Who is online, really?

Posted by Eric Stewart Thu, 15 Dec 2005 16:53:00 GMT

Courtenay was pondering today how to figure out who is online in your Rails app. I’m liking his solution better thank what I thought up on this a few days back, but since he asks….

My solution was a bit quicker and dirtier. I wanted to jump in and get a list without that oh-so-tedious (wink) process of creating a new model class. So, what I did was:

Make sure I was using ActiveRecordStore for sessions.

Just as Courtenay describes, create your sessions table:


rake create_sessions_table

But remember, I was trying to avoid an actual model class. Moving on…

Create a handy controller action

This is the meat of it. In the action I want to use to list active sessions I do something like this.

@sessions = CGI::Session::ActiveRecordStore.session_class.find(:all)
@session_pages = Paginator.new self, @sessions.size, 10, @params['page']

Of course, I was tring to be all fancy and show a paginated listing of active sessions.

Then..

Slap a nice view in

Put a nice view in and access your sessions data (in helper or rhtml template) like so:


  session.data['user'].fullname
<!- technorati tags start ->

Technorati Tags: , ,

<!- technorati tags end ->

Comments

Skip to the Comment Form | Atom feed for this post | Trackback URI

  1. Kamil Kisiel said about 5 hours later:

    Just out of curiosity, how do you handle session expiry for a case like this?

  2. Eric said about 6 hours later:

    I assume you mean filtering expired sessions from your new view.

    Since your expiry_time is in your data you still need something to load those session objects, which is really a separate problem from listing recently updated sessions.

    Since the default session table includes created_at and updated_at, I can use those just as Courtenay did still not needing a model object of my own.

    As he did, I add the following to my find call: 
     :conditions =>[ &#8216;updated_at > ?&#8217;, 
      Time.now&#8211;5.minutes ]

    That filters out sessions that haven’t been updated recently from my view. You still want a filter that updates some data within the session on regular user activity to update the “updated_at” periodically.

    All I’ve managed to do is avoid creating a separate class, though I’m in serious danger of my code breaking if something changes in the default session table/class. That’s why I mentioned in my post that I like Courtenay’s solution better.

    On the subject of cleaning out sessions, you still need a way to expire them and delete them, such as storing an expiry_time in the session data and having an action (or external script) periodically go through and delete those expired sessions.

 (leave url/email »)

   Comment Markup Help Preview comment