/subscribe_action
subscribe action

Sourcecode in Site/actions.js:
1:   function subscribe_action() {
2:      // create a new member-object and add it to membership-mountpoint
3:      this.members.add(new Membership(session.user));
4:      res.message = new Message("subscriptionCreate", this.title);
5:      res.redirect(this.href());
6:      return;
7:   }