Add Exception Handling Decorator and Registry Classes

Introduce a new decorator for exception handling and a registry to manage exception handlers. The decorator allows for the registration of handlers for specific exception types, enhancing error management capabilities in the application.

Author: William-W-Chen

py_spring_core/exception_handler/decorator.py

@@ -0,0 +1,18 @@
+
+
+from functools import wraps
+from typing import Any, Callable, Type
+
+
+from py_spring_core.exception_handler.exception_handler_registry import ExceptionHandlerRegistry
+
+
+def ExceptionHandler(exception_cls: Type[Exception]) -> Callable[[Callable[[Exception], Any]], Callable]:
+    def decorator(func: Callable[[Exception], Any]) -> Callable:
+        @wraps(func)
+        def wrapper(*args, **kwargs) -> Any:
+            return func(*args, **kwargs)
+        ExceptionHandlerRegistry.register(exception_cls, wrapper)
+        return wrapper
+    
+    return decorator

py_spring_core/exception_handler/exception_handler_registry.py

@@ -0,0 +1,25 @@
+
+
+from typing import Any, Callable, Type, TypeVar
+
+from loguru import logger
+
+E = TypeVar('E', bound=Exception)
+
+class ExceptionHandlerRegistry:
+    _handlers: dict[str, Callable[[Any], Any]] = {}
+
+    @classmethod
+    def register(cls, exception_cls: Type[E], handler: Callable[[E], Any]):
+        key = exception_cls.__name__
+        logger.debug(f"Registering exception handler for {key}: {handler.__name__}")
+        if key in cls._handlers:
+            error_message = f"Exception handler for {exception_cls} already registered"
+            logger.error(error_message)
+            raise RuntimeError(error_message)
+        
+        cls._handlers[exception_cls.__name__] = handler
+
+    @classmethod
+    def get_handler(cls, exception_cls: Type[E]) -> Callable[[E], Any]:
+        return cls._handlers[exception_cls.__name__]