feat: add cron scheduler initialization with validation and mutex integration

Implement initializeScheduler() and stopScheduler() functions for the
scraper cron job module. Key features:

- Config-driven enable/disable via SCRAPER_ENABLED environment variable
- Cron expression validation with fallback to default schedule (0 6 * * *)
- Minimum interval enforcement (1-hour floor) to prevent excessive runs
- Timezone support via SCRAPER_TIMEZONE configuration
- Mutex lock integration to prevent concurrent scraper executions
- Automatic lock release in finally block for error resilience
- getScheduleExpression() and getNextScheduledRun() status helpers

Add comprehensive test suite with 42 tests covering mutex locking,
scheduler lifecycle, cron validation, minimum interval enforcement,
concurrent execution prevention, and error handling.

__tests__/scraper/scraperJob.test.js

@@ -1,13 +1,46 @@
 /**
- * Tests for scraperJob.js - In-process mutex (isScraperRunning flag)
+ * Tests for scraperJob.js - In-process mutex and scheduler
  * Following TDD - these tests are written BEFORE implementation
  */
 
+// Mock node-cron before requiring scraperJob
+jest.mock('node-cron', () => ({
+  validate: jest.fn(),
+  schedule: jest.fn()
+}));
+
+// Mock the scraper logger
+jest.mock('../../services/scraperLogger', () => ({
+  createLogger: jest.fn(() => ({
+    info: jest.fn(),
+    warn: jest.fn(),
+    error: jest.fn()
+  }))
+}));
+
+// Mock uuid
+jest.mock('uuid', () => ({
+  v4: jest.fn(() => 'mock-uuid-1234')
+}));
+
+// Mock scraperService
+jest.mock('../../services/scraperService', () => ({
+  runScrape: jest.fn(() => Promise.resolve({ status: 'success' }))
+}));
+
+const cron = require('node-cron');
+const { createLogger } = require('../../services/scraperLogger');
+const { runScrape } = require('../../services/scraperService');
+
 const {
   isScraperRunning,
   getCurrentJobId,
   acquireLock,
-  releaseLock
+  releaseLock,
+  initializeScheduler,
+  stopScheduler,
+  getScheduleExpression,
+  getNextScheduledRun
 } = require('../../jobs/scraperJob');
 
 describe('scraperJob - mutex lock', () => {
@@ -147,5 +180,684 @@ describe('scraperJob - mutex lock', () => {
     test('should export releaseLock as a function', () => {
       expect(typeof releaseLock).toBe('function');
     });
+
+    test('should export initializeScheduler as a function', () => {
+      expect(typeof initializeScheduler).toBe('function');
+    });
+
+    test('should export stopScheduler as a function', () => {
+      expect(typeof stopScheduler).toBe('function');
+    });
+
+    test('should export getScheduleExpression as a function', () => {
+      expect(typeof getScheduleExpression).toBe('function');
+    });
+
+    test('should export getNextScheduledRun as a function', () => {
+      expect(typeof getNextScheduledRun).toBe('function');
+    });
+  });
+});
+
+describe('scraperJob - scheduler', () => {
+  const mockDb = { collection: jest.fn() };
+  let mockLogger;
+
+  beforeEach(() => {
+    // Reset all mocks
+    jest.clearAllMocks();
+    releaseLock();
+    if (typeof stopScheduler === 'function') {
+      stopScheduler();
+    }
+
+    // Setup mock logger
+    mockLogger = {
+      info: jest.fn(),
+      warn: jest.fn(),
+      error: jest.fn()
+    };
+    createLogger.mockReturnValue(mockLogger);
+  });
+
+  afterEach(() => {
+    releaseLock();
+    if (typeof stopScheduler === 'function') {
+      stopScheduler();
+    }
+    // Reset config module to defaults between tests
+    jest.resetModules();
+  });
+
+  describe('initializeScheduler()', () => {
+    test('should not initialize when SCRAPER_ENABLED is false', () => {
+      // We need to re-require with modified config
+      jest.resetModules();
+
+      // Mock config with SCRAPER_ENABLED = false
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: false,
+        SCRAPER_SCHEDULE: '0 6 * * *',
+        SCRAPER_TIMEZONE: 'UTC'
+      }));
+
+      // Re-mock the dependencies
+      jest.doMock('node-cron', () => ({
+        validate: jest.fn(),
+        schedule: jest.fn()
+      }));
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => ({
+          info: jest.fn(),
+          warn: jest.fn(),
+          error: jest.fn()
+        }))
+      }));
+      jest.doMock('../../services/scraperService', () => ({
+        runScrape: jest.fn()
+      }));
+      jest.doMock('uuid', () => ({
+        v4: jest.fn(() => 'mock-uuid')
+      }));
+
+      const freshCron = require('node-cron');
+      const { createLogger: freshCreateLogger } = require('../../services/scraperLogger');
+      const freshLogger = { info: jest.fn(), warn: jest.fn(), error: jest.fn() };
+      freshCreateLogger.mockReturnValue(freshLogger);
+
+      const { initializeScheduler: freshInit } = require('../../jobs/scraperJob');
+
+      freshInit(mockDb);
+
+      expect(freshCron.schedule).not.toHaveBeenCalled();
+      expect(freshLogger.info).toHaveBeenCalledWith('Scraper scheduling is disabled');
+    });
+
+    test('should validate cron expression with cron.validate()', () => {
+      jest.resetModules();
+
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: '0 6 * * *',
+        SCRAPER_TIMEZONE: 'UTC'
+      }));
+      jest.doMock('node-cron', () => ({
+        validate: jest.fn(() => true),
+        schedule: jest.fn(() => ({ stop: jest.fn() }))
+      }));
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => ({
+          info: jest.fn(), warn: jest.fn(), error: jest.fn()
+        }))
+      }));
+      jest.doMock('../../services/scraperService', () => ({
+        runScrape: jest.fn()
+      }));
+      jest.doMock('uuid', () => ({
+        v4: jest.fn(() => 'mock-uuid')
+      }));
+
+      const freshCron = require('node-cron');
+      const { initializeScheduler: freshInit } = require('../../jobs/scraperJob');
+
+      freshInit(mockDb);
+
+      expect(freshCron.validate).toHaveBeenCalledWith('0 6 * * *');
+    });
+
+    test('should fall back to default schedule 0 6 * * * if cron expression is invalid', () => {
+      jest.resetModules();
+
+      const mockConfig = {
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: 'invalid-cron',
+        SCRAPER_TIMEZONE: 'UTC'
+      };
+      jest.doMock('../../config/scraper', () => mockConfig);
+      jest.doMock('node-cron', () => ({
+        validate: jest.fn(() => false),
+        schedule: jest.fn(() => ({ stop: jest.fn() }))
+      }));
+      const freshLogger = { info: jest.fn(), warn: jest.fn(), error: jest.fn() };
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => freshLogger)
+      }));
+      jest.doMock('../../services/scraperService', () => ({
+        runScrape: jest.fn()
+      }));
+      jest.doMock('uuid', () => ({
+        v4: jest.fn(() => 'mock-uuid')
+      }));
+
+      const freshCron = require('node-cron');
+      const { initializeScheduler: freshInit } = require('../../jobs/scraperJob');
+
+      freshInit(mockDb);
+
+      // After fallback, schedule should be called with default
+      expect(freshCron.schedule).toHaveBeenCalledWith(
+        '0 6 * * *',
+        expect.any(Function),
+        expect.objectContaining({ timezone: 'UTC' })
+      );
+      expect(freshLogger.error).toHaveBeenCalledWith(
+        'Invalid cron schedule expression',
+        expect.objectContaining({ schedule: 'invalid-cron' })
+      );
+      expect(freshLogger.warn).toHaveBeenCalledWith(
+        expect.stringContaining('Falling back to default schedule')
+      );
+    });
+
+    test('should enforce minimum 1-hour interval - adjust too-frequent schedules', () => {
+      jest.resetModules();
+
+      const mockConfig = {
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: '*/5 * * * *',  // Every 5 minutes - too frequent
+        SCRAPER_TIMEZONE: 'UTC'
+      };
+      jest.doMock('../../config/scraper', () => mockConfig);
+      jest.doMock('node-cron', () => ({
+        validate: jest.fn(() => true),
+        schedule: jest.fn(() => ({ stop: jest.fn() }))
+      }));
+      const freshLogger = { info: jest.fn(), warn: jest.fn(), error: jest.fn() };
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => freshLogger)
+      }));
+      jest.doMock('../../services/scraperService', () => ({
+        runScrape: jest.fn()
+      }));
+      jest.doMock('uuid', () => ({
+        v4: jest.fn(() => 'mock-uuid')
+      }));
+
+      const freshCron = require('node-cron');
+      const { initializeScheduler: freshInit } = require('../../jobs/scraperJob');
+
+      freshInit(mockDb);
+
+      // Should adjust to hourly
+      expect(freshCron.schedule).toHaveBeenCalledWith(
+        '0 * * * *',
+        expect.any(Function),
+        expect.objectContaining({ timezone: 'UTC' })
+      );
+      expect(freshLogger.warn).toHaveBeenCalledWith(
+        expect.stringContaining('less than 1 hour'),
+        expect.objectContaining({ originalSchedule: '*/5 * * * *' })
+      );
+    });
+
+    test('should enforce minimum 1-hour interval for every-minute schedule', () => {
+      jest.resetModules();
+
+      const mockConfig = {
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: '* * * * *',  // Every minute
+        SCRAPER_TIMEZONE: 'UTC'
+      };
+      jest.doMock('../../config/scraper', () => mockConfig);
+      jest.doMock('node-cron', () => ({
+        validate: jest.fn(() => true),
+        schedule: jest.fn(() => ({ stop: jest.fn() }))
+      }));
+      const freshLogger = { info: jest.fn(), warn: jest.fn(), error: jest.fn() };
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => freshLogger)
+      }));
+      jest.doMock('../../services/scraperService', () => ({
+        runScrape: jest.fn()
+      }));
+      jest.doMock('uuid', () => ({
+        v4: jest.fn(() => 'mock-uuid')
+      }));
+
+      const freshCron = require('node-cron');
+      const { initializeScheduler: freshInit } = require('../../jobs/scraperJob');
+
+      freshInit(mockDb);
+
+      expect(freshCron.schedule).toHaveBeenCalledWith(
+        '0 * * * *',
+        expect.any(Function),
+        expect.objectContaining({ timezone: 'UTC' })
+      );
+    });
+
+    test('should create cron job with configured timezone', () => {
+      jest.resetModules();
+
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: '0 6 * * *',
+        SCRAPER_TIMEZONE: 'America/Denver'
+      }));
+      jest.doMock('node-cron', () => ({
+        validate: jest.fn(() => true),
+        schedule: jest.fn(() => ({ stop: jest.fn() }))
+      }));
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => ({
+          info: jest.fn(), warn: jest.fn(), error: jest.fn()
+        }))
+      }));
+      jest.doMock('../../services/scraperService', () => ({
+        runScrape: jest.fn()
+      }));
+      jest.doMock('uuid', () => ({
+        v4: jest.fn(() => 'mock-uuid')
+      }));
+
+      const freshCron = require('node-cron');
+      const { initializeScheduler: freshInit } = require('../../jobs/scraperJob');
+
+      freshInit(mockDb);
+
+      expect(freshCron.schedule).toHaveBeenCalledWith(
+        '0 6 * * *',
+        expect.any(Function),
+        expect.objectContaining({ timezone: 'America/Denver' })
+      );
+    });
+
+    test('should log initialization with schedule and next run time', () => {
+      jest.resetModules();
+
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: '0 6 * * *',
+        SCRAPER_TIMEZONE: 'UTC'
+      }));
+      jest.doMock('node-cron', () => ({
+        validate: jest.fn(() => true),
+        schedule: jest.fn(() => ({ stop: jest.fn() }))
+      }));
+      const freshLogger = { info: jest.fn(), warn: jest.fn(), error: jest.fn() };
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => freshLogger)
+      }));
+      jest.doMock('../../services/scraperService', () => ({
+        runScrape: jest.fn()
+      }));
+      jest.doMock('uuid', () => ({
+        v4: jest.fn(() => 'mock-uuid')
+      }));
+
+      const { initializeScheduler: freshInit } = require('../../jobs/scraperJob');
+
+      freshInit(mockDb);
+
+      expect(freshLogger.info).toHaveBeenCalledWith(
+        'Scraper scheduler initialized',
+        expect.objectContaining({
+          schedule: '0 6 * * *',
+          timezone: 'UTC'
+        })
+      );
+    });
+
+    test('should allow valid hourly schedule without adjustment', () => {
+      jest.resetModules();
+
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: '0 */2 * * *',  // Every 2 hours - acceptable
+        SCRAPER_TIMEZONE: 'UTC'
+      }));
+      jest.doMock('node-cron', () => ({
+        validate: jest.fn(() => true),
+        schedule: jest.fn(() => ({ stop: jest.fn() }))
+      }));
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => ({
+          info: jest.fn(), warn: jest.fn(), error: jest.fn()
+        }))
+      }));
+      jest.doMock('../../services/scraperService', () => ({
+        runScrape: jest.fn()
+      }));
+      jest.doMock('uuid', () => ({
+        v4: jest.fn(() => 'mock-uuid')
+      }));
+
+      const freshCron = require('node-cron');
+      const { initializeScheduler: freshInit } = require('../../jobs/scraperJob');
+
+      freshInit(mockDb);
+
+      // Should keep the original schedule, not adjust
+      expect(freshCron.schedule).toHaveBeenCalledWith(
+        '0 */2 * * *',
+        expect.any(Function),
+        expect.any(Object)
+      );
+    });
+  });
+
+  describe('cron job callback', () => {
+    test('should acquire mutex lock before running scraper', async () => {
+      jest.resetModules();
+
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: '0 6 * * *',
+        SCRAPER_TIMEZONE: 'UTC'
+      }));
+
+      let capturedCallback;
+      jest.doMock('node-cron', () => ({
+        validate: jest.fn(() => true),
+        schedule: jest.fn((expr, cb) => {
+          capturedCallback = cb;
+          return { stop: jest.fn() };
+        })
+      }));
+
+      const freshRunScrape = jest.fn(() => Promise.resolve({ status: 'success' }));
+      jest.doMock('../../services/scraperService', () => ({
+        runScrape: freshRunScrape
+      }));
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => ({
+          info: jest.fn(), warn: jest.fn(), error: jest.fn()
+        }))
+      }));
+      jest.doMock('uuid', () => ({
+        v4: jest.fn(() => 'scheduled-job-id')
+      }));
+
+      const { initializeScheduler: freshInit, isScraperRunning: freshIsRunning } = require('../../jobs/scraperJob');
+
+      freshInit(mockDb);
+
+      // Execute the cron callback
+      await capturedCallback();
+
+      // runScrape should have been called
+      expect(freshRunScrape).toHaveBeenCalledWith(
+        mockDb,
+        expect.objectContaining({ trigger: 'scheduled', jobId: 'scheduled-job-id' })
+      );
+    });
+
+    test('should release mutex lock after completion in finally block', async () => {
+      jest.resetModules();
+
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: '0 6 * * *',
+        SCRAPER_TIMEZONE: 'UTC'
+      }));
+
+      let capturedCallback;
+      jest.doMock('node-cron', () => ({
+        validate: jest.fn(() => true),
+        schedule: jest.fn((expr, cb) => {
+          capturedCallback = cb;
+          return { stop: jest.fn() };
+        })
+      }));
+
+      const freshRunScrape = jest.fn(() => Promise.resolve({ status: 'success' }));
+      jest.doMock('../../services/scraperService', () => ({
+        runScrape: freshRunScrape
+      }));
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => ({
+          info: jest.fn(), warn: jest.fn(), error: jest.fn()
+        }))
+      }));
+      jest.doMock('uuid', () => ({
+        v4: jest.fn(() => 'job-release-test')
+      }));
+
+      const { initializeScheduler: freshInit, isScraperRunning: freshIsRunning } = require('../../jobs/scraperJob');
+
+      freshInit(mockDb);
+      await capturedCallback();
+
+      // Lock should be released after completion
+      expect(freshIsRunning()).toBe(false);
+    });
+
+    test('should release mutex lock even when scraper throws an error', async () => {
+      jest.resetModules();
+
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: '0 6 * * *',
+        SCRAPER_TIMEZONE: 'UTC'
+      }));
+
+      let capturedCallback;
+      jest.doMock('node-cron', () => ({
+        validate: jest.fn(() => true),
+        schedule: jest.fn((expr, cb) => {
+          capturedCallback = cb;
+          return { stop: jest.fn() };
+        })
+      }));
+
+      const freshRunScrape = jest.fn(() => Promise.reject(new Error('Scrape failed')));
+      jest.doMock('../../services/scraperService', () => ({
+        runScrape: freshRunScrape
+      }));
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => ({
+          info: jest.fn(), warn: jest.fn(), error: jest.fn()
+        }))
+      }));
+      jest.doMock('uuid', () => ({
+        v4: jest.fn(() => 'job-error-test')
+      }));
+
+      const { initializeScheduler: freshInit, isScraperRunning: freshIsRunning } = require('../../jobs/scraperJob');
+
+      freshInit(mockDb);
+      await capturedCallback();
+
+      // Lock should be released even after error
+      expect(freshIsRunning()).toBe(false);
+    });
+
+    test('should skip run if scraper is already in progress', async () => {
+      jest.resetModules();
+
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: '0 6 * * *',
+        SCRAPER_TIMEZONE: 'UTC'
+      }));
+
+      let capturedCallback;
+      jest.doMock('node-cron', () => ({
+        validate: jest.fn(() => true),
+        schedule: jest.fn((expr, cb) => {
+          capturedCallback = cb;
+          return { stop: jest.fn() };
+        })
+      }));
+
+      const freshRunScrape = jest.fn(() => Promise.resolve({ status: 'success' }));
+      jest.doMock('../../services/scraperService', () => ({
+        runScrape: freshRunScrape
+      }));
+      const freshLogger = { info: jest.fn(), warn: jest.fn(), error: jest.fn() };
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => freshLogger)
+      }));
+      jest.doMock('uuid', () => ({
+        v4: jest.fn(() => 'job-skip-test')
+      }));
+
+      const { initializeScheduler: freshInit, acquireLock: freshAcquire } = require('../../jobs/scraperJob');
+
+      freshInit(mockDb);
+
+      // Simulate an already-running scraper
+      freshAcquire('existing-job');
+
+      await capturedCallback();
+
+      // runScrape should NOT have been called since lock was already held
+      expect(freshRunScrape).not.toHaveBeenCalled();
+      expect(freshLogger.warn).toHaveBeenCalledWith(
+        expect.stringContaining('already in progress')
+      );
+    });
+  });
+
+  describe('stopScheduler()', () => {
+    test('should stop the scheduled cron job', () => {
+      jest.resetModules();
+
+      const mockStop = jest.fn();
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: '0 6 * * *',
+        SCRAPER_TIMEZONE: 'UTC'
+      }));
+      jest.doMock('node-cron', () => ({
+        validate: jest.fn(() => true),
+        schedule: jest.fn(() => ({ stop: mockStop }))
+      }));
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => ({
+          info: jest.fn(), warn: jest.fn(), error: jest.fn()
+        }))
+      }));
+      jest.doMock('../../services/scraperService', () => ({
+        runScrape: jest.fn()
+      }));
+      jest.doMock('uuid', () => ({
+        v4: jest.fn(() => 'mock-uuid')
+      }));
+
+      const { initializeScheduler: freshInit, stopScheduler: freshStop } = require('../../jobs/scraperJob');
+
+      freshInit(mockDb);
+      freshStop();
+
+      expect(mockStop).toHaveBeenCalled();
+    });
+
+    test('should be safe to call when no scheduler is active', () => {
+      expect(() => stopScheduler()).not.toThrow();
+    });
+  });
+
+  describe('getScheduleExpression()', () => {
+    test('should return "disabled" when SCRAPER_ENABLED is false', () => {
+      jest.resetModules();
+
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: false,
+        SCRAPER_SCHEDULE: '0 6 * * *',
+        SCRAPER_TIMEZONE: 'UTC'
+      }));
+      jest.doMock('node-cron', () => ({ validate: jest.fn(), schedule: jest.fn() }));
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => ({ info: jest.fn(), warn: jest.fn(), error: jest.fn() }))
+      }));
+      jest.doMock('../../services/scraperService', () => ({ runScrape: jest.fn() }));
+      jest.doMock('uuid', () => ({ v4: jest.fn(() => 'mock-uuid') }));
+
+      const { getScheduleExpression: freshGetExpr } = require('../../jobs/scraperJob');
+
+      expect(freshGetExpr()).toBe('disabled');
+    });
+
+    test('should return the configured cron expression when enabled', () => {
+      jest.resetModules();
+
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: '30 8 * * *',
+        SCRAPER_TIMEZONE: 'UTC'
+      }));
+      jest.doMock('node-cron', () => ({ validate: jest.fn(), schedule: jest.fn() }));
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => ({ info: jest.fn(), warn: jest.fn(), error: jest.fn() }))
+      }));
+      jest.doMock('../../services/scraperService', () => ({ runScrape: jest.fn() }));
+      jest.doMock('uuid', () => ({ v4: jest.fn(() => 'mock-uuid') }));
+
+      const { getScheduleExpression: freshGetExpr } = require('../../jobs/scraperJob');
+
+      expect(freshGetExpr()).toBe('30 8 * * *');
+    });
+  });
+
+  describe('getNextScheduledRun()', () => {
+    test('should return null when SCRAPER_ENABLED is false', () => {
+      jest.resetModules();
+
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: false,
+        SCRAPER_SCHEDULE: '0 6 * * *',
+        SCRAPER_TIMEZONE: 'UTC'
+      }));
+      jest.doMock('node-cron', () => ({ validate: jest.fn(), schedule: jest.fn() }));
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => ({ info: jest.fn(), warn: jest.fn(), error: jest.fn() }))
+      }));
+      jest.doMock('../../services/scraperService', () => ({ runScrape: jest.fn() }));
+      jest.doMock('uuid', () => ({ v4: jest.fn(() => 'mock-uuid') }));
+
+      const { getNextScheduledRun: freshGetNext } = require('../../jobs/scraperJob');
+
+      expect(freshGetNext()).toBeNull();
+    });
+
+    test('should return null when no scheduler is active', () => {
+      jest.resetModules();
+
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: '0 6 * * *',
+        SCRAPER_TIMEZONE: 'UTC'
+      }));
+      jest.doMock('node-cron', () => ({ validate: jest.fn(), schedule: jest.fn() }));
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => ({ info: jest.fn(), warn: jest.fn(), error: jest.fn() }))
+      }));
+      jest.doMock('../../services/scraperService', () => ({ runScrape: jest.fn() }));
+      jest.doMock('uuid', () => ({ v4: jest.fn(() => 'mock-uuid') }));
+
+      const { getNextScheduledRun: freshGetNext } = require('../../jobs/scraperJob');
+
+      // No initializeScheduler called, so no scheduledJob
+      expect(freshGetNext()).toBeNull();
+    });
+
+    test('should return an ISO date string when scheduler is active', () => {
+      jest.resetModules();
+
+      jest.doMock('../../config/scraper', () => ({
+        SCRAPER_ENABLED: true,
+        SCRAPER_SCHEDULE: '0 6 * * *',
+        SCRAPER_TIMEZONE: 'UTC'
+      }));
+      jest.doMock('node-cron', () => ({
+        validate: jest.fn(() => true),
+        schedule: jest.fn(() => ({ stop: jest.fn() }))
+      }));
+      jest.doMock('../../services/scraperLogger', () => ({
+        createLogger: jest.fn(() => ({ info: jest.fn(), warn: jest.fn(), error: jest.fn() }))
+      }));
+      jest.doMock('../../services/scraperService', () => ({ runScrape: jest.fn() }));
+      jest.doMock('uuid', () => ({ v4: jest.fn(() => 'mock-uuid') }));
+
+      const { initializeScheduler: freshInit, getNextScheduledRun: freshGetNext } = require('../../jobs/scraperJob');
+
+      freshInit(mockDb);
+
+      const nextRun = freshGetNext();
+      // Should be a valid ISO date string
+      expect(nextRun).not.toBeNull();
+      expect(new Date(nextRun).toISOString()).toBe(nextRun);
+    });
   });
 });

jobs/scraperJob.js

@@ -1,7 +1,16 @@
+const cron = require('node-cron');
+const config = require('../config/scraper');
+const { runScrape } = require('../services/scraperService');
+const { createLogger } = require('../services/scraperLogger');
+const { v4: uuidv4 } = require('uuid');
+
 // In-process mutex state
 let isRunning = false;
 let currentJobId = null;
 
+// Scheduler state
+let scheduledJob = null;
+
 /**
  * Check if scraper is currently running
  * @returns {boolean}
@@ -40,9 +49,143 @@ function releaseLock() {
   currentJobId = null;
 }
 
+/**
+ * Get the configured schedule expression
+ * @returns {string} Cron expression or 'disabled'
+ */
+function getScheduleExpression() {
+  if (!config.SCRAPER_ENABLED) {
+    return 'disabled';
+  }
+  return config.SCRAPER_SCHEDULE;
+}
+
+/**
+ * Calculate next scheduled run time
+ * @returns {string|null} ISO timestamp or null if disabled
+ */
+function getNextScheduledRun() {
+  if (!config.SCRAPER_ENABLED || !scheduledJob) {
+    return null;
+  }
+
+  const { CronExpressionParser } = require('cron-parser');
+  try {
+    const interval = CronExpressionParser.parse(config.SCRAPER_SCHEDULE, {
+      tz: config.SCRAPER_TIMEZONE
+    });
+    return interval.next().toISOString();
+  } catch (error) {
+    return null;
+  }
+}
+
+/**
+ * Check if schedule runs more frequently than 1 hour
+ * @param {string} schedule - Cron expression
+ * @returns {boolean} True if schedule is too frequent
+ */
+function isScheduleTooFrequent(schedule) {
+  const parts = schedule.trim().split(/\s+/);
+
+  if (parts.length < 5) return false;
+
+  const minuteField = parts[0];
+
+  // If minute field is */N with N < 60, it runs more than once per hour
+  if (/^\*\/\d+$/.test(minuteField)) {
+    const interval = parseInt(minuteField.substring(2), 10);
+    if (interval < 60) return true;
+  }
+
+  // If minute field is *, it runs every minute
+  if (minuteField === '*') return true;
+
+  return false;
+}
+
+/**
+ * Initialize the scraper scheduler
+ * @param {Db} db - MongoDB database instance
+ */
+function initializeScheduler(db) {
+  const logger = createLogger('scheduler');
+
+  // Check if scheduling is enabled
+  if (!config.SCRAPER_ENABLED) {
+    logger.info('Scraper scheduling is disabled');
+    return;
+  }
+
+  // Validate cron expression
+  if (!cron.validate(config.SCRAPER_SCHEDULE)) {
+    logger.error('Invalid cron schedule expression', {
+      schedule: config.SCRAPER_SCHEDULE
+    });
+    logger.warn('Falling back to default schedule: 0 6 * * *');
+    config.SCRAPER_SCHEDULE = '0 6 * * *';
+  }
+
+  // Validate minimum interval (1 hour)
+  if (isScheduleTooFrequent(config.SCRAPER_SCHEDULE)) {
+    logger.warn('Schedule interval less than 1 hour - adjusting to hourly', {
+      originalSchedule: config.SCRAPER_SCHEDULE
+    });
+    config.SCRAPER_SCHEDULE = '0 * * * *';
+  }
+
+  // Create the scheduled job
+  scheduledJob = cron.schedule(config.SCRAPER_SCHEDULE, async () => {
+    const jobId = uuidv4();
+    const jobLogger = createLogger(jobId);
+
+    jobLogger.info('Scheduled scrape triggered');
+
+    // Check if already running
+    if (!acquireLock(jobId)) {
+      jobLogger.warn('Skipped - scrape already in progress');
+      return;
+    }
+
+    try {
+      await runScrape(db, { trigger: 'scheduled', jobId });
+    } catch (error) {
+      jobLogger.error('Scheduled scrape failed', {
+        errorType: error.name,
+        errorMessage: error.message
+      });
+    } finally {
+      releaseLock();
+    }
+  }, {
+    timezone: config.SCRAPER_TIMEZONE,
+    scheduled: true
+  });
+
+  logger.info('Scraper scheduler initialized', {
+    schedule: config.SCRAPER_SCHEDULE,
+    timezone: config.SCRAPER_TIMEZONE,
+    nextRun: getNextScheduledRun()
+  });
+}
+
+/**
+ * Stop the scheduler (for graceful shutdown)
+ */
+function stopScheduler() {
+  if (scheduledJob) {
+    scheduledJob.stop();
+    scheduledJob = null;
+  }
+}
+
 module.exports = {
   isScraperRunning,
   getCurrentJobId,
   acquireLock,
-  releaseLock
+  releaseLock,
+  getScheduleExpression,
+  getNextScheduledRun,
+  initializeScheduler,
+  stopScheduler
 };