---
id: S05
parent: M001
milestone: M001
provides:
  - GET /api/v1/search — semantic search with keyword fallback
  - GET /api/v1/techniques and GET /api/v1/techniques/{slug} — technique page CRUD
  - GET /api/v1/topics and GET /api/v1/topics/{category_slug} — topic hierarchy
  - GET /api/v1/creators with sort=random|alpha|views and genre filter
  - SearchService async class for embedding+Qdrant+keyword search
  - Typed public-client.ts with all public endpoint functions
  - 6 public page components: Home, SearchResults, TechniquePage, CreatorsBrowse, CreatorDetail, TopicsBrowse
  - Complete public routing in App.tsx
requires:
  - slice: S03
    provides: Qdrant embeddings collection, technique_pages and key_moments in PostgreSQL, canonical_tags.yaml
affects:
  []
key_files:
  - backend/search_service.py
  - backend/schemas.py
  - backend/routers/search.py
  - backend/routers/techniques.py
  - backend/routers/topics.py
  - backend/routers/creators.py
  - backend/main.py
  - backend/tests/test_search.py
  - backend/tests/test_public_api.py
  - frontend/src/api/public-client.ts
  - frontend/src/pages/Home.tsx
  - frontend/src/pages/SearchResults.tsx
  - frontend/src/pages/TechniquePage.tsx
  - frontend/src/pages/CreatorsBrowse.tsx
  - frontend/src/pages/CreatorDetail.tsx
  - frontend/src/pages/TopicsBrowse.tsx
  - frontend/src/App.tsx
  - frontend/src/App.css
key_decisions:
  - D009: Async SearchService with AsyncOpenAI + AsyncQdrantClient for FastAPI request path, separate from sync pipeline clients
  - D010: R005 Search-First Web UI validated — search endpoint + frontend typeahead + grouped results
  - D011: R006 Technique Page Display validated — all sections implemented
  - D012: R007 Creators Browse Page validated — randomized default, genre filter, sort toggle
  - D013: R008 Topics Browse Page validated — two-level hierarchy with counts
  - D014: R014 Creator Equity validated — randomized default sort, equal visual weight
  - 300ms asyncio.wait_for timeout on both embedding and Qdrant calls
  - Topics endpoint loads canonical_tags.yaml at request time and counts tag matches from DB
  - Mocked SearchService at router dependency level for integration tests
  - Duplicated request<T> helper in public-client.ts to avoid coupling public and admin API clients
patterns_established:
  - Async service class pattern: create separate async client wrappers for FastAPI when sync clients exist for Celery
  - Graceful degradation pattern: embedding/Qdrant timeout → keyword ILIKE fallback with fallback_used flag
  - Typed public API client: separate from admin client, each with own request<T> helper
  - URL param-driven search: query state in URL params for shareable/bookmarkable search results
  - Router-level service mocking: patch SearchService at dependency level for clean integration tests
observability_surfaces:
  - INFO log per search query: query, scope, result_count, fallback_used, latency_ms (logger: chrysopedia.search)
  - WARNING on embedding API timeout/error with error details (300ms timeout)
  - WARNING on Qdrant search timeout/error with error details (300ms timeout)
  - fallback_used=true in SearchResponse JSON exposes degraded mode to frontend
drill_down_paths:
  - .gsd/milestones/M001/slices/S05/tasks/T01-SUMMARY.md
  - .gsd/milestones/M001/slices/S05/tasks/T02-SUMMARY.md
  - .gsd/milestones/M001/slices/S05/tasks/T03-SUMMARY.md
  - .gsd/milestones/M001/slices/S05/tasks/T04-SUMMARY.md
duration: ""
verification_result: passed
completed_at: 2026-03-30T00:19:49.898Z
blocker_discovered: false
---

# S05: Search-First Web UI

**Delivered the complete public-facing web UI: async search service with Qdrant+keyword fallback, landing page with debounced typeahead, technique page detail, creators browse (randomized default sort), topics browse (two-level hierarchy), and 18 integration tests — all 58 backend tests pass, frontend production build clean.**

## What Happened

## Summary

Slice S05 built the entire public-facing web UI layer for Chrysopedia — the search-first experience that lets a music producer find a specific technique in under 30 seconds.

### Backend (T01 + T02)

Created `SearchService` — a new async client class that wraps `openai.AsyncOpenAI` and `qdrant_client.AsyncQdrantClient` for the FastAPI request path (the existing sync clients remain for Celery pipeline tasks). The search orchestration flow: embed query text (300ms timeout) → Qdrant vector search → enrich with PostgreSQL metadata → fallback to SQL ILIKE keyword search if embedding or Qdrant fails. Input validation handles empty queries, long queries (truncated to 500 chars), and invalid scope (defaults to "all").

Four new routers mounted at `/api/v1`:
- **search** — `GET /search?q=...&scope=all|topics|creators&limit=20` with `SearchResponse` including `fallback_used` flag
- **techniques** — `GET /techniques` (list with category/creator filters, pagination) and `GET /techniques/{slug}` (full detail with eager-loaded key_moments, related links, creator info)  
- **topics** — `GET /topics` (category hierarchy with technique_count/creator_count per sub-topic from canonical_tags.yaml + DB aggregation) and `GET /topics/{category_slug}`
- **creators** (enhanced) — `sort=random` default (R014), `sort=alpha|views`, genre filter, technique_count/video_count correlated subqueries

18 integration tests added across test_search.py (5) and test_public_api.py (13), covering search happy path, empty query, keyword fallback, scope filter, techniques list/detail/404, topics hierarchy, creators random/alpha sort, genre filter, detail/404, and counts verification. All tests use real PostgreSQL with seeded data. Full suite: 58/58 pass.

### Frontend (T03 + T04)

Created `public-client.ts` with typed interfaces matching all backend schemas and 6 endpoint functions. Built 6 new page components:

- **Home** — auto-focused search bar with 300ms debounced typeahead (top 5 after 2+ chars), nav cards for Topics/Creators, Recently Added section
- **SearchResults** — URL param-driven, grouped by type (techniques first, key moments second), keyword fallback banner
- **TechniquePage** — full detail rendering: header badges/tags/creator link, amber banner for unstructured/livestream content, body_sections JSONB prose, key moments index, signal chains, plugins pills, related techniques
- **CreatorsBrowse** — randomized default sort (R014 creator equity), genre filter pills, type-to-narrow name filter, sort toggle (Random/A-Z/Views)
- **CreatorDetail** — creator info header + technique pages filtered by creator_slug
- **TopicsBrowse** — two-level expandable hierarchy (6 categories from canonical_tags.yaml), sub-topic counts, filter input

All 9 routes registered in App.tsx (6 public + 2 admin + catch-all). Updated navigation header with "Chrysopedia" branding and links to Home/Topics/Creators/Admin. ~500 lines of CSS added. TypeScript strict compilation passes with zero errors. Production build: 43 modules, 199KB JS gzipped to 62KB.

### Observability

- Search endpoint logs at INFO: query, scope, result_count, fallback_used, latency_ms
- Embedding/Qdrant failures logged at WARNING with error details and timeout information
- `fallback_used=true` in search response exposes degraded search mode to the UI

## Verification

**Backend Verification:**
- `cd backend && python -c "from search_service import SearchService; print('OK')"` → ✅ imports clean
- `cd backend && python -c "from routers.search import router; print(router.routes)"` → ✅ 1 route
- `cd backend && python -c "from routers.techniques import router; print(router.routes)"` → ✅ 2 routes
- `cd backend && python -c "from routers.topics import router; print(router.routes)"` → ✅ 2 routes
- `cd backend && python -c "from main import app; routes=[r.path for r in app.routes]; print([r for r in routes if 'api' in r])"` → ✅ 21 API routes including /api/v1/search, /api/v1/techniques, /api/v1/topics
- `cd backend && python -m pytest tests/ -v` → ✅ 58/58 pass (40 existing + 18 new, 139.74s)

**Frontend Verification:**
- `cd frontend && npx tsc -b` → ✅ zero TypeScript errors
- `cd frontend && npm run build` → ✅ 43 modules, 773ms build, 199KB JS
- All 6 page files exist: Home.tsx, SearchResults.tsx, TechniquePage.tsx, CreatorsBrowse.tsx, CreatorDetail.tsx, TopicsBrowse.tsx
- All 9 routes registered in App.tsx

## Requirements Advanced

- R015 — Search infrastructure (async Qdrant + debounced typeahead + technique page routing) architecturally supports <30s retrieval; requires runtime validation with real data

## Requirements Validated

- R005 — Search endpoint with async embedding + Qdrant + keyword fallback, frontend typeahead, grouped results. 5 integration tests pass.
- R006 — TechniquePage.tsx renders all sections: header/badges/prose/key moments/signal chains/plugins/related links. Backend detail endpoint with eager-loaded data.
- R007 — CreatorsBrowse with genre filter, type-to-narrow, sort toggle (random/alpha/views). 6 integration tests for creators endpoint.
- R008 — TopicsBrowse with two-level hierarchy, expandable sub-topics with counts, filter input. Topics endpoint tested.
- R014 — CreatorsBrowse defaults to sort=random (func.random() ORDER BY). Equal visual weight in CSS. Integration test verifies.

## New Requirements Surfaced

None.

## Requirements Invalidated or Re-scoped

None.

## Deviations

- T04 added `creator_slug` param to `TechniqueListParams` in public-client.ts (not in original plan but required for CreatorDetail to fetch techniques filtered by creator)
- T02 noted CreatorDetail schema only exposes video_count (not technique_count) — CreatorBrowseItem (list) has both counts
- T04 hardcoded genre list from canonical_tags.yaml rather than fetching dynamically
- T04 set all topic categories expanded by default for discoverability

## Known Limitations

- CreatorDetail endpoint returns video_count but not technique_count (the list endpoint's CreatorBrowseItem has both)
- Genre list for filter pills is hardcoded in frontend rather than fetched from backend
- Topic categories are all expanded by default (no collapsed-by-default state)
- Search latency target (<500ms) depends on embedding API and Qdrant response times — keyword fallback ensures results always arrive but with lower quality
- R015 (30-second retrieval target) is architecturally supported but requires end-to-end runtime validation with real data

## Follow-ups

None.

## Files Created/Modified

- `backend/search_service.py` — New async SearchService class: embed_query (300ms timeout), search_qdrant, keyword_search (ILIKE), orchestrated search with fallback
- `backend/schemas.py` — Added SearchResultItem, SearchResponse, TechniquePageDetail, TopicCategory, TopicSubTopic, CreatorBrowseItem schemas
- `backend/routers/search.py` — New router: GET /search with query/scope/limit params, SearchService instantiation, latency logging
- `backend/routers/techniques.py` — New router: GET /techniques (list with filters), GET /techniques/{slug} (detail with eager-loaded relations)
- `backend/routers/topics.py` — New router: GET /topics (category hierarchy from canonical_tags.yaml + DB counts), GET /topics/{category_slug}
- `backend/routers/creators.py` — Enhanced: sort=random|alpha|views, genre filter, technique_count/video_count correlated subqueries
- `backend/main.py` — Mounted search, techniques, topics routers at /api/v1
- `backend/tests/test_search.py` — 5 integration tests: search happy path, empty query, keyword fallback, scope filter, no results
- `backend/tests/test_public_api.py` — 13 integration tests: techniques list/detail/404, topics hierarchy, creators sort/filter/detail/404/counts
- `frontend/src/api/public-client.ts` — Typed API client with interfaces and 6 endpoint functions for all public routes
- `frontend/src/pages/Home.tsx` — Landing page: auto-focus search, 300ms debounced typeahead, nav cards, recently added
- `frontend/src/pages/SearchResults.tsx` — Search results: URL param-driven, type-grouped display, fallback banner
- `frontend/src/pages/TechniquePage.tsx` — Full technique page: header/badges/prose/key moments/signal chains/plugins/related links, amber banner
- `frontend/src/pages/CreatorsBrowse.tsx` — Creators browse: randomized default sort, genre filter pills, name filter, sort toggle
- `frontend/src/pages/CreatorDetail.tsx` — Creator detail: info header + technique pages filtered by creator_slug
- `frontend/src/pages/TopicsBrowse.tsx` — Topics browse: two-level expandable hierarchy with counts and filter input
- `frontend/src/App.tsx` — Added 6 public routes, updated navigation header with Chrysopedia branding
- `frontend/src/App.css` — ~500 lines added: search bar, typeahead, nav cards, technique page, browse pages, filter/sort controls
