List of all logged in users in Meteor (auth branch)

[elgreg]

In my quest to build a Meteor chatroom, a feature I'd like to have is a list of current users in a given room. I'd also like to be able to say if those users are idle.

I have a function that sets the current room for a user and I could obviously use that to update a list of users in that room. But I'm not sure how to update that list on logout and I'm also interested in having a console that would alert all users when a new user logs in, show when users log out, and show when they go idle.

The idle part makes me think that I'd need to hook into the sockets the users are connected to to find when they go idle.

I tried futzing around with a registerLoginHandler in my server-side code (including at Meteor.startup), but don't seem to see mine getting called. Does this mean I'd have to bundle a package?

I'd appreciate any suggestions folks might have - felt like this was a little too broad for SO.

[Iain Shigeoka]

The only way you can do it from the application level is to implement a heartbeat (client code calls a server method every x seconds to indicate to the server the client is still online). The server can review the list of connected clients and indicate a client is offline when it fails to report in for it's scheduled heartbeat ping. You'll want to make the heartbeat long enough that you don't kick off users with long latency times and to limit the amount of traffic and connection management the server has to do. If you're willing to dig into the core, I would guess that DDP (and live data) probably maintain their own heartbeat so you should be able to hook into that - I'm not familiar enough with the core to suggest where to start though. Good luck.

-iain

[steeve]

I had to figure this out as well but not so much for chat or rooms but more so for more fine grained control over user accounts, who is online and what they can or can't do based on date/time.  The principles are the same.

Create a boolean field loggedIn on the user record OR have a separate collection of logged in users (logged_in_users or something).

In order to do this, I had to create a preLogin and postLogin hook on auth branch.  So, I created PR 270

https://github.com/meteor/meteor/pull/270

I needed to know about the user login attempt either before or after login.  Specifically in my case, I have another field on the user record called active (boolean) because my application needs the ability to activate/deactivate users and prevent them from logging in rather than just deleting/removing them.

So, unfortunately my solution relies on the PR 270 I built.  A little self serving nudge for votes for my PR on the auth branch ;).  But it works and will help solve your problem in a more Meteor oriented way of using collections and publishing and subscribing.

First, I make sure their account is active. Which is a field they cannot update themselves only Administrators can.  This is a field I added to the users collection and is not part of Meteor right now.  I found it important to have active/inactive user accounts instead of relying on removing/deleting accounts.  According to the Meteor docs and comments on the auth branch docs they suggest we feel free to add fields to the user records aka extras.  

This is in my code now and prevents user logins unless the account is active.  This checks sessions that are resuming where the user is already logged in.  It is important to understand the Meteor auth branch session resume functionality, which is why I built this hook.

Meteor.accounts.preLogin(function(options){

  if(options.resume){

    var loginToken = Meteor.accounts._loginTokens.findOne({_id: options.resume});

    if (loginToken){

      if(!Meteor.users.findOne({_id: loginToken.userId, active: true})){

        return false;

      } else {

        // Maybe update that they are back online and what rooms they are in

        // Great way to welcome them back, could even show them what happened while they were gone.

    }

  } 

  return true;

});

Second, I also check it on postLogin which is where you can decide how you want to keep track of your list of logged in users.

This is in my code now and also  prevents login unless the account is active.

Meteor.accounts.postLogin(function(result){

  if(!Meteor.users.findOne({_id: result.id, active: true})){

    return false;

  } else {

    // SET user field to loggedIn = true or put in Collection of say logged_in_users or something

    return true;

  }

});

At some point I am going to have to look at automatic timed log out server side.  And also at some point look at a notification hook for client log out.  Both are needed in auth branch.  I just haven't gotten to that point in my application yet.

If you did the logged_in_users as a separate collection of logged in users and published it then you wouldn't have to risk publishing all Meteor.users data to all clients.  You could then publish say just name and _id and maybe a subfield collection of rooms they are current in (if they can be in more room than one).  This would allow you to do private messages/1 on 1 chat as well in addition to room chat.  You could let users go invisible and such.  And since it would be published to all logged in users, it would meteormagically update and everyone would know where everyone else is at any moment.  You could still limit message delivery to room subscriptions to keep data wire transfer down.

If you fiddle around with a logout hook or a server side timed hook that auto-logs out users please keep me notified.  I am going to need that at some point myself.

Hope this helps a bit.

Steeve

[elgreg]

Thanks so much for the replies. Very helpful. I'll be implementing later this week and will let you know how it goes!

[Andrew Mao]

I've implemented this for online/offline users:

https://github.com/mizzao/meteor-user-status

Will be adding an idle state as well, similar to the feature you needed. How did your implementation go?

On Saturday, August 25, 2012 12:13:10 AM UTC-4, elgreg wrote: