Log Inventory Changes from the System’s Perspective

A share-inventory system processes client purchases and sales. Add logs that record changes from the system's perspective: for example, when a client buys one share from the system, the system log records a sale of one share. Explain where logging belongs in the transaction flow and how to keep the recorded action, quantity, and resulting inventory consistent. The underlying fractional-share execution rules and starter code are not supplied; do not invent them. ### Constraints & Assumptions - Client and system directions are opposite for a trade between them. - Quantities may be fractional, so arithmetic and formatting must preserve the agreed precision. - Clarify whether the log records attempted actions, committed inventory changes, or both. ### Clarifying Questions to Ask - Is this an audit record that must commit with inventory, or a best-effort diagnostic log? - What identifies a repeated client request and a committed trade? - How are rejected or partially completed trades represented by the existing system? ```hint Logging before a transaction commits can describe a sale that never actually happened. ``` ### What a Strong Answer Covers Define the perspective and event meaning, place logging at a reliable state boundary, and preserve stable transaction identity. Explain precision, duplicate processing, and the distinction between an attempted operation and a committed inventory effect. ### Follow-up Questions - What would a client sale look like in the system log? - How would a retry avoid creating a second audit event for the same committed trade?