__init__.py 文件源码

def resolve(self, host, port, family):
        """Return list of (family, address) pairs."""
        child_gr = greenlet.getcurrent()
        main = child_gr.parent
        assert main is not None, "Should be on child greenlet"

        def handler(exc_typ, exc_val, exc_tb):
            # If netutil.Resolver is configured to use TwistedResolver.
            if DomainError and issubclass(exc_typ, DomainError):
                exc_typ = socket.gaierror
                exc_val = socket.gaierror(str(exc_val))

            # Depending on the resolver implementation, we could be on any
            # thread or greenlet. Return to the loop's thread and raise the
            # exception on the calling greenlet from there.
            self.io_loop.add_callback(functools.partial(
                child_gr.throw, exc_typ, exc_val, exc_tb))

            return True  # Don't propagate the exception.

        with stack_context.ExceptionStackContext(handler):
            self.resolver.resolve(host, port, family, callback=child_gr.switch)

        return main.switch()