Harden serverless DB checks, CORS, cursor lifecycle, and healing JSON parse

Replace the process.env.DATABASE_URL! bang assertion across every
Vercel serverless function with an explicit check that returns 500,
removing a silent crash path. Make src/api.py CORS origins configurable
via ALLOWED_ORIGINS. Fix a cursor leak in PgConnection by closing the
previously-returned cursor before opening the next one, and add a
bulk insert_daily_readings_batch() helper using executemany. Catch
JSONDecodeError on Claude healing responses and return an empty
assessment list rather than crashing mid-heal. Update CLAUDE.md to
the new extreme-heat-insurance.jeff-levine.com custom domain.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

CLAUDE.md

@@ -6,7 +6,7 @@ Parametric heat insurance for outdoor workers in Dar es Salaam. Chronos-Bolt fou
 
 **3-tier deployment:**
 - **HF Spaces** (`jtlevine/climate-risk-engine`): Runs pipeline weekly (writes to Neon), then sleeps. Docker, FastAPI, port 7860.
-- **Vercel** (`climate-risk-engine.vercel.app`): Frontend + serverless API functions reading from Neon. Always on. Serverless functions in `frontend/api/*.ts` using `@neondatabase/serverless`.
+- **Vercel** (`https://extreme-heat-insurance.jeff-levine.com`): Frontend + serverless API functions reading from Neon. Always on. Serverless functions in `frontend/api/*.ts` using `@neondatabase/serverless`.
 - **Neon** (`withered-salad-81435132`): PostgreSQL in `aws-us-west-2`. Sync psycopg2 with SimpleConnectionPool.
 
 **Data flow:**

config.py

@@ -190,6 +190,9 @@ ZONES: list[UrbanZone] = [
               [1, 2, 8, 9], "Dense residential. Hillside construction workers, market sellers."),
 ]
 
+# Built once at import time from ZONES. If ZONES is ever mutated at runtime
+# (e.g. hot-reloaded from a new fork config), this map must be rebuilt —
+# nothing watches ZONES for changes.
 ZONE_MAP: dict[str, UrbanZone] = {z.zone_id: z for z in ZONES}
 
 # Cities for grouping

frontend/api/basis-risk.ts

@@ -2,7 +2,10 @@ import type { VercelRequest, VercelResponse } from '@vercel/node'
 import { neon } from '@neondatabase/serverless'
 
 export default async function handler(_req: VercelRequest, res: VercelResponse) {
-  const sql = neon(process.env.DATABASE_URL!)
+  if (!process.env.DATABASE_URL) {
+    return res.status(500).json({ error: 'DATABASE_URL not set' })
+  }
+  const sql = neon(process.env.DATABASE_URL)
 
   const reports = await sql`
     SELECT br.zone_id, z.name AS zone_name, z.city, z.settlement_type,

frontend/api/coverage-recommendation.ts

@@ -49,7 +49,10 @@ function getEnrollment(zone_id: string, gender: Gender, settlement_type: string,
 }
 
 export default async function handler(req: VercelRequest, res: VercelResponse) {
-  const sql = neon(process.env.DATABASE_URL!)
+  if (!process.env.DATABASE_URL) {
+    return res.status(500).json({ error: 'DATABASE_URL not set' })
+  }
+  const sql = neon(process.env.DATABASE_URL)
   const gender = (req.query.gender as Gender) || 'all'
   const settlement = (req.query.settlement as Settlement) || 'all'
 

frontend/api/disbursements.ts

@@ -14,7 +14,10 @@ const ZONE_WORKERS: Record<string, number> = {
 }
 
 export default async function handler(_req: VercelRequest, res: VercelResponse) {
-  const sql = neon(process.env.DATABASE_URL!)
+  if (!process.env.DATABASE_URL) {
+    return res.status(500).json({ error: 'DATABASE_URL not set' })
+  }
+  const sql = neon(process.env.DATABASE_URL)
 
   // Get current conditions + neural pricing for all Dar zones
   const zones = await sql`

frontend/api/enrolled-workers.ts

@@ -2,7 +2,10 @@ import type { VercelRequest, VercelResponse } from '@vercel/node'
 import { neon } from '@neondatabase/serverless'
 
 export default async function handler(_req: VercelRequest, res: VercelResponse) {
-  const sql = neon(process.env.DATABASE_URL!)
+  if (!process.env.DATABASE_URL) {
+    return res.status(500).json({ error: 'DATABASE_URL not set' })
+  }
+  const sql = neon(process.env.DATABASE_URL)
 
   const zones = await sql`
     SELECT zone_id, worker_population_est,

frontend/api/indices.ts

@@ -2,7 +2,10 @@ import type { VercelRequest, VercelResponse } from '@vercel/node'
 import { neon } from '@neondatabase/serverless'
 
 export default async function handler(_req: VercelRequest, res: VercelResponse) {
-  const sql = neon(process.env.DATABASE_URL!)
+  if (!process.env.DATABASE_URL) {
+    return res.status(500).json({ error: 'DATABASE_URL not set' })
+  }
+  const sql = neon(process.env.DATABASE_URL)
 
   // Get zones with their latest heat index + 90-day history
   const zones = await sql`SELECT DISTINCT zone_id FROM heat_indices ORDER BY zone_id`

frontend/api/notifications.ts

@@ -2,7 +2,10 @@ import type { VercelRequest, VercelResponse } from '@vercel/node'
 import { neon } from '@neondatabase/serverless'
 
 export default async function handler(_req: VercelRequest, res: VercelResponse) {
-  const sql = neon(process.env.DATABASE_URL!)
+  if (!process.env.DATABASE_URL) {
+    return res.status(500).json({ error: 'DATABASE_URL not set' })
+  }
+  const sql = neon(process.env.DATABASE_URL)
 
   const notifications = await sql`
     SELECT n.id, n.zone_id, z.name AS zone_name, z.city,

frontend/api/pipeline/runs.ts

@@ -2,7 +2,10 @@ import type { VercelRequest, VercelResponse } from '@vercel/node'
 import { neon } from '@neondatabase/serverless'
 
 export default async function handler(_req: VercelRequest, res: VercelResponse) {
-  const sql = neon(process.env.DATABASE_URL!)
+  if (!process.env.DATABASE_URL) {
+    return res.status(500).json({ error: 'DATABASE_URL not set' })
+  }
+  const sql = neon(process.env.DATABASE_URL)
 
   const runs = await sql`
     SELECT run_id, started_at, finished_at, status,

frontend/api/pipeline/stats.ts

@@ -2,7 +2,10 @@ import type { VercelRequest, VercelResponse } from '@vercel/node'
 import { neon } from '@neondatabase/serverless'
 
 export default async function handler(_req: VercelRequest, res: VercelResponse) {
-  const sql = neon(process.env.DATABASE_URL!)
+  if (!process.env.DATABASE_URL) {
+    return res.status(500).json({ error: 'DATABASE_URL not set' })
+  }
+  const sql = neon(process.env.DATABASE_URL)
 
   const [stats] = await sql`
     SELECT

frontend/api/triggers.ts

@@ -2,7 +2,10 @@ import type { VercelRequest, VercelResponse } from '@vercel/node'
 import { neon } from '@neondatabase/serverless'
 
 export default async function handler(_req: VercelRequest, res: VercelResponse) {
-  const sql = neon(process.env.DATABASE_URL!)
+  if (!process.env.DATABASE_URL) {
+    return res.status(500).json({ error: 'DATABASE_URL not set' })
+  }
+  const sql = neon(process.env.DATABASE_URL)
 
   const triggers = await sql`
     SELECT te.zone_id, z.name AS zone_name, z.city, te.trigger_level,

frontend/api/zones.ts

@@ -2,7 +2,10 @@ import type { VercelRequest, VercelResponse } from '@vercel/node'
 import { neon } from '@neondatabase/serverless'
 
 export default async function handler(_req: VercelRequest, res: VercelResponse) {
-  const sql = neon(process.env.DATABASE_URL!)
+  if (!process.env.DATABASE_URL) {
+    return res.status(500).json({ error: 'DATABASE_URL not set' })
+  }
+  const sql = neon(process.env.DATABASE_URL)
 
   const zones = await sql`
     SELECT z.zone_id, z.name, z.city, z.country, z.latitude, z.longitude,

src/api.py

@@ -76,9 +76,17 @@ async def lifespan(app: FastAPI):
 
 app = FastAPI(title="Extreme Heat Risk Engine", version="1.0.0", lifespan=lifespan)
 
+# CORS origins configurable via ALLOWED_ORIGINS (comma-separated).
+# Defaults to "*" so local dev and HF Spaces preview stay permissive.
+_allowed_origins_env = os.environ.get("ALLOWED_ORIGINS", "*").strip()
+if _allowed_origins_env == "*" or not _allowed_origins_env:
+    _allowed_origins = ["*"]
+else:
+    _allowed_origins = [o.strip() for o in _allowed_origins_env.split(",") if o.strip()]
+
 app.add_middleware(
     CORSMiddleware,
-    allow_origins=["*"],
+    allow_origins=_allowed_origins,
     allow_credentials=True,
     allow_methods=["*"],
     allow_headers=["*"],

src/database/crud.py

@@ -75,6 +75,7 @@ class PgConnection:
         self._conn = pool.getconn()
         self._conn.autocommit = True
         self._pool = pool
+        self._last_cur = None
         self._refresh_conn()
 
     def _refresh_conn(self):
@@ -93,13 +94,33 @@ class PgConnection:
             self._conn.autocommit = True
 
     def execute(self, sql: str, params=None):
-        """Execute SQL with %s placeholders. Returns cursor."""
+        """Execute SQL with %s placeholders. Returns cursor.
+
+        To avoid leaking server-side cursor resources over long-lived
+        connections (e.g. during a pipeline run with hundreds of inserts),
+        we close the previously-returned cursor before creating a new one.
+        Callers that need to keep two cursors open simultaneously must use
+        ``self._conn.cursor()`` directly.
+        """
+        if self._last_cur is not None:
+            try:
+                self._last_cur.close()
+            except Exception:
+                pass
+            self._last_cur = None
         cur = self._conn.cursor()
         cur.execute(sql, params)
+        self._last_cur = cur
         return cur
 
     def close(self):
         """Return connection to pool."""
+        if self._last_cur is not None:
+            try:
+                self._last_cur.close()
+            except Exception:
+                pass
+            self._last_cur = None
         if self._pool and self._conn:
             self._pool.putconn(self._conn)
             self._conn = None
@@ -283,6 +304,44 @@ def insert_daily_reading(conn, reading: dict) -> Optional[int]:
     return row[0] if row else None
 
 
+def insert_daily_readings_batch(conn, readings: list[dict]) -> int:
+    """Bulk-insert daily readings with a single round-trip per chunk.
+
+    Uses psycopg2's executemany (single statement, many rows). Much faster
+    than insert_daily_reading() in a loop during pipeline runs. Does not
+    return row IDs — use insert_daily_reading() if you need the ID.
+    """
+    if not readings:
+        return 0
+    rows = [
+        (r["zone_id"], _to_date(r["date"]),
+         r.get("temp_mean_c"), r.get("temp_max_c"),
+         r.get("temp_min_c"), r.get("humidity_pct"),
+         r.get("wind_speed_ms"), r.get("solar_rad_wm2"),
+         r.get("precip_mm"),
+         r.get("source", "unknown"),
+         r.get("data_quality", 0.0))
+        for r in readings
+    ]
+    cur = conn._conn.cursor()
+    try:
+        cur.executemany(
+            """
+            INSERT INTO daily_readings (zone_id, date, temp_mean_c, temp_max_c,
+                temp_min_c, humidity_pct, wind_speed_ms, solar_rad_wm2,
+                precip_mm, source, data_quality)
+            VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s)
+            ON CONFLICT (zone_id, date) DO UPDATE SET
+                temp_max_c = EXCLUDED.temp_max_c,
+                data_quality = EXCLUDED.data_quality
+            """,
+            rows,
+        )
+        return len(rows)
+    finally:
+        cur.close()
+
+
 def get_daily_readings(conn, zone_id: str, limit: int = 90) -> list[dict]:
     """Fetch recent daily readings for a zone."""
     cur = conn.execute(

src/healing/healer.py

@@ -526,14 +526,27 @@ class HealingAgent:
         return SYSTEM_PROMPT_TEMPLATE.format(n_zones=n_zones)
 
     def _parse_assessments(self, text: str) -> list[dict[str, Any]]:
-        """Extract JSON assessment array from Claude's response."""
+        """Extract JSON assessment array from Claude's response.
+
+        Claude occasionally returns malformed JSON (trailing commas, partial
+        fences, truncated output). We catch JSONDecodeError on both regex
+        groups and fall back to an empty assessment list so the pipeline
+        continues rather than crashing mid-heal.
+        """
         match = re.search(r'```json\s*([\s\S]*?)```', text)
         if match:
-            return json.loads(match.group(1))
+            try:
+                return json.loads(match.group(1))
+            except json.JSONDecodeError as exc:
+                log.warning("Failed to parse fenced JSON assessments: %s", exc)
 
         match = re.search(r'\[[\s\S]*\]', text)
         if match:
-            return json.loads(match.group(0))
+            try:
+                return json.loads(match.group(0))
+            except json.JSONDecodeError as exc:
+                log.warning("Failed to parse bracketed JSON assessments: %s", exc)
+                return []
 
         raise ValueError("Could not find JSON assessment array in response")
 

src/pipeline.py

@@ -34,6 +34,7 @@ from src.notification.sender import create_sender
 # Database CRUD (imported lazily to keep pipeline usable without DB)
 from src.database.crud import (
     insert_daily_reading,
+    insert_daily_readings_batch,
     insert_healed_reading,
     insert_healing_log,
     insert_heat_index,
@@ -254,22 +255,28 @@ class HeatRiskPipeline:
             ok_count = sum(1 for r in results if r.completeness > 0.5)
             total_readings = sum(len(r.readings) for r in results)
 
-            # DB: write daily readings
-            for r in results:
-                for reading in r.readings:
-                    self._db_write(insert_daily_reading, self.db, {
-                        "zone_id": reading.zone_id,
-                        "date": reading.date,
-                        "temp_mean_c": reading.temp_mean_c,
-                        "temp_max_c": reading.temp_max_c,
-                        "temp_min_c": reading.temp_min_c,
-                        "humidity_pct": reading.humidity_pct,
-                        "wind_speed_ms": reading.wind_speed_ms,
-                        "solar_rad_wm2": None,
-                        "precip_mm": reading.precip_mm,
-                        "source": reading.source,
-                        "data_quality": reading.data_quality,
-                    })
+            # DB: write daily readings (batched — single executemany instead
+            # of one cursor per row, which matters when DAR_ZONES * days_back
+            # can easily run into the hundreds of inserts).
+            readings_payload = [
+                {
+                    "zone_id": reading.zone_id,
+                    "date": reading.date,
+                    "temp_mean_c": reading.temp_mean_c,
+                    "temp_max_c": reading.temp_max_c,
+                    "temp_min_c": reading.temp_min_c,
+                    "humidity_pct": reading.humidity_pct,
+                    "wind_speed_ms": reading.wind_speed_ms,
+                    "solar_rad_wm2": None,
+                    "precip_mm": reading.precip_mm,
+                    "source": reading.source,
+                    "data_quality": reading.data_quality,
+                }
+                for r in results
+                for reading in r.readings
+            ]
+            if readings_payload:
+                self._db_write(insert_daily_readings_batch, self.db, readings_payload)
 
             status = "ok" if ok_count == len(DAR_ZONES) else "partial" if ok_count > 0 else "failed"
             return StepResult(