caresresolver.py 文件源码

def resolve(self, host, port, family=0):
        if is_valid_ip(host):
            addresses = [host]
        else:
            # gethostbyname doesn't take callback as a kwarg
            self.channel.gethostbyname(host, family, (yield gen.Callback(1)))
            callback_args = yield gen.Wait(1)
            assert isinstance(callback_args, gen.Arguments)
            assert not callback_args.kwargs
            result, error = callback_args.args
            if error:
                raise Exception('C-Ares returned error %s: %s while resolving %s' %
                                (error, pycares.errno.strerror(error), host))
            addresses = result.addresses
        addrinfo = []
        for address in addresses:
            if '.' in address:
                address_family = socket.AF_INET
            elif ':' in address:
                address_family = socket.AF_INET6
            else:
                address_family = socket.AF_UNSPEC
            if family != socket.AF_UNSPEC and family != address_family:
                raise Exception('Requested socket family %d but got %d' %
                                (family, address_family))
            addrinfo.append((address_family, (address, port)))
        raise gen.Return(addrinfo)