Problem/Motivation
Anything that caches data as part of the render pipeline needs to properly support:
- Cache Contexts
- Cache Tags
- Max Age
- Attached Assets
- Rendered Markup
- #cache_redirect (and placeholders) for bubbled cache contexts.
For most cases in core the #pre_render / #cache pattern is used, however there are use cases where that pattern is not enough, e.g.
1. Multiple Cache-Get / Prepare and render remainder
A number of rows can be prepared in fully, but only non-cached rows, should be prepared and rendered.
The #pre_render / #cache pattern is not enough here as they don't have any multiple support, but assume each row is rendered in a single way.
2. The internal page cache is not cache context aware and would need to implement #cache_redirect for cache context bubbling itself.
Proposed resolution
An ideal API would decouple the render caching implementation and allow to do:
<?php
$cached_rows = $this->renderCache->getMultiple($render_cache_array_keyed_by_row_id);
// ...
foreach ($rendered_rows as $row_id => &$rendered_row) {
$this->renderCache->set($rendered_row);
}
return $cached_rows + $rendered_rows;
A render_cache array is a render array with just the #cache, #attached and #markup property set.
Similarly page cache could work with render_cache_arrays for cacheGet / cacheSet.
?>Remaining tasks
- Discuss
- Move cacheSet / cacheGet / createCacheId from Renderer service to RenderCache service.
User interface changes
- None
API changes
- Renderer::getCacheableRenderArray() would move the RenderCacheService::getCacheableRenderArray()