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fix(chapters): cache the chapters sidebar with a 10-minute TTL - #2994
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olleolleolle merged 2 commits intoOct 11, 2026
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The sidebar fragment was cached under a fixed key while the Chapter callbacks deleted a different key, so the homepage kept rendering deactivated chapters for any write path, including direct database updates. Cache the fragment under a versioned key with a 10-minute TTL instead: every write path shows up within the TTL, and a warm cache hit runs no chapter query. Fixes codebar#2993
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Side-steps the "cache expiration is difficult" problem using a TTL. Good!
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Problem: the homepage chapter list kept deactivated chapters. The sidebar fragment is cached under
views/chapters_sidebar_component/chapters-sidebar, whileChapter#expire_chapters_sidebar_cachedeletedchapters-sidebar. The delete never matched, so no write path invalidated the fragment, and production served one stale entry from 13 September to 7 October. Fixes #2993.Changes:
expires_in: 10.minutes, the shape used by the events/past fragment. Every write path, including direct database updates, shows up within the TTL. Thev2tag keeps the key clear of the stale production entry.chaptersrelation stays lazy and the cache block never enumerates it on a hit. The request spec pins this with a zero-query assertion.Chaptercache-expiry callbacks and their model specs; the TTL replaces them.Post-deploy: no cache purge needed, and chapter changes appear within 10 minutes.