Replace drupal_flush_all_caches() with targeted invalidation

[jjroelofs]

Linked issues

• Fix Refactoring: replace drupal_flush_all_caches() with targeted invalidation #826

Solution

Replace drupal_flush_all_caches() with targeted cache invalidation that only clears CSS/JS aggregates, render cache, and library discovery cache. This avoids rebuilding the entire service container and router when only a CSS file has changed.

Checklist

• I have read the CONTRIBUTING.md document.
• My commit messages follow the contributing standards and style of this project.
• My code follows the coding standards and style of this project.
• Bug fix (non-breaking change which fixes an issue).
• New feature (non-breaking change which adds functionality).
• Breaking change (fix or feature that would cause existing functionality to change).
• Need to run update.php after code changes.
• Requires a change to end-user documentation.
• Requires a change to developer documentation.
• Requires a change to QA tests.
• Requires a new QA test.
• I have updated the documentation accordingly.
• All new and existing tests passed.

[jjroelofs]

Review findings:

• [P1] dxpr_theme_callbacks.inc:99: \Drupal::cache('render')->invalidateAll() only invalidates the render cache bin. It does not invalidate Drupal's rendered cache tag, so Internal Page Cache/Dynamic Page Cache can keep serving cached HTML with old CSS asset links, especially from post-update rebuilds that do not change theme config. Prefer \\Drupal\\Core\\Cache\\Cache::invalidateTags(['rendered']).\n\n- [P2] dxpr_theme_callbacks.inc:95: the replacement no longer resets asset.query_string. When aggregation is disabled, the generated themesettings-$theme.css URL remains the same, so browsers/proxies can keep the old CSS after the file is overwritten. Add \\Drupal::service('asset.query_string')->reset().\n\n- [P2] dxpr_theme_callbacks.inc:103: library.discovery->clearCachedDefinitions() is deprecated in Drupal 11.1, while this theme declares ^11 support. Use clear() when available, falling back to clearCachedDefinitions() for Drupal 9/10 compatibility.\n\nChecked GitHub CI: green. Also ran php -l on the PR version of dxpr_theme_callbacks.inc; no syntax errors.

[jjroelofs]

Thanks for narrowing the cache clear. I found two stale-cache paths that the old full flush covered and the targeted version currently misses, so I think this needs one more pass before merge.

[jjroelofs]

This targeted replacement drops the CSS/JS asset query-string reset that drupal_flush_all_caches() performed (_drupal_flush_css_js() on Drupal 9/early 10, asset.query_string->reset() on newer core). When aggregation is disabled, themesettings-*.css keeps the same URL/query suffix after the file is overwritten, so browsers or edge caches can keep serving the old CSS. Please reset the asset query string as part of this helper, with a fallback for the supported Drupal 9.3/10 range.

[jjroelofs]

Invalidating only the render bin still leaves full page/dynamic page cache responses that can contain the old asset URL or old query string. The previous full cache flush cleared those persistent bins, so anonymous users may continue to get stale CSS until those entries expire. Please also invalidate the relevant response caches/tags, or ensure the generated theme-settings CSS is represented by a cache tag that reaches cached page responses.

[jjroelofs]

Thanks for the follow-up. The asset query-string reset and page-cache invalidation concerns from the earlier review look addressed in 517dd92. I found one remaining Drupal 11 compatibility issue below.

[jjroelofs]

This still calls clearCachedDefinitions(), which is deprecated in Drupal 11.1 while this theme declares ^11 support. Please use clear() when the service provides it, falling back to clearCachedDefinitions() for Drupal 9/10 compatibility, e.g. store \Drupal::service('library.discovery') in a variable and branch with method_exists($library_discovery, 'clear').