app/django/utils/decorators.py
author Sverre Rabbelier <srabbelier@gmail.com>
Sun, 01 Feb 2009 22:48:48 +0000
changeset 1166 558bd62ee9d4
parent 54 03e267d67478
permissions -rw-r--r--
Fix get args construction when there are multiple lists on the page It is now possible to go back and forward through the liast, and specify the limit (both offset and limit can be done per list). The JS driving the list boxes is buggy, if visiting an url like: http://localhost:8080/notification/list?limit_0=10 And then change the limit in the second checkbox, it directs to: http://localhost:8080/notification/list?limit_1=25 Whereas it should redirect to: http://localhost:8080/notification/list?limit_0=10&limit_1=25 The logic _does_ work properly when the limit of the changed list is already present in the url. Patch by: Sverre Rabbelier

"Functions that help with dynamically creating decorators for views."

import types
try:
    from functools import wraps
except ImportError:
    from django.utils.functional import wraps  # Python 2.3, 2.4 fallback.

def decorator_from_middleware(middleware_class):
    """
    Given a middleware class (not an instance), returns a view decorator. This
    lets you use middleware functionality on a per-view basis.
    """
    def _decorator_from_middleware(*args, **kwargs):
        # For historical reasons, these "decorators" are also called as
        # dec(func, *args) instead of dec(*args)(func). We handle both forms
        # for backwards compatibility.
        has_func = True
        try:
            view_func = kwargs.pop('view_func')
        except KeyError:
            if len(args):
                view_func, args = args[0], args[1:]
            else:
                has_func = False
        if not (has_func and isinstance(view_func, types.FunctionType)):
            # We are being called as a decorator.
            if has_func:
                args = (view_func,) + args
            middleware = middleware_class(*args, **kwargs)

            def decorator_func(fn):
                return _decorator_from_middleware(fn, *args, **kwargs)
            return decorator_func

        middleware = middleware_class(*args, **kwargs)

        def _wrapped_view(request, *args, **kwargs):
            if hasattr(middleware, 'process_request'):
                result = middleware.process_request(request)
                if result is not None:
                    return result
            if hasattr(middleware, 'process_view'):
                result = middleware.process_view(request, view_func, args, kwargs)
                if result is not None:
                    return result
            try:
                response = view_func(request, *args, **kwargs)
            except Exception, e:
                if hasattr(middleware, 'process_exception'):
                    result = middleware.process_exception(request, e)
                    if result is not None:
                        return result
                raise
            if hasattr(middleware, 'process_response'):
                result = middleware.process_response(request, response)
                if result is not None:
                    return result
            return response
        return wraps(view_func)(_wrapped_view)
    return _decorator_from_middleware