Lobby and Matchmaking real-time notifications
Overview
The Matchmaking and Lobby features have built in support for real-time notifications. Notifying players of changes to Matchmaking or Lobby has never been easier, as the work to handle notifications is done for you. New APIs will allow connected clients to subscribe for notifications of Lobby and Matchmaking changes. With this addition, you'll no longer need to poll for changes to matches or lobbies.
The SDK has been designed to simplify your work. The SDK manages calls between game clients or servers and PlayFab Lobby and Matchmaking services. It handles the delivery of notifications from those services to connected clients in real time. Real-time notifications have cross-platform support, and will work anywhere PlayFab supplies a SDK. Matchmaking and Lobby can be used separately or together, and real-time notifications will work in either case. There's no support for real-time notifications without the SDK at this time. Real-time notifications aren't available as a solution for stand-alone or general use.
How do real-time notifications work
Each client maintains a single WebSocket to receive real-time notifications. When there are updates to Matchmaking or Lobby resources in the cloud, the SDK will forward notifications in real-time to all connected clients subscribed to those resources.
When a client connects to receive real-time notifications, they'll open a new WebSocket connection to receive notifications and listen for change events. When a client creates a lobby, joins a lobby, starts listening for invitations, or creates a Matchmaking ticket, the connected client will subscribe to a Lobby or Matchmaking resource to listen for changes. The client will be notified when there's an update on the resource topic they’ve subscribed to. For example, if a client has subscribed to a Lobby resource, they may be notified on change events like Player A or B has joined or left a Lobby. Matchmaking and Lobby documentation describe in more detail the operations that will power notifications.
The WebSocket connection that enables real-time notifications is also used for detecting client connectivity. This client connectivity status is used by the Lobby service to power lobby ownership management.
Shared connection support
Matchmaking and Lobby notifications have support to share a single WebSocket connection, which may be useful if you’re creating a title with couch co-op. Today, up to eight local users may share the WebSocket connection, and local players can be added or removed to that shared connection. Multiple users sharing the same connection can subscribe to topics to get notifications for Matchmaking or Lobby events for those topics.
Using the SDK
The SDK simplifies your work for cross-network and cross-platform play by handling real-time notifications for you. Notifications are sent to clients on receiving invites, joining and updating lobbies, finding matches, and more. The SDK enables cross-platform play and real-time notifications on any platform that PlayFab offers SDK support. Sending notifications to clients is automatic, and the developer doesn't have to do any work to enable notifications.