rlkit/envs/proxy_env.py

from gym import Env


class ProxyEnv(Env):
    def __init__(self, wrapped_env):
        self._wrapped_env = wrapped_env
        self.action_space = self._wrapped_env.action_space
        self.observation_space = self._wrapped_env.observation_space

    @property
    def wrapped_env(self):
        return self._wrapped_env

    def reset(self, **kwargs):
        return self._wrapped_env.reset(**kwargs)

    def step(self, action):
        return self._wrapped_env.step(action)

    def render(self, *args, **kwargs):
        return self._wrapped_env.render(*args, **kwargs)

    @property
    def horizon(self):
        return self._wrapped_env.horizon

    def terminate(self):
        if hasattr(self.wrapped_env, "terminate"):
            self.wrapped_env.terminate()

    def __getattr__(self, attr):
        if attr == '_wrapped_env':
            raise AttributeError()
        return getattr(self._wrapped_env, attr)

    def __getstate__(self):
        """
        This is useful to override in case the wrapped env has some funky
        __getstate__ that doesn't play well with overriding __getattr__.
        The main problematic case is/was gym's EzPickle serialization scheme.
        :return:
        """
        return self.__dict__

    def __setstate__(self, state):
        self.__dict__.update(state)

    def __str__(self):
        return '{}({})'.format(type(self).__name__, self.wrapped_env)