slack-invite-server.js

Meteor.setInterval(function() {
  try {
    HTTP.get('https://slack.com/api/rtm.start', {params: {
      token: Meteor.settings.slackToken
    }}, function(err, res) {
      if (!err && res.data && res.data.users) {
        var users = res.data.users;
        var total = users.length;
        var active = _.filter(users, function(user) {
          return 'active' == user.presence;
        }).length;

        var data = {
          _id: 'slack',
          online: active,
          registered: total
        };
        // Extend data with team info.
        _.extend(data, _.pick(res.data.team, 'name', 'domain'));

        // Upsert data in Mongo.
        Slack.upsert({_id: 'slack'}, data);
      }
    });
  } catch(e) {
    console.log(e);
  }
}, 30000);

Meteor.publish('slack', function() {
  return Slack.find({_id:'slack'});
});

Meteor.methods({
  invite: function(email) {
    if (!this.isSimulation && Slack.find().count() === 1) {
      var domain = Slack.findOne().domain;

      if (domain) {
        var url = "https://" + domain + ".slack.com/api/users.admin.invite";
        var data = {
          email: email,
          token: Meteor.settings.slackToken,
          set_active: true
        };

        try {
          var data = HTTP.call("POST", url, {
            params: data
          }).data;
        } catch(e) {
          console.log(e);
        }

        return data;
      }
    }
  }
});