Fix slow page loads: parallelize homepage fetches, restore caching, fix senators N+1 - #209
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…ix senators N+1 The homepage awaited getCarousel/getEvents/getFinanceHearings/getNews sequentially instead of concurrently. Several admin-editable pages had caching fully disabled (cache: "no-store" in fetchAPI, no revalidate window) so every visit re-fetched from the backend live. And the senators list endpoint issued 2 extra DB queries per senator instead of eager-loading committee memberships. - frontend/src/app/page.tsx, RecentNews.tsx: fetch homepage data via Promise.allSettled instead of sequential awaits; RecentNews is now a presentational component fed data as a prop. - frontend/src/lib/api.ts: fetchAPI takes an optional revalidateSeconds param; getStaff/getLeadership/getCommittees/getCommitteeById/ getFinanceHearings now use a 60s revalidate window instead of no-store, restoring ISR caching between admin edits. - backend/app/routers/senators.py, models/Senator.py: eager-load committee memberships via selectinload instead of querying per senator. Also fixes Senator.committee_memberships being typed as bare Mapped[list] (no type param), which made SQLAlchemy infer uselist=False and silently return a single row/None instead of a list. Closes #205
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Users reported the site sometimes takes a while to load. Investigation (issue #205) found three separate, compounding causes — a sequential fetch waterfall on the homepage, caching disabled on several admin-editable pages, and an N+1 query pattern on the senators API.
Changes:
frontend/src/app/page.tsx,RecentNews.tsx— the homepage awaitedgetCarousel(),getEvents(),getFinanceHearings(), and (via the nestedRecentNewsserver component)getNews()sequentially, meaning every visit stacked 4 backend round trips in series. Switched toPromise.allSettledso they run concurrently, and turnedRecentNewsinto a plain presentational component that receives its data as a prop instead of fetching on its own.frontend/src/lib/api.ts—fetchAPIhardcodedcache: "no-store", so admin-editable pages (staff, leadership, committees, finance hearings) re-fetched from the backend on every single request with zero caching. Added an optionalrevalidateSecondsparam and switchedgetStaff,getLeadership,getCommittees,getCommitteeById, andgetFinanceHearingsto a 60s revalidate window — admin edits still show up within a minute, but requests in between are served from cache instead of hitting the backend live.backend/app/routers/senators.py,models/Senator.py—list_senatorsissued 2 extra DB queries per senator (2N + 1total) instead of eager-loading committee memberships, unlikecommittees.py's equivalent endpoint which already usesselectinloadcorrectly. Fixed by eager-loading viaselectinloadin_base_query. This also surfaced a real bug in the model:Senator.committee_membershipswas typed as bareMapped[list](no type param), which made SQLAlchemy inferuselist=Falseand silently return a single row orNoneinstead of a list — exactly the landmine the old code's docstring said it was working around by hand-querying instead of using the relationship. Fixed the annotation toMapped[list["CommitteeMembership"]].Verified: all 588 backend tests pass,
tsc --noEmitis clean, andnext buildconfirms/about/staff,/committees,/funding/apply,/senators/leadershipflipped from fully dynamic (ƒ) to ISR (○, 1m revalidate).Closes #205