Cache Invalidation and SWR
Balance perceived performance and correctness with stale-while-revalidate flows.
Pattern level: macro
TL;DR
Serve cached content instantly, then revalidate in background with precise invalidation keys.
Decision criteria
- High-read products benefit from SWR defaults.
- Mutation-heavy surfaces need focused invalidation paths.
Testing + Accessibility Rubric
| Category | Level | Requirement | Done When |
|---|---|---|---|
| functional | unit | State transitions handle loading, success, empty, and error. | Reducer/state machine tests cover all transitions. |
| functional | integration | Client correctly maps API contracts into UI-ready view models. | Contract fixtures pass with no runtime shape mismatch. |
| a11y | integration | Full keyboard flow works for primary interaction loop. | Tab/Shift+Tab/Enter/Escape scenarios pass for critical controls. |
| a11y | e2e | Dynamic updates expose meaningful live region announcements. | Manual SR checks validate announcement timing and text quality. |