fix(webapp,database): address Devin review on the driver-adapter path

- Pass the datasource schema (?schema=) to PrismaPg as its {schema} option so
  custom-schema installs keep talking to the right schema on the adapter (the
  adapter does not honor ?schema= in the connection string).
- Set disposeExternalPool: true so $disconnect() closes the pg pool instead of
  leaking sockets, matching the engine-driver path.
- Guard the two $metrics consumers (the /metrics route and the OTel batch
  observable callback) so a client on a driver adapter degrades to empty metrics
  instead of failing the scrape / rejecting the callback.
- isPrismaRetriableError checks the adapter acquire-timeout message independently
  of the coded-error branch, so the pool-acquire retry still engages if the
  timeout arrives wrapped as a coded error.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: ericallam

apps/webapp/app/db.server.ts

@@ -456,7 +456,15 @@ function buildDriverAdapterPool(
       ignoreError: true,
     });
   });
-  return new PrismaPg(pool);
+
+  let schema: string | undefined;
+  try {
+    schema = new URL(connectionString).searchParams.get("schema") ?? undefined;
+  } catch {
+    schema = undefined;
+  }
+
+  return new PrismaPg(pool, { schema, disposeExternalPool: true });
 }
 
 // Generalized writer builder shared by the control-plane client and the run-ops

apps/webapp/app/routes/metrics.ts

@@ -14,7 +14,12 @@ export async function loader({ request }: LoaderFunctionArgs) {
   }
 
   // We need to remove empty lines from the prisma metrics, grafana doesn't like them
-  const prismaMetrics = (await prisma.$metrics.prometheus()).replace(/^\s*[\r\n]/gm, "");
+  let prismaMetrics = "";
+  try {
+    prismaMetrics = (await prisma.$metrics.prometheus()).replace(/^\s*[\r\n]/gm, "");
+  } catch {
+    prismaMetrics = "";
+  }
   const coreMetrics = await metricsRegister.metrics();
 
   // Order matters, core metrics end with `# EOF`, prisma metrics don't

apps/webapp/app/v3/tracer.server.ts

@@ -551,7 +551,13 @@ function configurePrismaMetrics({ meter }: { meter: Meter }) {
 
   meter.addBatchObservableCallback(
     async (res) => {
-      const { counters, gauges, histograms } = await readPrismaMetrics();
+      let prismaMetrics: Awaited<ReturnType<typeof readPrismaMetrics>>;
+      try {
+        prismaMetrics = await readPrismaMetrics();
+      } catch {
+        return;
+      }
+      const { counters, gauges, histograms } = prismaMetrics;
 
       // Observe counters
       res.observe(queriesTotal, counters.queriesTotal);

internal-packages/database/src/transaction.ts

@@ -40,8 +40,8 @@ const retryCodes = ["P2024", "P2028", "P2034"];
 const ADAPTER_ACQUIRE_TIMEOUT = /timeout exceeded when trying to connect/i;
 
 export function isPrismaRetriableError(error: unknown): boolean {
-  if (isPrismaKnownError(error)) {
-    return retryCodes.includes(error.code);
+  if (isPrismaKnownError(error) && retryCodes.includes(error.code)) {
+    return true;
   }
 
   const message = (error as { message?: unknown })?.message;