.php?user_id=100", "logout","width=10, height=10");
  }
}
//-->
</SCRIPT>
</head>
<body onUnload="checkClose();" onClose="logout();">
Content
</body>
</html>

Hope this helps you a little bit, you might need to add some code for other browsers 🙂

jassh

hi there fellas...

wow, thanks for the pointer you guys,
at least i'm going somewhere..

okay..
my friend ir4z0r
like u.. i did set my own session path...
and i did implement the time stamp strategy,

the problem with that is, i want to timestamp out
only when the person logs out of the system..
coz there maybe in some event,
a person might want to stay iddle in a page for quite some time

i'm afraid if i set the time like 5 minutes,
the person who is supposed to be in that page
will eventually got locked out,
coz he does not refresh browser,
and in that window of oppturnity
some one get the chance to logs in and reclaim that page..

still, i did implement that type of timeout strategy
incase a person stays in the page for more than 2 hrs..
and also an admin module that can free a page..

but ur idea was thoughtfull though,
and i really appreciate that..
thanks.. 🙂

to my friend tsinka..

ur idea was creative...
although i personally sucks at java script,
due to lack of exposure..
but it got me thinking of another way using java script

it's like the one at go.icq.com
where if a user close the browser (pressing an X button)
it prompts a confirmation dialogue box..
"do you wanna close this windows [yes] [no]"

wonder how they do that..

still ur idea was implementable,
i'm trying it with several version of browser..
including opera, NS 7.0, IE6
will tell you how it went....

anyway ,
thanks guys for the info,
keep it coming eh...

have a nice day fellas..

-jassh

John_Canyon

I think tsinkas idea would work best for what you are trying to accomplish.

jassh

yup.. i guess java script is the way to do it..
guess i have to take a deep in the cold water of jscript
ouch....
err.. know any good site??

anyway...
thanks for the replies and pointers guys..
really appreciate em'...

take care and have a very cool breezin nice day..

-jassh

//time to click the resolved button..

tsinka

Hi,

the website you mentioned uses onbeforeunload which only IE knows.

Then they have a code like this:

   function onUrlchange () {
      if(GetAppParam('state')!=0) {
         window.event.returnValue= "You are about to navigate away from the ICQ2Go! page."
         window.event.cancelBubble=true;
      }
   }

But that only works with IE. They use a java applet and get that variable state from the applet.

One thing to mention:

If someone has logged out the code above doesn't make sense because the user already logged out and doesn't want to see the popup logout window.

You could set a javascript variable on top of your page .e.g var loggedIn = 1; if someone is logged in. and var loggedIn= 0; if someone is not logged in. In the onUnload page you can then check if someone is logged in:

<html>
<head>
<SCRIPT language=javascript type="text/javascript">
<!--
var loggedIn=0;

function logout()
{
  if (loggedIn) {
    window.open("http://www.site.com/logout.php?user_id=100", "logout","width=10, height=10");
  }
}

function checkClose() // for IE
{
  if (loggedIn) {
    if ((window.event.clientY < 0) && (window.event.clientX < 0)) {
      window.open("http://www.site.com/logout.php?user_id=100", "logout","width=10, height=10");
    }
  }
}
//-->
</SCRIPT>
</head>
<body onUnload="checkClose();" onClose="logout();">
Content
</body>
</html>