Claude
63d2611b9a
Desktop had no LocationPreviewMap, so place pages, location hints, geocache details and relay groups drew an empty space there. DesktopLocationPreviewMap lays OpenStreetMap tiles out in Compose around the point, with Android's pin and tile filters (dimmed in dark mode, muted in light), drag to pan, zoom buttons and the attribution the tile policy asks for. Tiles load through the app's Coil loader, so they carry its User-Agent, share the image disk cache and follow the Tor setting. The mouse wheel stays with the page. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01L6uRu9uwMwFe2L5b97cRxF
4.2 KiB
Decentralized List items: three tiers of rendering
Status: implemented 2026-10-15. Port of Brainstorm-UI's ADR 0004 ("renderers read the governing concept") and ADR 0007 ("three tiers of item rendering").
The tiers
- Raw. No definition could be read, or it declares no fields: the item's tags as they are
(
DListItemView.defined == false,undeclared). A feed card still guesses a title fromname/title/tand a Tapestry tag element's JSON content. - Dynamic. Every concept gets this from its governing definition: field declarations,
field-type, display hints (title,summary,image,link,media,location,fact) and URL templates (["link", <template id>, <relay>, <placeholder>, <field>, …]). Fields nothing shows fold into "More fields", with undeclared tags apart. - Custom. A view made by hand for one community concept, keyed by the community concept's
coordinate (
DListConceptView): GitHub accounts, food and drink places, books. It reads values only through the governing definition and says whether itapplies; when it doesn't, the item is drawn the tier-two way. Among many (feeds, a header's item rows) a view only changes how the item reads (present: a GitHub avatar, a book's portrait cover). Its full view is drawn on the item's own page, the thread view (RenderDListItem(isPage = true)).
Tier two names no concept. Remove an entry from DListConceptView and its items read the
tier-two way everywhere.
Where it lives
| What | Where |
|---|---|
| Header/item reading, hints, media, geohash | commons/…/decentralizedLists/DListPresentation.kt |
| URL templates and their safety rules | commons/…/decentralizedLists/LinkTemplates.kt |
| Governing definition and agreement | commons/…/decentralizedLists/ConceptResolution.kt |
| Tier-three registry and readers | commons/…/decentralizedLists/tiers/ |
| Shared Compose parts, resolution in composition | commonsUI/…/ui/note/types/dlists/DListParts.kt |
| The card (tiers one and two) and dispatch | commonsUI/…/ui/note/types/dlists/DList.kt |
| Tier-three views | commonsUI/…/ui/note/types/dlists/tiers/ |
Which definition governs
The item's z names a header. That header's b names its community concept (a header that
points at itself, or at nothing, is its own community). The first of these governs: the reader's
copy (39998:<reader>:<community d>), their Tapestry Assistant's copy (the assistant from
their kind-10040), the community header, then the header the item named. A candidate counts only
when its b points at the community concept. Never by timestamp. Brainstorm's "house" tier is
Brainstorm's own account and has no counterpart here.
Staying current
Every header the card reads (listed, community, the reader's and Assistant's copies) and every
URL template goes through observeNoteEvent, so a version that reaches LocalCache redraws the
card. EventFinder's watcher also asks, while an addressable is on screen, for newer versions of
it (filterNewVersionsOfAddresses, the loader's own grouping: per kind and author, #d chunked,
plain replaceables by author, since the watcher's last EOSE), on the author's write relays and
where it was seen. This applies to every addressable rendered, not only D-lists. The reader's
Assistant comes from their kind 10040's flow, so it changes in place too.
Left out, and why
Brainstorm's tier-three pages also fetch third-party data (GitHub's account facts and repositories, Open Library's description and rating, a website's preview picture) through a same-origin proxy, so readers never contact those sites. Amethyst has no such proxy, so none of it is fetched: the views show what the item says. Reviews, recommendations and web-of-trust endorsements on places and books are also not ported.
Maps use the platform's LocationPreviewMap: osmdroid with OpenStreetMap tiles on Android, and on
desktop DesktopLocationPreviewMap, OSM tiles laid out in Compose and loaded through the app's Coil
loader (its User-Agent, disk cache and Tor routing), with the same tile filters and pin as Android.
A place's own page shows it outright, as Brainstorm's does; a tier-two item with a location
shows it only when the reader asks, so a card contacts no tile server by itself.