""" REST API Views for Notifications Application This module contains Django REST Framework views for managing notifications, channels, templates, and rules through a RESTful API. """ from rest_framework import viewsets, status, permissions from rest_framework.decorators import api_view, permission_classes, action from rest_framework.response import Response from django_filters.rest_framework import DjangoFilterBackend from django.utils import timezone from django.db.models import Count, Avg from datetime import timedelta from ..models import NotificationChannel, NotificationTemplate, Notification, NotificationRule from ..services import NotificationService from ..tasks import process_notification, send_notification_via_rule from apps.core.throttling import NotificationAPIThrottle from .serializers import ( NotificationChannelSerializer, NotificationTemplateSerializer, NotificationSerializer, NotificationRuleSerializer, NotificationStatsSerializer ) class NotificationChannelViewSet(viewsets.ModelViewSet): """ ViewSet for managing notification channels. Provides CRUD operations for notification channels with configuration validation and testing capabilities. """ queryset = NotificationChannel.objects.all().select_related('created_by') serializer_class = NotificationChannelSerializer permission_classes = [permissions.IsAuthenticated] throttle_classes = [NotificationAPIThrottle] filter_backends = [DjangoFilterBackend] filterset_fields = ['channel_type', 'is_active'] ordering_fields = ['name', 'created_at'] ordering = ['name'] def perform_create(self, serializer): """Set the current user as the channel creator.""" serializer.save(created_by=self.request.user) @action(detail=True, methods=['post']) def test(self, request, pk=None): """Send a test notification through this channel.""" channel = self.get_object() try: notification_service = NotificationService() success = notification_service.send_test_notification(channel) if success: return Response({ 'success': True, 'message': f'Test notification sent via {channel.name}' }) else: return Response({ 'success': False, 'error': 'Failed to send test notification' }, status=status.HTTP_400_BAD_REQUEST) except Exception as e: return Response({ 'success': False, 'error': str(e) }, status=status.HTTP_500_INTERNAL_SERVER_ERROR) class NotificationTemplateViewSet(viewsets.ModelViewSet): """ ViewSet for managing notification templates. Provides CRUD operations for templates with usage statistics and validation capabilities. """ queryset = NotificationTemplate.objects.all() serializer_class = NotificationTemplateSerializer permission_classes = [permissions.IsAuthenticated] throttle_classes = [NotificationAPIThrottle] filter_backends = [DjangoFilterBackend] filterset_fields = ['template_type', 'is_active'] search_fields = ['name', 'template_type'] ordering_fields = ['name', 'created_at'] ordering = ['name'] @action(detail=True, methods=['get']) def preview(self, request, pk=None): """Preview template with sample data.""" template = self.get_object() # Sample context data for preview sample_context = { 'channel_name': 'Sample Channel', 'jingle_name': 'Sample Jingle', 'confidence_score': 0.95, 'detection_time': timezone.now(), 'duration_seconds': 30, 'region': 'US-EAST' } try: rendered_subject = template.render_subject(sample_context) rendered_message = template.render_message(sample_context) return Response({ 'subject': rendered_subject, 'message': rendered_message, 'sample_context': sample_context }) except Exception as e: return Response({ 'error': f'Template rendering failed: {str(e)}' }, status=status.HTTP_400_BAD_REQUEST) class NotificationViewSet(viewsets.ModelViewSet): """ ViewSet for managing notifications. Provides access to notification history with filtering and retry capabilities. """ queryset = Notification.objects.all().select_related( 'channel', 'template' ) serializer_class = NotificationSerializer permission_classes = [permissions.IsAuthenticated] throttle_classes = [NotificationAPIThrottle] filter_backends = [DjangoFilterBackend] filterset_fields = ['status', 'channel', 'template'] ordering_fields = ['created_at', 'sent_at'] ordering = ['-created_at'] @action(detail=True, methods=['post']) def retry(self, request, pk=None): """Retry a failed notification.""" notification = self.get_object() if not notification.can_retry(): return Response({ 'error': 'Notification cannot be retried' }, status=status.HTTP_400_BAD_REQUEST) try: # Queue for retry task = process_notification.delay(str(notification.id)) return Response({ 'success': True, 'message': 'Notification queued for retry', 'task_id': task.id }, status=status.HTTP_202_ACCEPTED) except Exception as e: return Response({ 'error': str(e) }, status=status.HTTP_500_INTERNAL_SERVER_ERROR) @action(detail=False, methods=['get']) def statistics(self, request): """Get notification system statistics.""" # Time ranges now = timezone.now() last_24h = now - timedelta(hours=24) last_7d = now - timedelta(days=7) # Basic counts total_notifications = self.queryset.count() notifications_24h = self.queryset.filter(created_at__gte=last_24h).count() sent_notifications = self.queryset.filter(status='completed').count() failed_notifications = self.queryset.filter(status='failed').count() pending_notifications = self.queryset.filter(status='pending').count() # Delivery rate delivery_rate = 0 if total_notifications > 0: delivery_rate = (sent_notifications / total_notifications) * 100 # Average delivery time completed_notifications = self.queryset.filter( status='completed', sent_at__isnull=False ) avg_delivery_time = 0 if completed_notifications.exists(): delivery_times = [] for notification in completed_notifications: if notification.sent_at and notification.created_at: delta = notification.sent_at - notification.created_at delivery_times.append(delta.total_seconds()) if delivery_times: avg_delivery_time = sum(delivery_times) / len(delivery_times) # Channel performance channel_performance = {} for channel in NotificationChannel.objects.filter(is_active=True): channel_notifications = self.queryset.filter(channel=channel) total = channel_notifications.count() sent = channel_notifications.filter(status='completed').count() channel_performance[channel.name] = { 'total': total, 'sent': sent, 'success_rate': (sent / total * 100) if total > 0 else 0 } # Recent activity recent_activity = list( self.queryset.filter( created_at__gte=last_24h ).order_by('-created_at')[:10].values( 'channel__name', 'template__name', 'status', 'created_at', 'sent_at' ) ) stats_data = { 'total_notifications': total_notifications, 'sent_notifications': sent_notifications, 'failed_notifications': failed_notifications, 'pending_notifications': pending_notifications, 'delivery_rate': round(delivery_rate, 2), 'avg_delivery_time': round(avg_delivery_time, 2), 'channel_performance': channel_performance, 'recent_activity': recent_activity } serializer = NotificationStatsSerializer(stats_data) return Response(serializer.data) class NotificationRuleViewSet(viewsets.ModelViewSet): """ ViewSet for managing notification rules. Provides CRUD operations for rules with testing and activation capabilities. """ queryset = NotificationRule.objects.all().select_related( 'channel', 'template' ) serializer_class = NotificationRuleSerializer permission_classes = [permissions.IsAuthenticated] throttle_classes = [NotificationAPIThrottle] filter_backends = [DjangoFilterBackend] filterset_fields = ['event_type', 'is_active', 'channel'] ordering_fields = ['name', 'priority', 'created_at'] ordering = ['priority', 'name'] @action(detail=True, methods=['post']) def test(self, request, pk=None): """Test a notification rule with sample data.""" rule = self.get_object() # Sample context for testing sample_context = { 'channel_name': 'Test Channel', 'event_type': rule.event_type, 'timestamp': timezone.now(), 'test_mode': True } try: # Send test notification task = send_notification_via_rule.delay( event_type=rule.event_type, context=sample_context ) return Response({ 'success': True, 'message': f'Test notification sent for rule: {rule.name}', 'task_id': task.id }, status=status.HTTP_202_ACCEPTED) except Exception as e: return Response({ 'error': str(e) }, status=status.HTTP_500_INTERNAL_SERVER_ERROR) @api_view(['POST']) @permission_classes([permissions.IsAuthenticated]) def send_notification(request): """ API endpoint to send custom notifications. Allows sending notifications with custom content through specified channels and templates. """ required_fields = ['channel_id', 'template_id', 'context'] # Validate required fields for field in required_fields: if field not in request.data: return Response({ 'error': f'Missing required field: {field}' }, status=status.HTTP_400_BAD_REQUEST) try: # Get channel and template channel = NotificationChannel.objects.get(id=request.data['channel_id']) template = NotificationTemplate.objects.get(id=request.data['template_id']) # Create notification notification = Notification.objects.create( channel=channel, template=template, context=request.data['context'], scheduled_at=request.data.get('scheduled_at', timezone.now()) ) # Queue for processing task = process_notification.delay(str(notification.id)) return Response({ 'success': True, 'notification_id': str(notification.id), 'task_id': task.id }, status=status.HTTP_202_ACCEPTED) except (NotificationChannel.DoesNotExist, NotificationTemplate.DoesNotExist) as e: return Response({ 'error': 'Channel or template not found' }, status=status.HTTP_404_NOT_FOUND) except Exception as e: return Response({ 'error': str(e) }, status=status.HTTP_500_INTERNAL_SERVER_ERROR) @api_view(['GET']) @permission_classes([permissions.IsAuthenticated]) def live_notifications(request): """ API endpoint for live notification updates. Returns recent notifications for real-time dashboard updates. """ # Get recent notifications from last 5 minutes recent_time = timezone.now() - timedelta(minutes=5) recent_notifications = Notification.objects.filter( created_at__gte=recent_time ).select_related('channel', 'template').order_by('-created_at')[:20] serializer = NotificationSerializer(recent_notifications, many=True) return Response(serializer.data)