fix: catch unhandled promise rejections in logging middleware (#291)

* fix: catch unhandled promise rejections in logging middleware

* test(api_usage): assert exact Redis key pattern and TTL in incrWithTtlAtomic assertion

Author: Kirtan-pc

apps/public-api/src/__tests__/api_usage.test.js

@@ -0,0 +1,142 @@
+'use strict';
+
+const mockLogCreate = jest.fn();
+const mockApiAnalyticsCreate = jest.fn();
+const mockIncrWithTtlAtomic = jest.fn();
+
+jest.mock('@urbackend/common', () => ({
+    Log: {
+        create: (...args) => mockLogCreate(...args),
+    },
+    ApiAnalytics: {
+        create: (...args) => mockApiAnalyticsCreate(...args),
+    },
+    redis: {
+        set: jest.fn().mockResolvedValue(null),
+    },
+    getDayKey: () => '2026-06-08',
+    DEFAULT_DAILY_TTL_SECONDS: 86400,
+    incrWithTtlAtomic: (...args) => mockIncrWithTtlAtomic(...args),
+}));
+
+const { logger } = require('../middlewares/api_usage');
+
+describe('api_usage middleware', () => {
+    let req, res, next;
+    let finishCallback;
+
+    beforeEach(() => {
+        jest.clearAllMocks();
+        req = {
+            project: { _id: 'test_project_id' },
+            method: 'GET',
+            originalUrl: '/api/data/test-endpoint',
+            ip: '127.0.0.1',
+            _dailyCountIncremented: false,
+        };
+        res = {
+            statusCode: 200,
+            on: jest.fn((event, cb) => {
+                if (event === 'finish') {
+                    finishCallback = cb;
+                }
+            }),
+        };
+        next = jest.fn();
+    });
+
+    test('registers finish listener and calls next()', () => {
+        logger(req, res, next);
+        expect(next).toHaveBeenCalled();
+        expect(res.on).toHaveBeenCalledWith('finish', expect.any(Function));
+    });
+
+    test('does not register finish listener for non-analytics routes', () => {
+        req.originalUrl = '/other/route';
+        logger(req, res, next);
+        expect(next).toHaveBeenCalled();
+        expect(res.on).not.toHaveBeenCalled();
+    });
+
+    test('handles successful Log.create and ApiAnalytics.create', async () => {
+        mockLogCreate.mockResolvedValue({ _id: 'log_id' });
+        mockApiAnalyticsCreate.mockResolvedValue({ _id: 'analytics_id' });
+        mockIncrWithTtlAtomic.mockResolvedValue(1);
+
+        const consoleLogSpy = jest.spyOn(console, 'log').mockImplementation(() => {});
+
+        logger(req, res, next);
+        expect(finishCallback).toBeDefined();
+
+        // Trigger finish callback
+        await finishCallback();
+
+        expect(mockLogCreate).toHaveBeenCalledWith({
+            projectId: 'test_project_id',
+            method: 'GET',
+            path: '/api/data/test-endpoint',
+            status: 200,
+            ip: '127.0.0.1',
+        });
+        // Assert the exact Redis key pattern and TTL value, not just invocation
+        expect(mockIncrWithTtlAtomic).toHaveBeenCalledWith(
+            expect.anything(), // redis instance
+            'project:usage:req:count:test_project_id:2026-06-08',
+            86400
+        );
+
+        // Wait for setImmediate callbacks to execute
+        await new Promise((resolve) => setImmediate(resolve));
+
+        expect(mockApiAnalyticsCreate).toHaveBeenCalledWith({
+            projectId: 'test_project_id',
+            endpoint: '/api/data/test-endpoint',
+            method: 'GET',
+            statusCode: 200,
+            responseTimeMs: expect.any(Number),
+        });
+
+        expect(consoleLogSpy).toHaveBeenCalledWith(expect.stringContaining('Logged: GET /api/data/test-endpoint'));
+        consoleLogSpy.mockRestore();
+    });
+
+    test('handles Log.create database failure gracefully without crashing', async () => {
+        const dbError = new Error('Database connection failed');
+        mockLogCreate.mockRejectedValue(dbError);
+        mockApiAnalyticsCreate.mockResolvedValue({ _id: 'analytics_id' });
+        mockIncrWithTtlAtomic.mockResolvedValue(1);
+
+        const consoleErrorSpy = jest.spyOn(console, 'error').mockImplementation(() => {});
+
+        logger(req, res, next);
+        await finishCallback();
+
+        // Log.create is fire-and-forget, so it will resolve/reject asynchronously.
+        // We wait a tiny bit to make sure its catch block runs.
+        await new Promise((resolve) => setTimeout(resolve, 10));
+
+        expect(mockLogCreate).toHaveBeenCalled();
+        expect(consoleErrorSpy).toHaveBeenCalledWith('Logging failed:', dbError.message);
+
+        consoleErrorSpy.mockRestore();
+    });
+
+    test('handles ApiAnalytics.create database failure gracefully without crashing', async () => {
+        mockLogCreate.mockResolvedValue({ _id: 'log_id' });
+        const analyticsError = new Error('Analytics write failed');
+        mockApiAnalyticsCreate.mockRejectedValue(analyticsError);
+
+        const consoleErrorSpy = jest.spyOn(console, 'error').mockImplementation(() => {});
+
+        logger(req, res, next);
+        await finishCallback();
+
+        // Wait for setImmediate to trigger the analytics write and catch block
+        await new Promise((resolve) => setImmediate(resolve));
+
+        expect(mockApiAnalyticsCreate).toHaveBeenCalled();
+        expect(consoleErrorSpy).toHaveBeenCalledWith('Failed to save API analytics:', analyticsError.message);
+
+        consoleErrorSpy.mockRestore();
+    });
+});

apps/public-api/src/middlewares/api_usage.js

@@ -38,6 +38,8 @@ const logger = (req, res, next) => {
                         path: req.originalUrl,
                         status: res.statusCode,
                         ip: req.ip
+                    }).catch((e) => {
+                        console.error("Logging failed:", e.message);
                     });
 
                     // Usage counter (Redis): daily API requests per project
@@ -68,7 +70,7 @@ const logger = (req, res, next) => {
                             responseTimeMs: parseFloat(responseTimeMs),
                         });
                     } catch (err) {
-                        console.error('Failed to save API analytics:', err);
+                        console.error('Failed to save API analytics:', err.message || err);
                     }
                 });
             }