Explanation: transactions and session identity¶

A model's Save(ctx) needs access to persistence infrastructure. The selected design attaches a private session instead of retrieving repositories from context.Context.

Why session identity matters¶

A transaction session uses sqlc queries rebound through WithTx. A model loaded before the transaction still points to the root session.

Silently adopting the transaction would hide a major persistence boundary. Silently keeping the root session would execute outside the expected transaction. Both are unsafe.

The framework therefore assigns each session an identity and rejects cross-session associations. Models participating in a transaction must be loaded or created from the callback session.

Transaction lifecycle¶

The transaction implementation begins a driver transaction, immediately defers rollback cleanup, creates a new session over Queries.WithTx, runs the callback, and commits only on nil.

Panic cleanup is non-negotiable. Rollback registration occurs before user code runs. The panic may be rethrown after cleanup is secured.

No implicit reattachment¶

An explicit future API could clone or reload a model into another session, but the first release does not mutate a model's session behind the caller's back.