django-downloadview/django_downloadview/decorators.py

"""View decorators.

See also decorators provided by server-specific modules, such as
:py:func:`django_downloadview.nginx.x_accel_redirect`.

"""


class DownloadDecorator(object):
    """View decorator factory to apply middleware to ``view_func`` response.

    Middleware instance is built from ``middleware_factory`` with ``*args`` and
    ``**kwargs``. Middleware factory is typically a class, such as some
    :py:class:`django_downloadview.middlewares.XAccelMiddleware` subclass.

    Response is built from view, then the middleware's ``process_response``
    method is applied on response.

    """
    def __init__(self, middleware_factory):
        """Create a download view decorator."""
        self.middleware_factory = middleware_factory

    def __call__(self, view_func, *middleware_args, **middleware_kwargs):
        """Return ``view_func`` decorated with response middleware."""
        def decorated(request, *view_args, **view_kwargs):
            """Return view's response modified by middleware."""
            response = view_func(request, *view_args, **view_kwargs)
            middleware = self.middleware_factory(*middleware_args,
                                                 **middleware_kwargs)
            return middleware.process_response(request, response)
        return decorated