List-view covers, pre-warm + scroller memory fix (requires #676) by Paelsmoessan · Pull Request #731 · Listenarrs/Listenarr

Paelsmoessan · 2026-07-04T16:09:31Z

Requires #676 (prerequisite)

This PR builds on @s3ntin3l8's list-view virtual-scroller fix (#676) and needs it to work, #676 should land first. Our changes sit on top of Björn's scroller rather than replacing it.

Summary

On top of #676:

Cover thumbnails + background pre-warm — covers are generated/cached ahead of time, so scrolling doesn't fire a burst of on-demand cover work (lower memory churn, faster first paint).
Cacheable-placeholder for missing covers — a missing cover returns a cacheable placeholder instead of an uncacheable 500 that grid views re-fire on every render pass.
Cover-metadata fallback fix — read the metadata envelope via reflection instead of dynamic (the internal anonymous type across the assembly boundary threw RuntimeBinderException → uncacheable 500). This is the original List-view covers, pre-warm + scroller memory fix (requires #676) #731 fix, retained.
Virtual-scroller memory fix — drop the visibleRange watcher whose re-measure loop leaked DOM/RAM over a session on large libraries. Row height is measured on mount / resize / view-mode change / details toggle instead.

Notes

Scroll-position preservation (remembering scroll on list ↔ detail) was attempted and dropped, it was too flaky to ship reliably.
This hand-rolled .vue scroller works well enough now, but has a ceiling on very large libraries. A virtualization rewrite (TanStack Virtual) has been prototyped and may be pursued separately in a fork; this PR keeps the existing scroller and just stops the freeze/leak.

Testing

Verified locally on a large library: scrolling is smooth, RAM holds steady over a session, and covers pre-warm.

…dling Per PR Listenarrs#733 review (therobbiedavis): avoid juggling a second DB. Remove the IImageCacheStore / ImageCacheStore sidecar SQLite negative cache and its DI registration, and strip the negative-cache logic from ImagesController. The user-visible re-fetch hammering it was meant to prevent is already handled without it: the Listenarrs#731 render-loop fix stops the grid re-issuing image requests at rest, and a cover miss now returns a cacheable placeholder (Cache-Control: public, max-age=300) instead of the old uncacheable 500, so the browser stops re-asking. The only thing dropped is the server-side skip of provider re-lookups for known-coverless items, which is minor now that the loop and 500 are fixed. Thumbnails, the getImageUrl size fix, and the pre-warm service are unaffected. Build clean, 19/19 image tests pass. TODO.md: record the two follow-ups surfaced in review, canonical cover identity (hash/entity-id keying instead of ASIN) and an oversized-thumbnail byte guard. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Paelsmoessan · 2026-07-05T11:44:24Z

Heads up, I just found #676 (closing #675) by @s3ntin3l8, opened a few weeks before this PR, and it fixes the same AudiobooksView.vue virtual-scroller loop that the first half of this PR addresses. I hit the root cause independently and didn't see his PR at the time, credit for spotting and fixing it first goes to him.

His #676 is actually the more complete scroller fix: it also handles the oversized scroll area, overscroll past both ends, the unreachable last row, and header height in totalHeight, plus dedicated Vitest coverage. This PR's scroller change overlaps with it (both touch the shared measuredRowHeight / visibleRange measurement path, so they'd also conflict).

Where this PR doesn't overlap is the second fix: the cover-metadata fallback returning uncacheable 500s (an internal anonymous type read via dynamic throwing RuntimeBinderException, so those covers re-fetched on every render). #676 doesn't touch that.

Happy to consolidate whichever way you'd prefer:

rebase this PR down to just the cover-500 fix and let fix(library): stabilize list-view virtual scroller (#675) #676 own the scroller, or
fold both into one credited change if that's easier to review.

Mainly flagging so the effort isn't duplicated and #676 gets a look, it's been open and unreviewed for a few weeks.

therobbiedavis · 2026-07-05T19:52:42Z

@Paelsmoessan Agreed, split these changes. #676 will own the virtual-scroller fix and #675. Remove AudiobooksView.vue from this PR and retain only the cover-metadata fallback fix and its tests.

`GetMetadataAsync` returns `Task<object?>` and, on success, an *internal* anonymous type `new { metadata = ... }` declared in listenarr.application. The controller read it via `dynamic env.metadata`; because the anonymous type is internal to another assembly, the dynamic binder sees it as `object` and throws RuntimeBinderException ("'object' does not contain a definition for 'metadata'"), so this fallback never resolved those covers and always 500'd. Browsers don't cache 500s, so grid views re-fired them on every render pass. Fix: read the property via reflection, which reaches public members across the assembly boundary; a genuinely absent member yields null and falls through to the cacheable placeholder. Adds a controller test proving the anonymous envelope resolves (the image URL is fetched) and that a missing member no longer 500s. Per maintainer review on Listenarrs#731: the AudiobooksView virtual-scroller fix is split out (Listenarrs#676 owns it); this PR now contains only the cover-metadata fallback fix and its test. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

New CoverThumbnailService downscales cached originals to allow-listed sizes (grid=400px, grid2x=800px) on demand, caches them under config/cache/images/thumbs/, and serves them via ImagesController when ?size= is passed. Frontend getImageUrl / getProtectedImageSrc gain an optional size option (backend image URLs only). Cuts grid cover payloads from MBs to ~30KB. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

… 500s The grid's custom virtual scroller re-measured row height inside a watcher that then called updateVisibleRange() (which writes visibleRange), forming an infinite measure->update loop when card heights vary. Removed that self-retrigger; row height is measured on mount/resize/view-mode/details instead. ImageCandidateLookupWorkflow used `dynamic env.metadata`, throwing RuntimeBinderException (=> 500, uncacheable) for covers whose envelope lacks a metadata property, so every render pass re-fetched them. Replaced with safe reflection so misses fall through to the cacheable placeholder. Also wires the library grid to request ?size=grid thumbnails. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

…test The cover-thumbnail commit made ICoverThumbnailService a required 9th ctor arg on ImagesController, breaking 10 existing image tests that use the 8-arg form. Make it an optional parameter (DI still injects the registered service; ActivatorUtilities resolves it over the default). Also correct the ImageCandidateLookupWorkflow comment to the real root cause (internal anonymous type + cross-assembly dynamic, not a missing property) and add ImagesController_MetadataEnvelopeReflectionTests proving the anonymous-envelope fallback now resolves the cover via reflection and no longer 500s. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Book covers are stored as already-built /api/.../images/{id} paths, which matched none of getImageUrl's buildApiImageUrl branches, so the ?size= param was never appended and the grid fetched full-size originals. Append the size in the passthrough branch when the URL targets the images endpoint. Cuts grid cover payloads from ~530KB to ~37KB. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Dedicated SQLite index (config/cache/images/ImageCache.db) beside listenarr.db — no EF migration, rebuildable. ImagesController consults it before provider lookups: a known 'no-cover' result (re- checked after 23h) returns the cacheable placeholder immediately instead of re-hitting Audible/ Audnexus on every refresh; resolutions are recorded. ICoverThumbnailService/IImageCacheStore are optional ctor params so existing 8-arg image tests still compile. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

CoverThumbnailWarmupService pre-generates grid thumbnails for all library covers on startup (1 min after boot) and every 12h, throttled to 3 concurrent ImageSharp decodes. Idempotent — fresh thumbnails are skipped. Removes the on-demand generation lag on first library load; covers are ready on disk before the page is opened. Verified: regenerated deleted thumbnails in ~7s with no browser involved. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Sidebar sub-items (.nav-subitem) had CSS for only their default and active states, so they never highlighted on hover or keyboard focus. On top of that, .nav-sub was collapsed with pointer-events:none until opened via a parent hover, so a non-active section's children were unreachable until you hovered the top node first. Add a :hover / :focus-visible highlight, and keep the sub-navs expanded so children are always interactive and highlight on their own hover. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

…dling Per PR Listenarrs#733 review (therobbiedavis): avoid juggling a second DB. Remove the IImageCacheStore / ImageCacheStore sidecar SQLite negative cache and its DI registration, and strip the negative-cache logic from ImagesController. The user-visible re-fetch hammering it was meant to prevent is already handled without it: the Listenarrs#731 render-loop fix stops the grid re-issuing image requests at rest, and a cover miss now returns a cacheable placeholder (Cache-Control: public, max-age=300) instead of the old uncacheable 500, so the browser stops re-asking. The only thing dropped is the server-side skip of provider re-lookups for known-coverless items, which is minor now that the loop and 500 are fixed. Thumbnails, the getImageUrl size fix, and the pre-warm service are unaffected. Build clean, 19/19 image tests pass. TODO.md: record the two follow-ups surfaced in review, canonical cover identity (hash/entity-id keying instead of ASIN) and an oversized-thumbnail byte guard. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Adopts Bjorn Hansen's list-view scroller fix (upstream PR Listenarrs#676, closing Listenarrs#675): fixed list-row heights, rAF-throttled scroll handler, measure-grid-once instead of per-scroll re-measure, header height reserved in totalHeight, and overscroll clamping. This supersedes our earlier freeze fix (52d0299) with a more complete approach, and fixes the last-row text clipping our version had. REQUIRES upstream PR Listenarrs#676. Carried in canary until that PR merges upstream; the next upstream sync will reconcile it automatically. Our cover-thumbnail (?size=grid) changes in the same file are preserved. Co-Authored-By: s3ntin3l8 <58235613+s3ntin3l8@users.noreply.github.com> Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Return to the Audiobooks list after viewing a book/author/series and land back at your previous scroll position instead of the top. Two scroll models, handled natively: - Authors/series scroll the window: a router scrollBehavior restores savedPosition on back/forward and scrolls to top on forward nav (also fixes detail pages opening at the list's scroll offset). - Books scroll an inner container: save/restore scrollContainer.scrollTop across the remount (reliable now that Listenarrs#676 made row heights deterministic). - Silent background refresh on return so the remount does not flash a spinner. No keep-alive (deliberately): the view remounts, so there is a brief render-then- restore jump. That is the robust trade-off; keep-alive removes the jump but reintroduces the route-watcher nav-hijack complexity (see reason-notes). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Wrap the list view in <KeepAlive> so authors/series (a non-virtualized grouped view) no longer re-render every cover on back-out. The blocker that broke earlier keep-alive attempts was AudiobooksView's route.query.group watcher calling router.replace('/audiobooks') while cached-but-inactive, which hijacked every detail click back to the list; now guarded to run only on the active list route. - App.vue: <KeepAlive :include=['AudiobooksView']> (no key, no transition). - Watcher guard: bail unless route.name is the list route (audiobooks/home). - Lifecycle moved to onActivated/onDeactivated (the view no longer remounts): save/restore books inner scroll, silent background refresh, click-listener guard. Builds on the scrollBehavior + manual-restore scroll preservation. Known minor: the cold first view can land ~2 rows high because grouped-view covers load after the restore (layout shift); to be polished by reserving cover box size. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

…ack-out)" This reverts commit 502a2c8.

…sibleRange watcher (RAM bleed)

Paelsmoessan requested a review from a team July 4, 2026 16:09

Paelsmoessan force-pushed the fix/audiobooks-freeze branch from 365288e to 71bffc7 Compare July 4, 2026 16:44

Paelsmoessan mentioned this pull request Jul 4, 2026

Persistent cover cache: thumbnails + negative cache + pre-warm (prototype for #732) #733

Draft

Paelsmoessan force-pushed the fix/audiobooks-freeze branch from 71bffc7 to 015145c Compare July 6, 2026 18:10

Paelsmoessan changed the title ~~Fix AudiobooksView freeze/leak and uncacheable cover 500s~~ Fix broken cover-metadata fallback (uncacheable cover 500s) Jul 6, 2026

Paelsmoessan force-pushed the fix/audiobooks-freeze branch from 015145c to e014b82 Compare July 6, 2026 19:18

Paelsmoessan changed the title ~~Fix broken cover-metadata fallback (uncacheable cover 500s)~~ List-view covers, pre-warm + memory fixes (requires #676) Jul 6, 2026

Paelsmoessan and others added 15 commits July 6, 2026 21:24

Revert "Keep AudiobooksView alive across detail navigation (instant b…

7e8316f

…ack-out)" This reverts commit 502a2c8.

Remove fork-local TODO.md from PR

349d79b

Drop scroll-position preservation (flaky); keep Listenarrs#676 scroller

acff411

Reapply Listenarrs#731 leak fix on top of Listenarrs#676: drop the vi…

eef3be3

…sibleRange watcher (RAM bleed)

Paelsmoessan force-pushed the fix/audiobooks-freeze branch from e014b82 to eef3be3 Compare July 6, 2026 19:57

Paelsmoessan changed the title ~~List-view covers, pre-warm + memory fixes (requires #676)~~ List-view covers, pre-warm + scroller memory fix (requires #676) Jul 6, 2026

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Uh oh!

List-view covers, pre-warm + scroller memory fix (requires #676)#731

List-view covers, pre-warm + scroller memory fix (requires #676)#731
Paelsmoessan wants to merge 15 commits into
Listenarrs:canaryfrom
Paelsmoessan:fix/audiobooks-freeze

Paelsmoessan commented Jul 4, 2026 •

edited

Loading

Uh oh!

Paelsmoessan commented Jul 5, 2026

Uh oh!

therobbiedavis commented Jul 5, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

Uh oh!

Uh oh!

Conversation

Paelsmoessan commented Jul 4, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Requires #676 (prerequisite)

Summary

Notes

Testing

Uh oh!

Paelsmoessan commented Jul 5, 2026

Uh oh!

therobbiedavis commented Jul 5, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

Paelsmoessan commented Jul 4, 2026 •

edited

Loading