LuisSanchez opened a new pull request, #36486: URL: https://github.com/apache/superset/pull/36486
### SUMMARY Optimized `TimezoneSelector` to fix a ~550ms delay when opening the Schedule panel in the Alert creation modal. Timezone data now loads on demand when the user opens the dropdown, with a loading indicator. ### BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF ## Before https://github.com/user-attachments/assets/712abe50-973a-403e-8141-9096554fefd7 ## After https://github.com/user-attachments/assets/b22d86bf-efea-42ce-afcf-fccd9a432c0a ### TESTING INSTRUCTIONS 1. Create an alert or report. 2. Click to open the Schedule section of the modal. ### Details on the refactor ### Performance - Lazy loading: timezone options load only when the dropdown opens (via `onOpenChange`) - Async computation: uses `queueMicrotask`/`setTimeout(0)` to avoid blocking the main thread - Global caching: computed options are cached for subsequent renders ### UX - Loading indicator: shows spinner and "Loading timezones..." while data loads - Dropdown stability: added `minHeight: 265px` to prevent repositioning after data loads - Conditional value: only sets the selected value after options are loaded ### Code quality - Extracted helper functions (`getOffsetKey`, `getTimezoneDisplayName`, `findMatchingTimezone`) - Reorganized file structure: types → constants → helpers → component - Removed code duplication and improved readability ### Testing - Updated tests to handle async loading behavior - Fixed DST test to correctly verify timezone formatting ## Impact - Schedule panel opens instantly (0ms delay) - Timezone dropdown shows loading state during computation (~150ms, only on first open) - Subsequent opens are instant (cached) - No functionality changes, only performance improvements ### ADDITIONAL INFORMATION <!--- Check any relevant boxes with "x" --> <!--- HINT: Include "Fixes #nnn" if you are fixing an existing issue --> - [x] Has associated issue: - [ ] Required feature flags: - [ ] Changes UI - [ ] Includes DB Migration (follow approval process in [SIP-59](https://github.com/apache/superset/issues/13351)) - [ ] Migration is atomic, supports rollback & is backwards-compatible - [ ] Confirm DB migration upgrade and downgrade tested - [ ] Runtime estimates and downtime expectations provided - [ ] Introduces new feature or API - [ ] Removes existing feature or API -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
