Design Auction Platform Channel Architecture and State Management

Context

You are starting a new real-time auction platform built on PubNub. Before implementing bidding logic, you need to establish the foundational channel architecture and auction state management. The platform will support multiple concurrent auctions, administrative controls, personal notifications, and browsable auction listings.

The platform needs clearly separated concerns: live bidding data, historical activity, administrative operations, and user-facing catalog browsing should each have appropriate communication paths. Auctions progress through multiple phases from creation to completion.

Task

Design and implement the channel naming architecture and auction lifecycle management for the platform. Define the channel structure that supports all platform communication needs, and implement the server-side countdown broadcast logic that adapts its behavior based on the current phase of the auction. Include functions for transitioning auctions between lifecycle phases.

Expected Outputs

• A complete channel naming scheme covering bid updates, activity feeds, admin operations, catalog browsing, and personal notifications
• An auction lifecycle definition with all valid states and transitions
• Server-side countdown broadcast implementation that varies behavior based on auction phase
• Functions for creating, starting, and managing auctions through their lifecycle