django-rest-framework/djangorestframework/decorators.py

from functools import wraps
from django.http import Http404
from django.utils.decorators import available_attrs
from django.core.exceptions import PermissionDenied
from djangorestframework import exceptions
from djangorestframework import status
from djangorestframework.response import Response
from djangorestframework.request import Request


def api_view(allowed_methods):
    """
    Decorator to make a view only accept particular request methods.  Usage::

        @api_view(['GET', 'POST'])
        def my_view(request):
            # request will be an instance of `Request`
            # APIException instances will be handled

    Note that request methods should be in uppercase.
    """
    allowed_methods = [method.upper() for method in allowed_methods]

    def decorator(func):
        @wraps(func, assigned=available_attrs(func))
        def inner(request, *args, **kwargs):
            try:
                request = Request(request)
                if request.method not in allowed_methods:
                    return exceptions.MethodNotAllowed(request.method)
                response = func(request, *args, **kwargs)
                response.request = request
                return response
            except exceptions.APIException as exc:
                return Response({'detail': exc.detail}, status=exc.status_code)
            except Http404 as exc:
                return Response({'detail': 'Not found'},
                                status=status.HTTP_404_NOT_FOUND)
            except PermissionDenied as exc:
                return Response({'detail': 'Permission denied'},
                                status=status.HTTP_403_FORBIDDEN)
        return inner
    return decorator