Reflection

As the library heavily relies on type introspection of classes and methods, a utility class TypeDescriptor is available that covers type information on classes.

After being instantiated with

TypeDescriptor.for_type(<type>)

it offers the methods

• get_methods(local=False)
  return a list of either local or overall methods
• get_method(name: str, local=False)
  return a single either local or overall method
• has_decorator(decorator: Callable) -> bool
  return True, if the class is decorated with the specified decorator
• get_decorator(decorator) -> Optional[DecoratorDescriptor]
  return a descriptor covering the decorator. In addition to the callable, it also stores the supplied args in the args property

The returned method descriptors provide:

• param_types
  list of arg types
• return_type
  the return type
• has_decorator(decorator: Callable) -> bool return True, if the method is decorated with the specified decorator
• get_decorator(decorator: Callable) -> Optional[DecoratorDescriptor]
  return a descriptor covering the decorator. In addition to the callable, it also stores the supplied args in the args property

The management of decorators in turn relies on another utility class Decorators that caches decorators.

Whenver you define a custom decorator, you will need to register it accordingly.

Example:

def transactional(scope):
    def decorator(func):
        Decorators.add(func, transactional, scope) # also add _all_ parameters in order to cache them
        return func

    return decorator