Ticket #356: rpcdispatch.py

from django.conf import settings

class Dispatcher:
        """
        This class encapsulates a dispatcher. This is used to build
        the real table needed for the RPC method dispatch. An instance
        of this class is returned by the dispatch and include functions.
        """
        def __init__(self, base, module=None, entries=None):
                self.dispatch = {}
                if module is None and entries is None:
                        raise ValueError('either module or entries needs to be specified')
                if entries is None:
                        module = __import__(module, '', '', [''])
                        self.dispatch.update(module.rpccalls.dispatch)
                else:
                        for el in entries:
                                if type(el) == tuple:
                                        (fn, fc) = el
                                        if base: fc = '%s.%s' % (base, fc)
                                        p = fc.rfind('.')
                                        modname = fc[:p]
                                        funcname = fc[p+1:]
                                        self.dispatch[fn] = getattr(__import__(modname, '', '', ['']), funcname)
                                elif isinstance(el, Dispatcher):
                                        self.dispatch.update(el.dispatch)

        def find(self, function):
                """
                This method searches for a matching function definition.
                """
                return self.dispatch.get(function, None)

def dispatch(base, *entries):
        return Dispatcher(base, entries=entries)

def include(module):
        return Dispatcher('', module=module)

dispatch_table = None
def dispatcher():
        global dispatch_table
        if dispatch_table is None:
                dispatch_table = include(settings.ROOT_RPCCONF)
        return dispatch_table

if __name__ == '__main__':
        print dispatcher().dispatch