php session logout

chrisleon

I have a database of users.

In this database, there is a field of whether the user is logged in (Y/N).

When they login, the field updates to a Y.

I still have not figured out to change the field to a N when they exit there browser.
I have a logout button that is an easy way to change the field as long as they click it.

Is there a way to do this in case they just close the browser. Maybe a session timeout. I know banks do it all the time on there websites.

I am just trying to alleviate multiple people trying to login into the same account and order product.

devinemke

rather than storing the login as a boolean (Y or N) i suggest your store it as a DATETIME field. have the field default to NULL. when someone logs in set the login field to the current time and update the field on every page request. then run a cron every 10 minutes or whatver that queries the user table for all login times that are older than 10 minutes (or whatever timeout you want) and updates them back to NULL.

chrisleon

That is a really good idea. Thank you

chrisleon

Ok, I thought i was done, but I have one more question. I placed a quick update in all the pages that would be or could be visited. I do a quick update of datetime and it works great.

I am very familiar with cron's, but my main question is:

Is there a quick convert of the datetime value that I can check for 10 minutes later. I have done time conversions before:

$beghour = date(H) 3600;
$begmin = date(i) 60;
$begsec = date(s);

$begintime = $beghour + $begmin + $begsec;

$endhour = date(H) 3600;
$endmin = date(i) 60;
$endsec = date(s);
$endtime = $endhour + $endmin + $endsec;

$totaltime = $endtime - $begintime;
echo "$totaltime seconds";

Is this what I want to do, or something similar?

devinemke

i think you are overcomplaicting this. when someone is logged in, on each page request do a query like this:

UPDATE users SET login = NOW() WHERE userid = $userid

so as a user moves around your site they will be updating with the current time. any user that is inactive for 10 minutes can be logged out automatically with the following query:

UPDATE users SET login = NULL WHERE login < DATE_SUB(NOW(), INTERVAL 10 MINUTE)

run this via a cron every 10 minutes

note: i'm assuming your are using mySQL

chrisleon

I never realized that mysql had the power to do that. I do must of my stuff via php and very little sql work.

That is so awesome.

You were right, I was incredibly over complicating things.

thanx again.