feat: Implement background scheduler initialization to prevent race conditions in multi-worker deployments

.gitignore

@@ -2,4 +2,6 @@ dist
 logs
 certs
 build
-.venv
+.venv
+__pycache__
+.pyc

Web/app.py

@@ -1123,6 +1123,8 @@ def update_appointment_statuses():
 
         for appointment in appointments_to_check:
             old_status = appointment.get('Status')
+            activation_user = str(appointment.get('User') or '').strip()
+            activation_item_name = str(appointment.get('Item') or 'Termin')
 
             # Aktuellen Status bestimmen
             new_status = au.get_current_status(appointment, log_changes=True, user='scheduler')
@@ -1138,6 +1140,7 @@ def update_appointment_statuses():
                     item_id_str = appointment.get('Item')
                     conflict_detected = False
                     conflict_note = ''
+                    item_name = item_id_str or 'Termin'
                     if item_id_str:
                         try:
                             item_doc = items_col.find_one(
@@ -1145,6 +1148,8 @@ def update_appointment_statuses():
                                 {'Verfuegbar': 1, 'User': 1, 'Name': 1, 'Exemplare': 1}
                             )
                             if item_doc:
+                                item_name = item_doc.get('Name', item_id_str)
+                                activation_item_name = item_name
                                 total_exemplare = int(item_doc.get('Exemplare', 1))
                                 # Count how many active (non-planned) borrows currently hold this item
                                 active_borrows = ausleihungen.count_documents({
@@ -1194,6 +1199,31 @@ def update_appointment_statuses():
                     elif new_status == 'completed':
                         completed_count += 1
 
+                # Create activation notification even if another worker already updated the status.
+                if old_status == 'planned' and new_status == 'active' and activation_user:
+                    try:
+                        _create_notification(
+                            db,
+                            audience='user',
+                            notif_type='appointment_activated',
+                            title='Reservierung ist jetzt aktiv',
+                            message=(
+                                f"Deine geplante Ausleihe für {activation_item_name} startet jetzt."
+                            ),
+                            target_user=activation_user,
+                            reference={
+                                'appointment_id': str(appointment.get('_id')),
+                                'item_id': str(appointment.get('Item') or ''),
+                                'event': 'activated',
+                            },
+                            unique_key=f"appointment:activated:{appointment.get('_id')}",
+                            severity='info',
+                        )
+                    except Exception as notif_err:
+                        app.logger.warning(
+                            f"Failed to create activation notification for {appointment.get('_id')}: {notif_err}"
+                        )
+
         client.close()
 
         if updated_count > 0:
@@ -1204,17 +1234,62 @@ def update_appointment_statuses():
     except Exception as e:
         app.logger.error(f"Automatic appointment status update failed: {e}")
 
-# Schedule jobs
+# Schedule jobs - only start scheduler if this is the main process or a single-worker deployment
+# This prevents race conditions in multi-worker Gunicorn environments
 scheduler = BackgroundScheduler()
-if cfg.SCHEDULER_ENABLED:
-    scheduler.add_job(func=create_daily_backup, trigger="interval", hours=cfg.BACKUP_INTERVAL_HOURS)
-    scheduler.add_job(func=update_appointment_statuses, trigger="interval", minutes=cfg.SCHEDULER_INTERVAL_MIN)
-    scheduler.add_job(func=create_return_reminders, trigger="interval", minutes=cfg.SCHEDULER_INTERVAL_MIN)
-    scheduler.start()
+_scheduler_initialized = False
+
+def _initialize_scheduler():
+    """Initialize the background scheduler in a safe way for multi-worker deployments."""
+    global _scheduler_initialized
+    if _scheduler_initialized or not cfg.SCHEDULER_ENABLED:
+        return
+    
+    try:
+        # For multi-worker Gunicorn, check if we're in a reasonable scenario
+        # Using a lock file to ensure only one instance starts the scheduler
+        scheduler_lock_path = os.path.join(os.path.dirname(os.path.dirname(__file__)), '.scheduler_lock')
+        
+        try:
+            # Try to create the lock file - only succeeds if it doesn't exist
+            lock_fd = os.open(scheduler_lock_path, os.O_CREAT | os.O_EXCL | os.O_WRONLY, 0o644)
+            os.close(lock_fd)
+            should_start = True
+        except FileExistsError:
+            should_start = False
+            app.logger.warning("Scheduler lock exists - another process is already running the scheduler")
+        
+        if should_start:
+            scheduler.add_job(func=create_daily_backup, trigger="interval", hours=cfg.BACKUP_INTERVAL_HOURS)
+            scheduler.add_job(func=update_appointment_statuses, trigger="interval", minutes=cfg.SCHEDULER_INTERVAL_MIN)
+            scheduler.add_job(func=create_return_reminders, trigger="interval", minutes=cfg.SCHEDULER_INTERVAL_MIN)
+            scheduler.start()
+            _scheduler_initialized = True
+            app.logger.info(f"Scheduler started successfully (interval={cfg.SCHEDULER_INTERVAL_MIN} min)")
+        else:
+            app.logger.info("Scheduler skipped - another worker instance is running it")
+    except Exception as e:
+        app.logger.error(f"Failed to initialize scheduler: {e}")
+        _scheduler_initialized = False
+
+# Initialize scheduler on app startup
+_initialize_scheduler()
 
 # Register shutdown handler to stop scheduler when app is terminated
 import atexit
-atexit.register(lambda: scheduler.shutdown() if cfg.SCHEDULER_ENABLED else None)
+def _shutdown_scheduler():
+    if cfg.SCHEDULER_ENABLED and _scheduler_initialized:
+        try:
+            scheduler.shutdown()
+            lock_path = os.path.join(os.path.dirname(os.path.dirname(__file__)), '.scheduler_lock')
+            try:
+                os.remove(lock_path)
+            except Exception:
+                pass
+        except Exception as e:
+            app.logger.error(f"Error during scheduler shutdown: {e}")
+
+atexit.register(_shutdown_scheduler)
 
 def allowed_file(filename, file_content=None, max_size_mb=cfg.MAX_UPLOAD_MB):
     """
@@ -4040,6 +4115,9 @@ def get_items():
             'Filter3': 1,
             'Ort': 1,
             'User': 1,
+            'BlockedNow': 1,
+            'Reservierbar': 1,
+            'HasDamage': 1,
             'ItemType': 1,
         }
 

Web/templates/main.html

@@ -799,10 +799,8 @@
     }
 
     function loadItems(offset = 0, append = false) {
-        // Für Pages nach der ersten: Explizit vollständige Daten laden (light_mode=false)
-        // Erste Page: light_mode wird automatisch enablet
-        const lightModeParam = offset > 0 ? '&light_mode=false' : '';
-        return fetch(`{{ url_for('get_items') }}?offset=${offset}&limit=${MAIN_ITEMS_PAGE_SIZE}${lightModeParam}`)
+        // Keep list payload lightweight; full details are fetched on-demand in openItemQuick.
+        return fetch(`{{ url_for('get_items') }}?offset=${offset}&limit=${MAIN_ITEMS_PAGE_SIZE}&light_mode=true`)
             .then(response => response.json())
             .then(data => {
                 const itemsContainer = document.querySelector('#items-container');
@@ -1073,12 +1071,9 @@
                                 
                                 // Stop event from bubbling up
                                 e.stopPropagation();
-                                
-                                // Get full item data with correct image paths
-                                const modalItemData = {...item};
-                                modalItemData.Images = item.Images ? item.Images.map(img => "{{ url_for('uploaded_file', filename='') }}" + img) : [];
-                                
-                                openItemModal(modalItemData);
+
+                                // Always load full, up-to-date item details for the modal.
+                                openItemQuick(item._id);
                             });
                         }
                     } catch (err) {
@@ -1414,6 +1409,76 @@
     }
 
     function openItemModal(item) {
+        const escapeHtml = (value) => String(value ?? '')
+            .replace(/&/g, '&')
+            .replace(/</g, '&lt;')
+            .replace(/>/g, '&gt;')
+            .replace(/"/g, '&quot;')
+            .replace(/'/g, '&#39;');
+
+        const formatHistoryDate = (value) => {
+            if (!value) return '-';
+            const dt = new Date(value);
+            if (Number.isNaN(dt.getTime())) {
+                return escapeHtml(value);
+            }
+            return dt.toLocaleString('de-DE', { day: '2-digit', month: '2-digit', year: 'numeric', hour: '2-digit', minute: '2-digit' });
+        };
+
+        const damageReports = Array.isArray(item.DamageReports) ? item.DamageReports : [];
+        const damageRepairs = Array.isArray(item.DamageRepairs) ? item.DamageRepairs : [];
+        const damageHistoryEntries = [];
+
+        damageReports.forEach((report) => {
+            damageHistoryEntries.push({
+                type: 'report',
+                rawDate: report?.reported_at || null,
+                dateLabel: formatHistoryDate(report?.reported_at),
+                actor: escapeHtml(report?.reported_by || '-'),
+                description: escapeHtml(report?.description || 'Schaden gemeldet'),
+                meta: '',
+            });
+        });
+
+        damageRepairs.forEach((repair) => {
+            const resolvedReports = Array.isArray(repair?.resolved_reports) ? repair.resolved_reports : [];
+            damageHistoryEntries.push({
+                type: 'repair',
+                rawDate: repair?.repaired_at || null,
+                dateLabel: formatHistoryDate(repair?.repaired_at),
+                actor: escapeHtml(repair?.repaired_by || '-'),
+                description: 'Als repariert markiert',
+                meta: `${resolvedReports.length} Meldung(en) abgeschlossen`,
+            });
+        });
+
+        damageHistoryEntries.sort((a, b) => {
+            const ta = a.rawDate ? new Date(a.rawDate).getTime() : 0;
+            const tb = b.rawDate ? new Date(b.rawDate).getTime() : 0;
+            return (Number.isNaN(tb) ? 0 : tb) - (Number.isNaN(ta) ? 0 : ta);
+        });
+
+        const damageHistoryHtml = damageHistoryEntries.length
+            ? damageHistoryEntries.map((entry) => {
+                const badgeStyle = entry.type === 'repair'
+                    ? 'background:#dcfce7;color:#166534;'
+                    : 'background:#fee2e2;color:#991b1b;';
+                const badgeText = entry.type === 'repair' ? 'Repariert' : 'Schaden';
+                const metaLine = entry.meta ? `<div style="font-size:0.84rem;color:#4b5563;">${escapeHtml(entry.meta)}</div>` : '';
+                return `
+                    <div style="border:1px solid #dbe3ee;border-radius:8px;padding:10px;background:#fff;display:grid;gap:6px;">
+                        <div style="display:flex;flex-wrap:wrap;gap:8px;align-items:center;">
+                            <span style="display:inline-block;padding:2px 8px;border-radius:999px;font-size:0.75rem;font-weight:700;${badgeStyle}">${badgeText}</span>
+                            <span style="font-size:0.84rem;color:#475569;">${entry.dateLabel}</span>
+                        </div>
+                        <div style="font-size:0.9rem;color:#0f172a;"><strong>Von:</strong> ${entry.actor}</div>
+                        <div style="font-size:0.92rem;color:#1f2937;">${entry.description}</div>
+                        ${metaLine}
+                    </div>
+                `;
+            }).join('')
+            : '<div style="font-size:0.92rem;color:#64748b;">Keine Beschädigungs-Historie vorhanden.</div>';
+
         // Get modal elements
         const modal = document.getElementById('item-modal');
         const modalContent = document.getElementById('modal-content-wrapper');
@@ -1571,6 +1636,19 @@
                     <div class="detail-value">${item.Beschreibung || '-'}</div>
                 </div>
 
+                <div class="detail-group full-width" style="margin-top:12px;">
+                    <div class="detail-label" style="font-weight:600; color:#374151;">Beschädigungs-Historie</div>
+                    <div class="detail-value">
+                        <button id="toggle-damage-history" class="calendar-toggle-btn" style="margin-bottom:12px; padding:10px 16px; border-radius:6px; background:#f3f4f6; border:1px solid #d1d5db; font-weight:500; cursor:pointer; display:inline-flex; align-items:center; gap:8px; transition:all 0.2s ease;">
+                            <span>🛠️</span>
+                            <span id="toggle-damage-history-text">Historie anzeigen</span>
+                        </button>
+                        <div id="damage-history-panel" style="display:none; margin-top:8px; border:1px solid #e7edf5; border-radius:10px; padding:12px; background:#f8fafc;">
+                            <div style="display:grid; gap:10px;">${damageHistoryHtml}</div>
+                        </div>
+                    </div>
+                </div>
+
                 <div class="detail-group full-width" style="margin-top:14px; padding:12px; border:1px solid #e5e7eb; border-radius:10px; background:#fbfbfd; box-shadow: 0 1px 1px rgba(0,0,0,0.03);">
                     <div class="detail-label" style="font-weight:600; color:#374151;">Verfügbarkeit prüfen</div>
                     <div class="detail-value">
@@ -1687,6 +1765,9 @@
         const detailsPanel = document.getElementById('calendar-day-details');
         const detailsDate = document.getElementById('cal-details-date');
         const detailsList = document.getElementById('cal-details-list');
+        const damageToggleBtn = document.getElementById('toggle-damage-history');
+        const damageHistoryPanel = document.getElementById('damage-history-panel');
+        const damageToggleText = document.getElementById('toggle-damage-history-text');
 
         let bookings = [];
         let currentDate = new Date();
@@ -1847,6 +1928,16 @@
             renderCalendar();
         });
 
+        damageToggleBtn?.addEventListener('click', () => {
+            const shouldOpen = damageHistoryPanel.style.display === 'none';
+            damageHistoryPanel.style.display = shouldOpen ? 'block' : 'none';
+            if (damageToggleText) {
+                damageToggleText.textContent = shouldOpen ? 'Historie verbergen' : 'Historie anzeigen';
+            }
+            damageToggleBtn.style.background = shouldOpen ? '#e0e7ff' : '#f3f4f6';
+            damageToggleBtn.style.borderColor = shouldOpen ? '#818cf8' : '#d1d5db';
+        });
+
         // Availability checker (user)
         const availDate = document.getElementById('avail-date');
         const availStart = document.getElementById('avail-start');

Web/templates/main_admin.html

@@ -3415,10 +3415,8 @@ document.addEventListener('DOMContentLoaded', ()=>{
     }
 
     function loadItems(offset = 0, append = false) {
-        // Für Pages nach der ersten: Explizit vollständige Daten laden (light_mode=false)
-        // Erste Page: light_mode wird automatisch enablet
-        const lightModeParam = offset > 0 ? '&light_mode=false' : '';
-        return fetch(`{{ url_for('get_items') }}?offset=${offset}&limit=${MAIN_ADMIN_ITEMS_PAGE_SIZE}${lightModeParam}`)
+        // Keep list payload lightweight; full details are fetched on-demand in openItemQuick.
+        return fetch(`{{ url_for('get_items') }}?offset=${offset}&limit=${MAIN_ADMIN_ITEMS_PAGE_SIZE}&light_mode=true`)
             .then(response => response.json())
             .then(data => {
                 const itemsContainer = document.querySelector('#items-container');
@@ -3592,6 +3590,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
                             }
                         }
                         const damageCount = Array.isArray(item.DamageReports) ? item.DamageReports.length : 0;
+                        const hasDamage = Boolean(item.HasDamage) || damageCount > 0;
                         const groupedCount = Number(item.GroupedDisplayCount || 1);
                         const availableGroupedCount = Number(item.AvailableGroupedCount ?? (item.Verfuegbar ? 1 : 0));
                         const isGroupedItem = groupedCount > 1;
@@ -3608,7 +3607,7 @@ document.addEventListener('DOMContentLoaded', ()=>{
                                 <p class="item-col-filter3"><strong>Thema:</strong> ${filter3Display}${filter3More}</p>
                                 <p class="item-col-code"><strong>Barcode:</strong> ${item.Code_4 || '-'}</p>
                                 <p class="item-col-count"><strong>Anzahl:</strong> ${groupedCount}</p>
-                                ${damageCount > 0 ? `<div class="damage-badge">Schäden gemeldet: ${damageCount}</div>` : ''}
+                                ${hasDamage ? `<div class="damage-badge">${damageCount > 0 ? `Schäden gemeldet: ${damageCount}` : 'Schäden gemeldet'}</div>` : ''}
                                 <div class="image-container">
                                     ${imagesHtml}
                                 </div>
@@ -3680,11 +3679,8 @@ document.addEventListener('DOMContentLoaded', ()=>{
                                 }
                                 
                                 e.stopPropagation();
-                                
-                                const modalItemData = {...item};
-                                modalItemData.Images = item.Images ? item.Images.map(img => "{{ url_for('uploaded_file', filename='') }}" + img) : [];
-                                
-                                openItemModal(modalItemData);
+
+                                openItemQuick(item._id);
                             });
                         }
                     } catch (err) {
@@ -4004,6 +4000,22 @@ document.addEventListener('DOMContentLoaded', ()=>{
         applyFilters();
     }
 
+    // Open item modal with fresh details from backend.
+    function openItemQuick(id) {
+        fetch(`/get_item/${id}`)
+            .then(response => response.json())
+            .then(item => {
+                if (item && !item.error) {
+                    openItemModal(item);
+                } else {
+                    console.error('Item details could not be loaded:', item);
+                }
+            })
+            .catch(err => {
+                console.error('Error loading item details:', err);
+            });
+    }
+
     function openEditModalForSelectedUnit(defaultItemId, selectId) {
         let targetItemId = defaultItemId;
 
@@ -4303,14 +4315,58 @@ document.addEventListener('DOMContentLoaded', ()=>{
         }
 
         const damageReports = Array.isArray(item.DamageReports) ? item.DamageReports : [];
-        const damageInfoHtml = damageReports.length > 0
-            ? `<ul class="damage-list">${damageReports.map(report => {
-                const desc = escapeHtml(report?.description || '-');
-                const by = escapeHtml(report?.reported_by || 'Unbekannt');
-                const at = escapeHtml(formatDamageTimestamp(report?.reported_at));
-                return `<li><strong>${at}</strong> durch ${by}<br>${desc}</li>`;
-            }).join('')}</ul>`
-            : 'Keine Schäden erfasst.';
+        const damageRepairs = Array.isArray(item.DamageRepairs) ? item.DamageRepairs : [];
+        const damageHistoryEntries = [];
+
+        damageReports.forEach(report => {
+            damageHistoryEntries.push({
+                type: 'report',
+                timestamp: report?.reported_at || null,
+                dateLabel: escapeHtml(formatDamageTimestamp(report?.reported_at)),
+                actor: escapeHtml(report?.reported_by || 'Unbekannt'),
+                description: escapeHtml(report?.description || 'Schaden gemeldet'),
+                meta: '',
+            });
+        });
+
+        damageRepairs.forEach(repair => {
+            const resolvedReports = Array.isArray(repair?.resolved_reports) ? repair.resolved_reports : [];
+            damageHistoryEntries.push({
+                type: 'repair',
+                timestamp: repair?.repaired_at || null,
+                dateLabel: escapeHtml(formatDamageTimestamp(repair?.repaired_at)),
+                actor: escapeHtml(repair?.repaired_by || 'Unbekannt'),
+                description: 'Als repariert markiert',
+                meta: `${resolvedReports.length} Meldung(en) abgeschlossen`,
+            });
+        });
+
+        damageHistoryEntries.sort((a, b) => {
+            const ta = a.timestamp ? new Date(a.timestamp).getTime() : 0;
+            const tb = b.timestamp ? new Date(b.timestamp).getTime() : 0;
+            return (Number.isNaN(tb) ? 0 : tb) - (Number.isNaN(ta) ? 0 : ta);
+        });
+
+        const damageHistoryHtml = damageHistoryEntries.length > 0
+            ? damageHistoryEntries.map(entry => {
+                const badgeStyle = entry.type === 'repair'
+                    ? 'background:#dcfce7;color:#166534;'
+                    : 'background:#fee2e2;color:#991b1b;';
+                const badgeText = entry.type === 'repair' ? 'Repariert' : 'Schaden';
+                const metaLine = entry.meta ? `<div style="font-size:0.84rem;color:#4b5563;">${escapeHtml(entry.meta)}</div>` : '';
+                return `
+                    <div style="border:1px solid #dbe3ee;border-radius:8px;padding:10px;background:#fff;display:grid;gap:6px;">
+                        <div style="display:flex;flex-wrap:wrap;gap:8px;align-items:center;">
+                            <span style="display:inline-block;padding:2px 8px;border-radius:999px;font-size:0.75rem;font-weight:700;${badgeStyle}">${badgeText}</span>
+                            <span style="font-size:0.84rem;color:#475569;">${entry.dateLabel}</span>
+                        </div>
+                        <div style="font-size:0.9rem;color:#0f172a;"><strong>Von:</strong> ${entry.actor}</div>
+                        <div style="font-size:0.92rem;color:#1f2937;">${entry.description}</div>
+                        ${metaLine}
+                    </div>
+                `;
+            }).join('')
+            : '<div style="font-size:0.92rem;color:#64748b;">Keine Beschädigungs-Historie vorhanden.</div>';
         
         modalContent.innerHTML = `
             <h2>${item.Name}</h2>
@@ -4385,9 +4441,17 @@ document.addEventListener('DOMContentLoaded', ()=>{
                     <div class="detail-value">${item.Beschreibung || '-'}</div>
                 </div>
 
-                <div class="detail-group full-width">
-                    <div class="detail-label">Schäden:</div>
-                    <div class="detail-value">${damageInfoHtml}</div>
+                <div class="detail-group full-width" style="margin-top:12px;">
+                    <div class="detail-label" style="font-weight:600; color:#374151;">Beschädigungs-Historie</div>
+                    <div class="detail-value">
+                        <button id="toggle-damage-history" class="calendar-toggle-btn" style="margin-bottom:12px; padding:10px 16px; border-radius:6px; background:#f3f4f6; border:1px solid #d1d5db; font-weight:500; cursor:pointer; display:inline-flex; align-items:center; gap:8px; transition:all 0.2s ease;">
+                            <span>🛠️</span>
+                            <span id="toggle-damage-history-text">Historie anzeigen</span>
+                        </button>
+                        <div id="damage-history-panel" style="display:none; margin-top:8px; border:1px solid #e7edf5; border-radius:10px; padding:12px; background:#f8fafc;">
+                            <div style="display:grid; gap:10px;">${damageHistoryHtml}</div>
+                        </div>
+                    </div>
                 </div>
 
                 <div class="detail-group full-width" style="margin-top:12px; padding:10px; border:1px solid #e3e3e3; border-radius:8px;">
@@ -4486,6 +4550,9 @@ document.addEventListener('DOMContentLoaded', ()=>{
         const detailsPanel = document.getElementById('calendar-day-details');
         const detailsDate = document.getElementById('cal-details-date');
         const detailsList = document.getElementById('cal-details-list');
+        const damageToggleBtn = document.getElementById('toggle-damage-history');
+        const damageHistoryPanel = document.getElementById('damage-history-panel');
+        const damageToggleText = document.getElementById('toggle-damage-history-text');
 
         let bookings = [];
         let currentDate = new Date();
@@ -4645,6 +4712,16 @@ document.addEventListener('DOMContentLoaded', ()=>{
             renderCalendar();
         });
 
+        damageToggleBtn?.addEventListener('click', () => {
+            const shouldOpen = damageHistoryPanel.style.display === 'none';
+            damageHistoryPanel.style.display = shouldOpen ? 'block' : 'none';
+            if (damageToggleText) {
+                damageToggleText.textContent = shouldOpen ? 'Historie verbergen' : 'Historie anzeigen';
+            }
+            damageToggleBtn.style.background = shouldOpen ? '#e0e7ff' : '#f3f4f6';
+            damageToggleBtn.style.borderColor = shouldOpen ? '#818cf8' : '#d1d5db';
+        });
+
 
         // Availability checker
         const availDate = document.getElementById('avail-date');

gunicorn.conf.py

@@ -0,0 +1,42 @@
+"""
+Gunicorn configuration for Inventarsystem.
+
+This configuration ensures that:
+1. The BackgroundScheduler runs reliably in only one worker process
+2. Appointment status updates and reminders work correctly
+3. Multi-worker deployments don't cause race conditions
+"""
+
+import os
+import sys
+from pathlib import Path
+
+# Get project root
+PROJECT_ROOT = Path(__file__).parent
+
+# Basic configuration
+bind = "unix:/tmp/inventarsystem.sock"
+workers = 1  # CRITICAL: Only 1 worker to prevent BackgroundScheduler race conditions
+worker_class = "sync"
+timeout = 60
+graceful_timeout = 20
+max_requests = 1000
+max_requests_jitter = 100
+
+# Logging
+accesslog = str(PROJECT_ROOT / "logs" / "access.log")
+errorlog = str(PROJECT_ROOT / "logs" / "error.log")
+log_level = "info"
+capture_output = True
+
+# Worker initialization hook to ensure scheduler starts only once
+def on_starting(server):
+    """Called just before the master process is initialized."""
+    print("[GUNICORN] Starting Inventarsystem with scheduler support (1 worker only)")
+
+def when_ready(server):
+    """Called just after the server is started."""
+    print("[GUNICORN] Server is ready. Scheduler should be active in the single worker process.")
+
+# Ensure the logs directory exists
+os.makedirs(PROJECT_ROOT / "logs", exist_ok=True)