""" Download System Stress Testing. This module tests the download queue and management system under heavy load and stress conditions. """ import asyncio from typing import List from unittest.mock import AsyncMock, Mock, patch import pytest from src.server.services.download_service import DownloadService, get_download_service @pytest.mark.performance class TestDownloadQueueStress: """Stress testing for download queue.""" @pytest.fixture def mock_series_app(self): """Create mock SeriesApp.""" app = Mock() app.download_episode = AsyncMock(return_value={"success": True}) app.get_download_progress = Mock(return_value=50.0) return app @pytest.fixture async def download_service(self, mock_series_app): """Create download service with mock.""" with patch( "src.server.services.download_service.SeriesApp", return_value=mock_series_app, ): service = DownloadService() yield service @pytest.mark.asyncio async def test_concurrent_download_additions( self, download_service ): """Test adding many downloads concurrently.""" num_downloads = 100 # Add downloads concurrently tasks = [ download_service.add_to_queue( anime_id=i, episode_number=1, priority=5, ) for i in range(num_downloads) ] results = await asyncio.gather(*tasks, return_exceptions=True) # Count successful additions successful = sum( 1 for r in results if not isinstance(r, Exception) ) # Should handle at least 90% successfully success_rate = (successful / num_downloads) * 100 assert ( success_rate >= 90.0 ), f"Queue addition success rate too low: {success_rate}%" @pytest.mark.asyncio async def test_queue_capacity(self, download_service): """Test queue behavior at capacity.""" # Fill queue beyond reasonable capacity num_downloads = 1000 for i in range(num_downloads): try: await download_service.add_to_queue( anime_id=i, episode_number=1, priority=5, ) except Exception: # Queue might have limits pass # Queue should still be functional queue = await download_service.get_queue() assert queue is not None, "Queue became non-functional" @pytest.mark.asyncio async def test_rapid_queue_operations(self, download_service): """Test rapid add/remove operations.""" num_operations = 200 operations = [] for i in range(num_operations): if i % 2 == 0: # Add operation operations.append( download_service.add_to_queue( anime_id=i, episode_number=1, priority=5, ) ) else: # Remove operation operations.append( download_service.remove_from_queue(i - 1) ) results = await asyncio.gather( *operations, return_exceptions=True ) # Most operations should succeed successful = sum( 1 for r in results if not isinstance(r, Exception) ) success_rate = (successful / num_operations) * 100 assert success_rate >= 80.0, "Operation success rate too low" @pytest.mark.asyncio async def test_concurrent_queue_reads(self, download_service): """Test concurrent queue status reads.""" # Add some items to queue for i in range(10): await download_service.add_to_queue( anime_id=i, episode_number=1, priority=5, ) # Perform many concurrent reads num_reads = 100 tasks = [ download_service.get_queue() for _ in range(num_reads) ] results = await asyncio.gather(*tasks, return_exceptions=True) # All reads should succeed successful = sum( 1 for r in results if not isinstance(r, Exception) ) assert ( successful == num_reads ), "Some queue reads failed" @pytest.mark.performance class TestDownloadMemoryUsage: """Test memory usage under load.""" @pytest.mark.asyncio async def test_queue_memory_leak(self): """Test for memory leaks in queue operations.""" # This is a placeholder for memory profiling # In real implementation, would use memory_profiler # or similar tools service = get_download_service() # Perform many operations for i in range(1000): await service.add_to_queue( anime_id=i, episode_number=1, priority=5, ) if i % 100 == 0: # Clear some items periodically await service.remove_from_queue(i) # Service should still be functional queue = await service.get_queue() assert queue is not None @pytest.mark.performance class TestDownloadConcurrency: """Test concurrent download handling.""" @pytest.fixture def mock_series_app(self): """Create mock SeriesApp.""" app = Mock() async def slow_download(*args, **kwargs): # Simulate slow download await asyncio.sleep(0.1) return {"success": True} app.download_episode = slow_download app.get_download_progress = Mock(return_value=50.0) return app @pytest.mark.asyncio async def test_concurrent_download_execution( self, mock_series_app ): """Test executing multiple downloads concurrently.""" with patch( "src.server.services.download_service.SeriesApp", return_value=mock_series_app, ): service = DownloadService() # Start multiple downloads num_downloads = 20 tasks = [ service.add_to_queue( anime_id=i, episode_number=1, priority=5, ) for i in range(num_downloads) ] await asyncio.gather(*tasks) # All downloads should be queued queue = await service.get_queue() assert len(queue) <= num_downloads @pytest.mark.asyncio async def test_download_priority_under_load( self, mock_series_app ): """Test that priority is respected under load.""" with patch( "src.server.services.download_service.SeriesApp", return_value=mock_series_app, ): service = DownloadService() # Add downloads with different priorities await service.add_to_queue( anime_id=1, episode_number=1, priority=1 ) await service.add_to_queue( anime_id=2, episode_number=1, priority=10 ) await service.add_to_queue( anime_id=3, episode_number=1, priority=5 ) # High priority should be processed first queue = await service.get_queue() assert queue is not None @pytest.mark.performance class TestDownloadErrorHandling: """Test error handling under stress.""" @pytest.mark.asyncio async def test_multiple_failed_downloads(self): """Test handling of many failed downloads.""" # Mock failing downloads mock_app = Mock() mock_app.download_episode = AsyncMock( side_effect=Exception("Download failed") ) with patch( "src.server.services.download_service.SeriesApp", return_value=mock_app, ): service = DownloadService() # Add multiple downloads for i in range(50): await service.add_to_queue( anime_id=i, episode_number=1, priority=5, ) # Service should remain stable despite failures queue = await service.get_queue() assert queue is not None @pytest.mark.asyncio async def test_recovery_from_errors(self): """Test system recovery after errors.""" service = get_download_service() # Cause some errors try: await service.remove_from_queue(99999) except Exception: pass try: await service.add_to_queue( anime_id=-1, episode_number=-1, priority=5, ) except Exception: pass # System should still work await service.add_to_queue( anime_id=1, episode_number=1, priority=5, ) queue = await service.get_queue() assert queue is not None