[Twisted-Python] an easy twisted application question

[Moshe Zadka]

On Tue, 11 Nov 2003, "Phil Christensen" <phil at bubblehouse.org> wrote:

> class InnerSpaceRealm:
>     __implements__ = portal.IRealm
> 
>     def requestAvatar(self, avatarId, mind, *interfaces):
>         if pb.IPerspective in interfaces:
>             registry = ### how do i get this?
>             avatar = UserPerspective(mind, registry.get(avatarId))
>             return pb.IPerspective, avatar, avatar.logout
>         else:
>             raise NotImplementedError("no interface")
> 
> what's the right way to get that service object?

Others have already said that the right way is to "push, not pull":
give the service object as an argument to __init__.
I wanted to add that the correct way to pass the registry to
UserPerspective is probably much the same thing:

class UserPerspective:
    # ...
    def setRegistry(self, registry):
        self.registry = registry

class InnerSpaceRealm:
    __implements__ = portal.IRealm
    def __init__(self, registry):
        self.registry = registry

    def requestAvatar(self, avatarId, mind, *interfaces):
        if pb.IPerspective in interfaces:
            avatar = UserPerspective(mind, self.registry.get(avatarId))
            avatar.setRegistry(self.registry)
            return pb.IPerspective, avatar, avatar.logout
        else:
            raise NotImplementedError("no interface")