refactor: Implement base model routes and services for LoRA and Checkpoint

- Added BaseModelRoutes class to handle common routes and logic for model types.
- Created CheckpointRoutes class inheriting from BaseModelRoutes for checkpoint-specific routes.
- Implemented CheckpointService class for handling checkpoint-related data and operations.
- Developed LoraService class for managing LoRA-specific functionalities.
- Introduced ModelServiceFactory to manage service and route registrations for different model types.
- Established methods for fetching, filtering, and formatting model data across services.
- Integrated CivitAI metadata handling within model routes and services.
- Added pagination and filtering capabilities for model data retrieval.

py/services/model_service_factory.py

@@ -0,0 +1,137 @@
+from typing import Dict, Type, Any
+import logging
+
+logger = logging.getLogger(__name__)
+
+class ModelServiceFactory:
+    """Factory for managing model services and routes"""
+    
+    _services: Dict[str, Type] = {}
+    _routes: Dict[str, Type] = {}
+    _initialized_services: Dict[str, Any] = {}
+    _initialized_routes: Dict[str, Any] = {}
+    
+    @classmethod
+    def register_model_type(cls, model_type: str, service_class: Type, route_class: Type):
+        """Register a new model type with its service and route classes
+        
+        Args:
+            model_type: The model type identifier (e.g., 'lora', 'checkpoint')
+            service_class: The service class for this model type
+            route_class: The route class for this model type
+        """
+        cls._services[model_type] = service_class
+        cls._routes[model_type] = route_class
+        logger.info(f"Registered model type '{model_type}' with service {service_class.__name__} and routes {route_class.__name__}")
+    
+    @classmethod
+    def get_service_class(cls, model_type: str) -> Type:
+        """Get service class for a model type
+        
+        Args:
+            model_type: The model type identifier
+            
+        Returns:
+            The service class for the model type
+            
+        Raises:
+            ValueError: If model type is not registered
+        """
+        if model_type not in cls._services:
+            raise ValueError(f"Unknown model type: {model_type}")
+        return cls._services[model_type]
+    
+    @classmethod
+    def get_route_class(cls, model_type: str) -> Type:
+        """Get route class for a model type
+        
+        Args:
+            model_type: The model type identifier
+            
+        Returns:
+            The route class for the model type
+            
+        Raises:
+            ValueError: If model type is not registered
+        """
+        if model_type not in cls._routes:
+            raise ValueError(f"Unknown model type: {model_type}")
+        return cls._routes[model_type]
+    
+    @classmethod
+    def get_route_instance(cls, model_type: str):
+        """Get or create route instance for a model type
+        
+        Args:
+            model_type: The model type identifier
+            
+        Returns:
+            The route instance for the model type
+        """
+        if model_type not in cls._initialized_routes:
+            route_class = cls.get_route_class(model_type)
+            cls._initialized_routes[model_type] = route_class()
+        return cls._initialized_routes[model_type]
+    
+    @classmethod
+    def setup_all_routes(cls, app):
+        """Setup routes for all registered model types
+        
+        Args:
+            app: The aiohttp application instance
+        """
+        logger.info(f"Setting up routes for {len(cls._services)} registered model types")
+        
+        for model_type in cls._services.keys():
+            try:
+                routes_instance = cls.get_route_instance(model_type)
+                routes_instance.setup_routes(app)
+                logger.info(f"Successfully set up routes for {model_type}")
+            except Exception as e:
+                logger.error(f"Failed to setup routes for {model_type}: {e}", exc_info=True)
+    
+    @classmethod
+    def get_registered_types(cls) -> list:
+        """Get list of all registered model types
+        
+        Returns:
+            List of registered model type identifiers
+        """
+        return list(cls._services.keys())
+    
+    @classmethod
+    def is_registered(cls, model_type: str) -> bool:
+        """Check if a model type is registered
+        
+        Args:
+            model_type: The model type identifier
+            
+        Returns:
+            True if the model type is registered, False otherwise
+        """
+        return model_type in cls._services
+    
+    @classmethod
+    def clear_registrations(cls):
+        """Clear all registrations - mainly for testing purposes"""
+        cls._services.clear()
+        cls._routes.clear()
+        cls._initialized_services.clear()
+        cls._initialized_routes.clear()
+        logger.info("Cleared all model type registrations")
+
+
+def register_default_model_types():
+    """Register the default model types (LoRA and Checkpoint)"""
+    from ..services.lora_service import LoraService
+    from ..services.checkpoint_service import CheckpointService
+    from ..routes.lora_routes import LoraRoutes
+    from ..routes.checkpoint_routes import CheckpointRoutes
+    
+    # Register LoRA model type
+    ModelServiceFactory.register_model_type('lora', LoraService, LoraRoutes)
+    
+    # Register Checkpoint model type
+    ModelServiceFactory.register_model_type('checkpoint', CheckpointService, CheckpointRoutes)
+    
+    logger.info("Registered default model types: lora, checkpoint")