perf: fetches parallèles + /api/health expose vigilance freshness

- /departement/[code] : Promise.allSettled sur les 3 fetches externes
  (vigilance MF, climato data.gouv, hourly SYNOP). Avant : ~15-20s
  sériel cold-fetch. Après : ~10s max (= temps du plus lent = climato).

- normales (3 ranges) : Promise.all aussi, économise ~30 ms.

- /api/health enrichi avec vigilance.productDatetime + ageSeconds
  pour permettre au cron freshness de checker sans /api/vigilance
  (qui a été supprimé en public).

Pré-requis pour le cron warmup côté infra repo (cf. scripts/cron-warmup-info-canicule.sh).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/pages/api/health.ts

@@ -1,22 +1,40 @@
 import type { APIRoute } from 'astro';
 import { pingCache } from '../../lib/cache';
+import { getVigilanceSnapshot } from '../../lib/vigilance';
 
 export const prerender = false;
 
+// Endpoint d'usage interne : UptimeRobot (uptime) + cron HC.io freshness.
+// Pas de CORS (pas destiné aux clients tiers).
 export const GET: APIRoute = async () => {
   const cacheOk = await pingCache();
+
+  // Best-effort : récupère le snapshot Vigilance pour exposer la fraîcheur.
+  // Si KO, on dégrade sans casser le health (l'uptime reste vert).
+  let vigilance: { productDatetime: string | null; ageSeconds: number | null } | null = null;
+  try {
+    const snap = await getVigilanceSnapshot();
+    const pd = snap.productDatetime;
+    vigilance = {
+      productDatetime: pd,
+      ageSeconds: pd ? Math.floor((Date.now() - new Date(pd).getTime()) / 1000) : null,
+    };
+  } catch {
+    vigilance = null;
+  }
+
   const body = {
     status: cacheOk ? 'ok' : 'degraded',
     cache: cacheOk,
     time: new Date().toISOString(),
+    vigilance,
   };
+
   return new Response(JSON.stringify(body), {
     status: cacheOk ? 200 : 503,
     headers: {
       'Content-Type': 'application/json',
       'Cache-Control': 'no-store',
-      // Pas de CORS : endpoint d'usage interne (UptimeRobot + cron HC.io freshness).
-      // Pas destiné aux clients tiers.
     },
   });
 };

src/pages/departement/[code].astro

@@ -23,50 +23,54 @@ if (!dept) {
 
 const drom = isDrom(dept.code);
 
+// Fetch en parallèle des 3 sources externes (vigilance MF, climato data.gouv, hourly MF SYNOP).
+// Cold-fetch climato = ~10s (4 MB de previous CSV.GZ), parallel ramène le total à max(individuel).
+const [snapshotR, climatoR, hourlyR] = drom
+  ? [Promise.resolve(null), Promise.resolve(null), Promise.resolve(null)] as const
+  : ([
+      getVigilanceSnapshot(),
+      getClimatoForDepartement(dept.code),
+      getHourlyForDepartement(dept.code, 24),
+    ] as const);
+
+const settled = await Promise.allSettled([snapshotR, climatoR, hourlyR]);
 let snapshot;
 let error: string | null = null;
-if (!drom) {
-  try {
-    snapshot = await getVigilanceSnapshot();
-  } catch (e) {
-    error = (e as Error).message;
-  }
-}
-
 let climato = null;
-let anomaly = null;
 let hourly = null;
+
+if (settled[0].status === 'fulfilled') snapshot = settled[0].value as Awaited<ReturnType<typeof getVigilanceSnapshot>> | null;
+else error = (settled[0].reason as Error).message;
+
+if (settled[1].status === 'fulfilled') climato = settled[1].value as Awaited<ReturnType<typeof getClimatoForDepartement>> | null;
+else console.warn('climato fetch failed for', dept.code, (settled[1].reason as Error).message);
+
+if (settled[2].status === 'fulfilled') hourly = settled[2].value as Awaited<ReturnType<typeof getHourlyForDepartement>> | null;
+else console.warn('hourly fetch failed for', dept.code, (settled[2].reason as Error).message);
+
+let anomaly = null;
 let normales7: Array<{ tx: number | null; tn: number | null }> = [];
 let normales30: Array<{ tx: number | null; tn: number | null }> = [];
+let normales365: Array<{ tx: number | null; tn: number | null }> = [];
 let normaleHourly: { tx: number | null; tn: number | null } | null = null;
-if (!drom) {
-  try {
-    climato = await getClimatoForDepartement(dept.code);
-    if (climato?.days?.length) {
-      anomaly = await computeAnomaly(dept.code, climato.days);
-    }
-  } catch (e) {
-    console.warn('climato fetch failed for', dept.code, (e as Error).message);
-  }
-  try {
-    hourly = await getHourlyForDepartement(dept.code, 24);
-  } catch (e) {
-    console.warn('hourly fetch failed for', dept.code, (e as Error).message);
-  }
-}
 
 const last7 = climato?.days?.slice(-7) ?? [];
 const last30 = climato?.days?.slice(-30) ?? [];
 const last365 = climato?.days?.slice(-365) ?? [];
-let normales365: Array<{ tx: number | null; tn: number | null }> = [];
 
 if (!drom) {
-  const series7 = await normalesForRange(dept.code, last7.map((d) => d.date));
+  // Tous les lookups normales sont locaux (JSON statique) — pas besoin de paralléliser plus.
-  normales7 = series7.map((n) => ({ tx: n?.tx ?? null, tn: n?.tn ?? null }));
+  if (climato?.days?.length) {
-  const series30 = await normalesForRange(dept.code, last30.map((d) => d.date));
+    anomaly = await computeAnomaly(dept.code, climato.days);
-  normales30 = series30.map((n) => ({ tx: n?.tx ?? null, tn: n?.tn ?? null }));
+  }
-  const series365 = await normalesForRange(dept.code, last365.map((d) => d.date));
+  const [s7, s30, s365] = await Promise.all([
-  normales365 = series365.map((n) => ({ tx: n?.tx ?? null, tn: n?.tn ?? null }));
+    normalesForRange(dept.code, last7.map((d) => d.date)),
+    normalesForRange(dept.code, last30.map((d) => d.date)),
+    normalesForRange(dept.code, last365.map((d) => d.date)),
+  ]);
+  normales7 = s7.map((n) => ({ tx: n?.tx ?? null, tn: n?.tn ?? null }));
+  normales30 = s30.map((n) => ({ tx: n?.tx ?? null, tn: n?.tn ?? null }));
+  normales365 = s365.map((n) => ({ tx: n?.tx ?? null, tn: n?.tn ?? null }));
   normaleHourly = await normaleForDate(dept.code, new Date());
   if (normaleHourly) normaleHourly = { tx: normaleHourly.tx, tn: normaleHourly.tn };
 }