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perlsessioncgiexpired-sessions

How do you get CGI::Session to expire after a certain interval?


It seems like CGI::Session expire() function only expires after a user is idle for a specified interval. I'm assuming by idle they mean a user hasnt refreshed the page or accessed any others.

While I see that you can force the session to expire by using delete(), what I dont see is a way to automatically force the session to expire whether the use has been idle or not.

Maybe this is not a desired user experience, but for sake of understanding is there a way to do this without having to track the time interval or using any additional libraries?

Also what is the point of CGI::Session::is_expired if session returns a new one when it expires anyway? At least it seems I can't get to an expired state with my script

  sub build_sss{
    my($this) = shift;

    $cgi = $this->cgi_obj();

    my $sid = $this->sid();
    my $sss = CGI::Session->load(undef, $cgi, {Directory=>'tmp'}) or die CGI::Session->errstr();

   #check expired session
    if ( $sss->is_expired() ) {
      my $expired_url = $ENV{'SCRIPT_URI'}.'?expired='.$sid;
      $this->session_status("SESSION_EXPIRED");
      print $cgi->redirect($expired_url); #when expired param is set shows a msg    
    }


    #check if empty create new
    if ( $sss->is_empty() ) {     
      $sss = $sss->new() or $sss->errstr;
      $this->session_status("SESSION_NEW");
      $sss->expire('30s');
      $sss->expire(_TEST_SUB_SESSION => '15s');
    }

    return $sss;
  }

Solution

  • update: so yeah, if you want a session to expire based on creation time, you have to subclass CGI::Session

    1) make sure you have latest version of CGI::Session 2) read CGI::Session::Tutorial 3) write programs that prove your claims, like this CGI::Session expire demo

    #!/usr/bin/perl --
    
    use strict;
    use warnings;
    
    use CGI();
    use CGI::Session();
    
    my ($oneid);
    {
      my $one = CGI::Session->new or die CGI::Session->errstr;
      $one->expire('3s');
      $one->param(qw' var value ');
      $oneid = $one->id;
    
      print "set exire to 3 seconds\n";
    }
    
    for my $loop ( 1 .. 4 ) {
      sleep 1;
      my $bob = CGI::Session->load($oneid) or die CGI::Session->errstr;
      print "one second later $bob / $oneid load\n";
    }
    
    for my $loop ( 1 .. 4 ) {
      sleep 2;
      my $bob = CGI::Session->load($oneid) or die CGI::Session->errstr;
      print "two seconds later ";
      if ( $bob->is_expired ) {
        print "$bob / $oneid is_expired\n";
      } else {
        print "var=", $bob->param('var'), "\n";
      }
    } ## end for my $loop ( 1 .. 4 )
    
    {
      sleep 3;
      my $bob = CGI::Session->load($oneid) or die CGI::Session->errstr;
      print "three seconds later  ";
      if ( $bob->is_expired ) {
        print "$bob / $oneid is_expired\n";
      } else {
        print "var=", $bob->param('var'), "\n";
      }
    }
    
    __END__
    
    
    
    set exire to 3 seconds
    one second later CGI::Session=HASH(0xa965fc) / cf27e3ec9ff5a06a5bef4491e830c8b6 load
    one second later CGI::Session=HASH(0x97a164) / cf27e3ec9ff5a06a5bef4491e830c8b6 load
    one second later CGI::Session=HASH(0xbef68c) / cf27e3ec9ff5a06a5bef4491e830c8b6 load
    one second later CGI::Session=HASH(0xbef56c) / cf27e3ec9ff5a06a5bef4491e830c8b6 load
    two seconds later var=value
    two seconds later var=value
    two seconds later var=value
    two seconds later var=value
    three seconds later  CGI::Session=HASH(0xa965ec) / cf27e3ec9ff5a06a5bef4491e830c8b6 is_expired