Chat feature for web app

All details available in google docs project brief. A summary is below: TECHNICAL OUTLINE: Authentication & Session Management Each call to the chat server must be accompanied with a valid session token It must only be possible for the web application (chat client) to obtain a session token A session must expire after a configurable period of inactivity User Sign-in A chat user must "sign-in” to the server to become “available" to join a chat It must only be possible for the web application (chat client) to sign-in a user A user sign-in request must consist of a minimum of name and IP address A user must be automatically set to “unavailable” status after a configurable period of inactivity Chats The client must be able to start a chat between two users A chat must be automatically expire after a configurable period of inactivity Admin View active chats View chat messages Mark a chat as “favourite" Data Retention Move chats to Mongo as one document upon expiry Some suggested REST/JSON endpoints of the server are provided below POST /session Get session token for client POST /signin Sign-in a user GET /users/?available=true/false Get a list of users with an optional boolean filter GET /chats Get chats in progress POST /chats Create new chat GET /chats/{id} Get specific chat in progress by chat identifier The same URL (with scheme ws:// instead of http://) can be used for the WebSocket connection OTHER FEATURES: - Canned Messages, Internal Link Sending, Statistics, User Surveys, Chat Status Indication & Countdowns.