Flask resource with http method logic injection capability

injectable_resource.py

from functools import wraps
from flask_restplus import Resource

HTTP_METHODS = ["get", "post", "delete", "put", "patch"]


class InjectableResource(Resource):

	def hook_all_http_methods(self, pre_execution=None, post_execution=None, exception_handler=None):
		for method in HTTP_METHODS:
			self.register_hook(method, pre_execution, post_execution, exception_handler)

	def register_hook(self, method, pre_execution=None, post_execution=None, exception_handler=None):
		"""
		Create new hook to decorate requests

		:param method: http method (GET/POST ..)
		:param pre_execution: decorator to run before the exeuction of this method, will accept wrapped func as parameter
		:param post_execution: decorator to run after the exeuction of this method, will accept wrapped func and return value as parameters
		:param exception_handler: decorator to run in case of exeuction exception, will accept wrapped func and exception as parameters
		"""

		def wrap_with_hook_dec(fn, hook_pre, hook_post, hook_exception):
			@wraps(fn)
			def real_dec(*args, **kwargs):
				result = None
				try:
					if hook_pre:
						hook_pre(fn, args, kwargs)
					result = fn(*args, **kwargs)
					return result
				except Exception as ex:
					if hook_exception:
						hook_exception(fn, ex)
					raise
				finally:
					if hook_post:
						hook_post(fn, result, args, kwargs)

			return real_dec

		if hasattr(self, method):
			setattr(self, method, wrap_with_hook_dec(getattr(self, method), pre_execution, post_execution, exception_handler))

# example usage:

class LocaleResource(InjectableResource):
	"""Wrapper to set up locale attribute according to request headers"""

	__language_options__ = ['en', 'he']

	def __init__(self, *args, **kwargs):
		super(LocaleResource, self).__init__(*args, **kwargs)
		self.locale = None
		self.hook_all_http_methods(self.language_hook)

	def language_hook(self, fn, args, kwargs):
		self.locale = request.accept_languages.best_match(self.__language_options__) or "en"