Merge pull request #315 from blockfrost/fix/health-timeout-log

fix: timeout log even when dbsync conn succeeded

Author: slowbackspace

CHANGELOG.md

@@ -7,6 +7,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [6.3.3] - 2026-03-13
+
+### Fixed
+
+- Fixed `/health` timeout race condition where the timeout log would fire even when the DB connection succeeded in time
+
 ## [6.3.2] - 2026-03-11
 
 ### Changed

package.json

@@ -1,6 +1,6 @@
 {
   "name": "blockfrost-backend-ryo",
-  "version": "6.3.2",
+  "version": "6.3.3",
   "description": "",
   "keywords": [],
   "license": "Apache-2.0",

src/routes/health/index.ts

@@ -18,25 +18,30 @@ async function route(fastify: FastifyInstance) {
       let dbHealthy = true;
 
       if (healthCheckDbTimeoutMs !== undefined) {
-        const connected = await Promise.race([
-          getDbSync(fastify)
-            .then(client => {
-              client.release();
-              return true;
-            })
-            .catch((error: unknown) => {
-              console.error(`[HEALTH]: unhealthy — DB connection error`, error);
-              return false;
-            }),
-          new Promise<boolean>(resolve =>
-            setTimeout(() => {
-              console.error(
-                `[HEALTH]: unhealthy — DB connection timed out after ${healthCheckDbTimeoutMs}ms`,
-              );
-              resolve(false);
-            }, healthCheckDbTimeoutMs),
-          ),
-        ]);
+        let timer: ReturnType<typeof setTimeout> | undefined;
+
+        const dbPromise = getDbSync(fastify)
+          .then(client => {
+            clearTimeout(timer);
+            client.release();
+            return true;
+          })
+          .catch((error: unknown) => {
+            clearTimeout(timer);
+            console.error(`[HEALTH]: unhealthy — DBSync connection error`, error);
+            return false;
+          });
+
+        const timeoutPromise = new Promise<boolean>(resolve => {
+          timer = setTimeout(() => {
+            console.error(
+              `[HEALTH]: unhealthy — DBSync did not respond within ${healthCheckDbTimeoutMs}ms`,
+            );
+            resolve(false);
+          }, healthCheckDbTimeoutMs);
+        });
+
+        const connected = await Promise.race([dbPromise, timeoutPromise]);
 
         if (!connected) {
           dbHealthy = false;

test/unit/tests/routes/health.unit.ts

@@ -66,4 +66,29 @@ describe('health endpoints tests', () => {
 
     fastify.close();
   });
+
+  test('does not log timeout error when DB responds before healthCheckDbTimeoutMs', async () => {
+    // Use a short timeout so we can wait past it and verify the log never fires
+    mainConfig.server.healthCheckDbTimeoutMs = 50;
+
+    const fastify = buildFastify();
+    const errorSpy = vi.spyOn(console, 'error');
+
+    vi.spyOn(databaseUtils, 'getDbSync').mockReturnValue(
+      // @ts-expect-error test
+      Promise.resolve({ release: () => null }),
+    );
+
+    await fastify.ready();
+    const response = await supertest(fastify.server).get('/health');
+
+    expect(response.body).toEqual({ is_healthy: true });
+
+    // Wait past the timeout to ensure the timer was actually cancelled
+    await new Promise(resolve => setTimeout(resolve, 100));
+
+    expect(errorSpy).not.toHaveBeenCalledWith(expect.stringContaining('did not respond within'));
+
+    fastify.close();
+  });
 });