I need to create and action that returns whether or not the user's session has expired. The problem is that requesting any action will refresh the user's session timeout. So, I need this action to NOT refresh the timeout.
Is there some way to make a controller action that has access to the session, but does not refresh the timeout?
Figured it out. We built an http module to read the forms auth ticket which could be accessed at site.com/.formsauthticket. By handling it at this level, it did not trigger the session at all. I'm afraid I cannot provide code here but we set the module to return the number of milliseconds till the session expired. We then used this number to make some client-side timers.
We based our solution on an answer to a different question found here. Hope this helps someone else!
Related
I can redirect a user to home page upon session logout.. this was very simple. However, if an user had logged into the app and had the page open, even on session time out, he is able to perform all the functions(this is bad).
The redirect does not happen until the page is refreshed, or submitted to the server... there are some update functions that could be done by the user even if he is not currently logged in... I have done a lot of research but unable to fix this solution. I also found this thread but it seems to have no proper answer:
Spring Security 3.1 - Automatically redirect to login page when session-timeout occurs
For example, most of the banking sites log you out after a time out.. they do not wait until you come back and then submit a request before you are redirected to home page.
HTTP is stateless. To achieve some form of state the server can maintain a session for each user by giving them a session id on their first request. The user would have to resend that session id on each future request to identify that the other requests happen within the same session.
Because the session is maintained by the server, there is no way to notify the client that the session has timed out.
Instead, if the user makes a new request when the session is timed out, their session ID is no longer good and therefore you can take a particular action like redirect them to login page.
Assuming nothing works out. You may want to consider below mentioned approches:
Approach 1:
Create a cookie on browser and have encrypted timestamp in it that will contain last visited/request timestamp from browser, for each request first get get this cookie value and compare with the pre-defined session out time, if session-out time reached then redirect user to error page else serve the request. On logout delete the cookie.
Why encrypted value for timestamp: if somehow user gets to know about cookie used for session timeout then (s)he can change this value in browser and keep on sending this request.
Approach 2:
You can also achieve this by making an entry in your database for every logged-in user and updating timestamp in this database for each request. For each incoming request get this timestamp from database and compare it with pre-defined value for timeout and handle accordingly. On logout delete the entry.
In both the approaches explicitly perform response.redirect("errorPageUrl");
I don't really deeply understand of the session mechanism but just good enough as a casual user of the technology. I have a page implemented with jQuery ajax request. If I keep refreshing the page at a fast pace it would make the session expired and I have to login again. I would appreciate for an explanation of the phenomenon and solution to prevent that.
Sessions consists in to main parameters
Cookies and Server-side session data
In a very little explanation
cookies contains session ID, that references to the server to get session data. Server then fetchs data with the session ID and matches it inside a file with various parameters.
Your problem must be session timeout, it depends mainly on session timeout parameter configured.
Your ajax requests only works if the session timeout hasnt expired thats why it prompts you for login.
You can solve this by defining a service that does not require authentication, you can define your functions on a specific file with no session initialization so the request can bypass the security session, and your other pages that need security are secured at the same time. Like amazon mechanism.
I am new to lift and trying to write a simple login application. When I leave my login page for some time, and I enter username and password it doesn't login instead it perform session expire behavior.
I checked the log and found that whenever I got INFO - Session navoo0xdu1ia1vi8m1c0cnl3w expired log message, the above behavior happens.
I am not able to understand why request is using the existing session, even if it's already expired. Please guide me where can I found documentation/example/tutorial to understand this behavior and how to implement simple session based login functionality.
Any help will be appreciated since this problem is bottleneck to me. I googled a lot but couldn't find anything useful.
If your session is expiring then it is because of one of two things:
1) The value set in LiftRules.sessionInactivityTimeout
or
2) The value set for session expiry within your container session.
The former is actually set to nothing by default, which means the latter will override it. Be aware however that provided you are interacting with Lift and have not disabled the heartbeat pulse then sessions do not expire. If you watch the AJAX traffic you will notice a page heartbeat used for function GC which keeps the page bound functions alive.
When do you call getPageContext().getSession().invalidate()?
I tried calling that at the logout page, then cflocation it back to the main page, and it throws exception.
How to assign a new session right after?
The documentation says:
You cannot destroy the session and
create a session on the same request,
as creating a new session involves
sending session cookies back.sending session cookies back.
I thought cflocation to the main page already qualifies as a different request, is it not?
getPageContext().getSession().invalidate() will invalidate the session, subsequent request with that sessionID will get an error trying to access the Session scope but the memory will not be reclaimed until the actual session timeout.
What you can do is session.setMaxInactiveInterval(int) set it to very a low number in ms so it expires right away and release the memory. Then do a cflocation and for safe mesure use addToken="no"
Ben Nadel had series of posts related to "killing" session. As I remember it's not as easy as one method call. I'd google those.
you can use any of these for ur user logout function
1) Session.Remove(key)
2) Session(key) = nothing
Both are fine. But the later one is better if the user might want to re login or you actually....saves the effort of recreating a new key.
How do websites generally log users out and send them to the log in screen automatically when a user's session expires? Is this done through ajax or running async handlers? Can you give me a bit of an explanation.
Banks and such use a client-side timeout via javascript, or something similar. Really, though, the server handles the actual session, so if you disabled the client-side logic it would act as if you were attempting to make transactions while logged out.
Use a cookie as well as a session.
Cookie must be set when a session is
started.
If the cookie is present but the
session is gone, redirect to the
login screen.
If there is no session and no cookie
do nothing
(pardon me if you can't do that because I never used ASP and basing my answer on my PHP knowledge)
Typically, you set an expiration timestamp on your session ID cookie. When the cookie fails to be sent, the client is logged off (no given session ID).
This method is often combined with JavaScript and another timestamp token. When the timers start running down, a notification is sent that allows the user to "refresh" their session... essentially, making a request before the session timestamp expires.
The "refresh" request could be anything, even something as simple as an image load.
If you are using Tomcat you can use its built in <security-constraint> mechanism within your web.xml definition. All of the timing, login screen, and page redirects are handled by Tomcat with little effort on your part other than definitions.
Oh, IIS... nevermind.