authentication_decorator.py

#!/usr/bin/python
import json

class AuthenticationException( Exception ):
        pass

def loginrequired( fn ):
        def wrapper( *args, **kwargs ):
                print "args:",args
                print "kwargs:",kwargs

                j = args[1]
                if not j['authenticated']:
                        raise AuthenticationException( "Not authenticated" )

                fn( *args, **kwargs )
        return wrapper

class foo:
        def __init__(self):
                pass

        @loginrequired
        def process_json(self, JSON=json):
                print "I would process some json here"

jsonstrings = [ '{ "foo": "bar", "authenticated": 1 }',
                '{ "foo": "bar", "authenticated": 0 }',
]

f = foo()

for s in jsonstrings:
        print "Processing: %s" % ( s )
        jsonobj = json.loads( s )
        f.process_json( jsonobj )