Source code for torchrl.envs.utils
# Copyright (c) Meta Platforms, Inc. and affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.
from __future__ import annotations
import abc
import contextlib
import functools
import importlib.util
import inspect
import os
import re
import warnings
from enum import Enum
from typing import Any, Dict, List, Union
import tensordict
import torch
from tensordict import (
is_tensor_collection,
LazyStackedTensorDict,
TensorDict,
TensorDictBase,
unravel_key,
)
from tensordict.base import _is_leaf_nontensor
from tensordict.nn import TensorDictModule, TensorDictModuleBase
from tensordict.nn.probabilistic import ( # noqa
# Note: the `set_interaction_mode` and their associated arg `default_interaction_mode` are being deprecated!
# Please use the `set_/interaction_type` ones above with the InteractionType enum instead.
# See more details: https://github.com/pytorch/rl/issues/1016
interaction_mode as exploration_mode,
interaction_type as exploration_type,
InteractionType as ExplorationType,
set_interaction_mode as set_exploration_mode,
set_interaction_type as set_exploration_type,
)
from tensordict.utils import NestedKey
from torch import nn as nn
from torch.utils._pytree import tree_map
from torchrl._utils import _replace_last, _rng_decorator, logger as torchrl_logger
from torchrl.data.tensor_specs import (
CompositeSpec,
NO_DEFAULT,
TensorSpec,
UnboundedContinuousTensorSpec,
)
from torchrl.data.utils import check_no_exclusive_keys
__all__ = [
"exploration_mode",
"exploration_type",
"set_exploration_mode",
"set_exploration_type",
"ExplorationType",
"check_env_specs",
"step_mdp",
"make_composite_from_td",
"MarlGroupMapType",
"check_marl_grouping",
]
ACTION_MASK_ERROR = RuntimeError(
"An out-of-bounds actions has been provided to an env with an 'action_mask' output."
" If you are using a custom policy, make sure to take the action mask into account when computing the output."
" If you are using a default policy, please add the torchrl.envs.transforms.ActionMask transform to your environment."
"If you are using a ParallelEnv or another batched inventor, "
"make sure to add the transform to the ParallelEnv (and not to the sub-environments)."
" For more info on using action masks, see the docs at: "
"https://pytorch.org/rl/reference/envs.html#environments-with-masked-actions"
)
def _convert_exploration_type(*, exploration_mode, exploration_type):
if exploration_mode is not None:
return ExplorationType.from_str(exploration_mode)
return exploration_type
class _classproperty(property):
def __get__(self, cls, owner):
return classmethod(self.fget).__get__(None, owner)()
class _StepMDP:
"""Stateful version of step_mdp.
Precomputes the list of keys to include and exclude during a call to step_mdp
to reduce runtime.
"""
def __init__(
self,
env,
*,
keep_other: bool = True,
exclude_reward: bool = True,
exclude_done: bool = False,
exclude_action: bool = True,
):
action_keys = env.action_keys
done_keys = env.done_keys
reward_keys = env.reward_keys
observation_keys = env.full_observation_spec.keys(True, True)
state_keys = env.full_state_spec.keys(True, True)
self.action_keys = [unravel_key(key) for key in action_keys]
self.done_keys = [unravel_key(key) for key in done_keys]
self.observation_keys = list(observation_keys)
self.state_keys = list(state_keys)
self.reward_keys = [unravel_key(key) for key in reward_keys]
self.reward_keys_filt = list(set(self.reward_keys) - set(self.state_keys))
excluded = set()
if exclude_reward:
# If a reward is also a state, it must be in the input
excluded = excluded.union(self.reward_keys_filt)
if exclude_done:
excluded = excluded.union(self.done_keys)
if exclude_action:
excluded = excluded.union(self.action_keys)
self.excluded = [unravel_key(key) for key in excluded]
self.keep_other = keep_other
self.exclude_action = exclude_action
self.exclude_from_root = ["next", *self.done_keys]
self.keys_from_next = list(self.observation_keys)
if not exclude_reward:
self.keys_from_next += self.reward_keys
else:
self.keys_from_next += [
reward_key
for reward_key in self.reward_keys
if reward_key in self.state_keys
]
if not exclude_done:
self.keys_from_next += self.done_keys
self.keys_from_root = []
if not exclude_action:
self.keys_from_root += self.action_keys
else:
self.exclude_from_root += self.action_keys
if keep_other:
self.keys_from_root += self.state_keys
else:
self.exclude_from_root += self.state_keys
reset_keys = {_replace_last(key, "_reset") for key in self.done_keys}
self.exclude_from_root += list(reset_keys)
self.exclude_from_root += self.reward_keys_filt
self.exclude_from_root = self._repr_key_list_as_tree(self.exclude_from_root)
self.keys_from_root = self._repr_key_list_as_tree(self.keys_from_root)
self.keys_from_next = self._repr_key_list_as_tree(self.keys_from_next)
self.validated = None
# Model based envs can have missing keys
# TODO: do we want to always allow this? check_env_specs should catch these or downstream ops
self._allow_absent_keys = True
def validate(self, tensordict):
if self.validated:
return True
if self.validated is None:
# check that the key set of the tensordict matches what is expected
expected = (
self.state_keys
+ self.action_keys
+ self.done_keys
+ self.observation_keys
+ [unravel_key(("next", key)) for key in self.observation_keys]
+ [unravel_key(("next", key)) for key in self.done_keys]
+ [unravel_key(("next", key)) for key in self.reward_keys]
)
def _is_reset(key: NestedKey):
if isinstance(key, str):
return key == "_reset"
return key[-1] == "_reset"
actual = {
key
for key in tensordict.keys(True, True, is_leaf=_is_leaf_nontensor)
if not _is_reset(key)
}
expected = set(expected)
self.validated = expected.intersection(actual) == expected
if not self.validated:
warnings.warn(
"The expected key set and actual key set differ. "
"This will work but with a slower throughput than "
"when the specs match exactly the actual key set "
"in the data. "
f"{{Expected keys}}-{{Actual keys}}={set(expected) - actual}, \n"
f"{{Actual keys}}-{{Expected keys}}={actual- set(expected)}."
)
return self.validated
@staticmethod
def _repr_key_list_as_tree(key_list):
"""Represents the keys as a tree to facilitate iteration."""
if not key_list:
return {}
key_dict = {key: torch.zeros(()) for key in key_list}
td = TensorDict(key_dict, batch_size=torch.Size([]))
return tree_map(lambda x: None, td.to_dict())
@classmethod
def _grab_and_place(
cls,
nested_key_dict: dict,
data_in: TensorDictBase,
data_out: TensorDictBase,
_allow_absent_keys: bool,
):
for key, subdict in nested_key_dict.items():
val = data_in._get_str(key, NO_DEFAULT)
if subdict is not None:
val_out = data_out._get_str(key, None)
if val_out is None:
val_out = val.empty()
if isinstance(val, LazyStackedTensorDict):
val = LazyStackedTensorDict(
*(
cls._grab_and_place(
subdict,
_val,
_val_out,
_allow_absent_keys=_allow_absent_keys,
)
for (_val, _val_out) in zip(
val.unbind(val.stack_dim),
val_out.unbind(val_out.stack_dim),
)
),
stack_dim=val.stack_dim,
)
else:
val = cls._grab_and_place(
subdict, val, val_out, _allow_absent_keys=_allow_absent_keys
)
if val is NO_DEFAULT:
if not _allow_absent_keys:
raise KeyError(f"key {key} not found.")
else:
data_out._set_str(
key, val, validated=True, inplace=False, non_blocking=False
)
return data_out
@classmethod
def _exclude(
cls, nested_key_dict: dict, data_in: TensorDictBase, out: TensorDictBase | None
) -> None:
"""Copies the entries if they're not part of the list of keys to exclude."""
if isinstance(data_in, LazyStackedTensorDict):
if out is None:
out = data_in.empty()
for td, td_out in zip(data_in.tensordicts, out.tensordicts):
cls._exclude(nested_key_dict, td, td_out)
return out
has_set = False
for key, value in data_in.items(is_leaf=tensordict.base._is_leaf_nontensor):
subdict = nested_key_dict.get(key, NO_DEFAULT)
if subdict is NO_DEFAULT:
value = value.copy() if is_tensor_collection(value) else value
if not has_set and out is None:
out = data_in.empty()
out._set_str(key, value, validated=True, inplace=False)
has_set = True
elif subdict is not None:
value = cls._exclude(subdict, value, None)
if value is not None:
if not has_set and out is None:
out = data_in.empty()
out._set_str(key, value, validated=True, inplace=False)
has_set = True
if has_set:
return out
def __call__(self, tensordict):
if isinstance(tensordict, LazyStackedTensorDict):
out = LazyStackedTensorDict.lazy_stack(
[self.__call__(td) for td in tensordict.tensordicts],
tensordict.stack_dim,
)
return out
next_td = tensordict._get_str("next", None)
if self.validate(tensordict):
if self.keep_other:
out = self._exclude(self.exclude_from_root, tensordict, out=None)
else:
out = next_td.empty()
self._grab_and_place(
self.keys_from_root,
tensordict,
out,
_allow_absent_keys=self._allow_absent_keys,
)
self._grab_and_place(
self.keys_from_next,
next_td,
out,
_allow_absent_keys=self._allow_absent_keys,
)
return out
else:
out = next_td.empty()
total_key = ()
if self.keep_other:
for key in tensordict.keys():
if key != "next":
_set(tensordict, out, key, total_key, self.excluded)
elif not self.exclude_action:
for action_key in self.action_keys:
_set_single_key(tensordict, out, action_key)
for key in next_td.keys():
_set(next_td, out, key, total_key, self.excluded)
return out
[docs]def step_mdp(
tensordict: TensorDictBase,
next_tensordict: TensorDictBase = None,
keep_other: bool = True,
exclude_reward: bool = True,
exclude_done: bool = False,
exclude_action: bool = True,
reward_keys: Union[NestedKey, List[NestedKey]] = "reward",
done_keys: Union[NestedKey, List[NestedKey]] = "done",
action_keys: Union[NestedKey, List[NestedKey]] = "action",
) -> TensorDictBase:
"""Creates a new tensordict that reflects a step in time of the input tensordict.
Given a tensordict retrieved after a step, returns the :obj:`"next"` indexed-tensordict.
The arguments allow for a precise control over what should be kept and what
should be copied from the ``"next"`` entry. The default behaviour is:
move the observation entries, reward and done states to the root, exclude
the current action and keep all extra keys (non-action, non-done, non-reward).
Args:
tensordict (TensorDictBase): tensordict with keys to be renamed
next_tensordict (TensorDictBase, optional): destination tensordict
keep_other (bool, optional): if ``True``, all keys that do not start with :obj:`'next_'` will be kept.
Default is ``True``.
exclude_reward (bool, optional): if ``True``, the :obj:`"reward"` key will be discarded
from the resulting tensordict. If ``False``, it will be copied (and replaced)
from the ``"next"`` entry (if present).
Default is ``True``.
exclude_done (bool, optional): if ``True``, the :obj:`"done"` key will be discarded
from the resulting tensordict. If ``False``, it will be copied (and replaced)
from the ``"next"`` entry (if present).
Default is ``False``.
exclude_action (bool, optional): if ``True``, the :obj:`"action"` key will
be discarded from the resulting tensordict. If ``False``, it will
be kept in the root tensordict (since it should not be present in
the ``"next"`` entry).
Default is ``True``.
reward_keys (NestedKey or list of NestedKey, optional): the keys where the reward is written. Defaults
to "reward".
done_keys (NestedKey or list of NestedKey, optional): the keys where the done is written. Defaults
to "done".
action_keys (NestedKey or list of NestedKey, optional): the keys where the action is written. Defaults
to "action".
Returns:
A new tensordict (or next_tensordict) containing the tensors of the t+1 step.
Examples:
This funtion allows for this kind of loop to be used:
>>> from tensordict import TensorDict
>>> import torch
>>> td = TensorDict({
... "done": torch.zeros((), dtype=torch.bool),
... "reward": torch.zeros(()),
... "extra": torch.zeros(()),
... "next": TensorDict({
... "done": torch.zeros((), dtype=torch.bool),
... "reward": torch.zeros(()),
... "obs": torch.zeros(()),
... }, []),
... "obs": torch.zeros(()),
... "action": torch.zeros(()),
... }, [])
>>> print(step_mdp(td))
TensorDict(
fields={
done: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.bool, is_shared=False),
extra: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.float32, is_shared=False),
obs: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.float32, is_shared=False)},
batch_size=torch.Size([]),
device=None,
is_shared=False)
>>> print(step_mdp(td, exclude_done=True)) # "done" is dropped
TensorDict(
fields={
extra: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.float32, is_shared=False),
obs: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.float32, is_shared=False)},
batch_size=torch.Size([]),
device=None,
is_shared=False)
>>> print(step_mdp(td, exclude_reward=False)) # "reward" is kept
TensorDict(
fields={
done: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.bool, is_shared=False),
extra: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.float32, is_shared=False),
obs: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.float32, is_shared=False),
reward: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.float32, is_shared=False)},
batch_size=torch.Size([]),
device=None,
is_shared=False)
>>> print(step_mdp(td, exclude_action=False)) # "action" persists at the root
TensorDict(
fields={
action: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.float32, is_shared=False),
done: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.bool, is_shared=False),
extra: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.float32, is_shared=False),
obs: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.float32, is_shared=False)},
batch_size=torch.Size([]),
device=None,
is_shared=False)
>>> print(step_mdp(td, keep_other=False)) # "extra" is missing
TensorDict(
fields={
done: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.bool, is_shared=False),
obs: Tensor(shape=torch.Size([]), device=cpu, dtype=torch.float32, is_shared=False)},
batch_size=torch.Size([]),
device=None,
is_shared=False)
.. warning:: This function will not work properly if the reward key is also part of the input key when
the reward keys are excluded. This is why the :class:`~torchrl.envs.RewardSum` transform registers
the episode reward in the observation and not the reward spec by default.
When using the fast, cached version of this function (``_StepMDP``), this issue should not
be observed.
"""
if isinstance(tensordict, LazyStackedTensorDict):
if next_tensordict is not None:
next_tensordicts = next_tensordict.unbind(tensordict.stack_dim)
else:
next_tensordicts = [None] * len(tensordict.tensordicts)
out = LazyStackedTensorDict.lazy_stack(
[
step_mdp(
td,
next_tensordict=ntd,
keep_other=keep_other,
exclude_reward=exclude_reward,
exclude_done=exclude_done,
exclude_action=exclude_action,
reward_keys=reward_keys,
done_keys=done_keys,
action_keys=action_keys,
)
for td, ntd in zip(tensordict.tensordicts, next_tensordicts)
],
tensordict.stack_dim,
)
if next_tensordict is not None:
next_tensordict.update(out)
return next_tensordict
return out
if not isinstance(action_keys, list):
action_keys = [action_keys]
if not isinstance(done_keys, list):
done_keys = [done_keys]
if not isinstance(reward_keys, list):
reward_keys = [reward_keys]
excluded = set()
if exclude_reward:
excluded = excluded.union(reward_keys)
if exclude_done:
excluded = excluded.union(done_keys)
if exclude_action:
excluded = excluded.union(action_keys)
next_td = tensordict.get("next")
out = next_td.empty()
total_key = ()
if keep_other:
for key in tensordict.keys():
if key != "next":
_set(tensordict, out, key, total_key, excluded)
elif not exclude_action:
for action_key in action_keys:
_set_single_key(tensordict, out, action_key)
for key in next_td.keys():
_set(next_td, out, key, total_key, excluded)
if next_tensordict is not None:
return next_tensordict.update(out)
else:
return out
def _set_single_key(
source: TensorDictBase,
dest: TensorDictBase,
key: str | tuple,
clone: bool = False,
device=None,
):
# key should be already unraveled
if isinstance(key, str):
key = (key,)
for k in key:
try:
val = source._get_str(k, None)
if is_tensor_collection(val):
new_val = dest._get_str(k, None)
if new_val is None:
new_val = val.empty()
dest._set_str(
k, new_val, inplace=False, validated=True, non_blocking=False
)
source = val
dest = new_val
else:
if device is not None and val.device != device:
val = val.to(device, non_blocking=True)
elif clone:
val = val.clone()
dest._set_str(k, val, inplace=False, validated=True, non_blocking=False)
# This is a temporary solution to understand if a key is heterogeneous
# while not having performance impact when the exception is not raised
except RuntimeError as err:
if re.match(r"Found more than one unique shape in the tensors", str(err)):
# this is a het key
for s_td, d_td in zip(source.tensordicts, dest.tensordicts):
_set_single_key(s_td, d_td, k, clone=clone, device=device)
break
else:
raise err
def _set(source, dest, key, total_key, excluded):
total_key = total_key + (key,)
non_empty = False
if unravel_key(total_key) not in excluded:
try:
val = source.get(key)
if is_tensor_collection(val):
# if val is a tensordict we need to copy the structure
new_val = dest.get(key, None)
if new_val is None:
new_val = val.empty()
non_empty_local = False
for subkey in val.keys():
non_empty_local = (
_set(val, new_val, subkey, total_key, excluded)
or non_empty_local
)
if non_empty_local:
# dest.set(key, new_val)
dest._set_str(
key, new_val, inplace=False, validated=True, non_blocking=False
)
non_empty = non_empty_local
else:
non_empty = True
# dest.set(key, val)
dest._set_str(
key, val, inplace=False, validated=True, non_blocking=False
)
# This is a temporary solution to understand if a key is heterogeneous
# while not having performance impact when the exception is not raised
except RuntimeError as err:
if re.match(r"Found more than one unique shape in the tensors", str(err)):
# this is a het key
non_empty_local = False
for s_td, d_td in zip(source.tensordicts, dest.tensordicts):
non_empty_local = (
_set(s_td, d_td, key, total_key, excluded) or non_empty_local
)
non_empty = non_empty_local
else:
raise err
return non_empty
[docs]def get_available_libraries():
"""Returns all the supported libraries."""
return SUPPORTED_LIBRARIES
def _check_gym():
"""Returns True if the gym library is installed."""
return importlib.util.find_spec("gym") is not None
def _check_gym_atari():
"""Returns True if the gym library is installed and atari envs can be found."""
if not _check_gym():
return False
return importlib.util.find_spec("atari-py") is not None
def _check_mario():
"""Returns True if the "gym-super-mario-bros" library is installed."""
return importlib.util.find_spec("gym-super-mario-bros") is not None
def _check_dmcontrol():
"""Returns True if the "dm-control" library is installed."""
return importlib.util.find_spec("dm_control") is not None
def _check_dmlab():
"""Returns True if the "deepmind-lab" library is installed."""
return importlib.util.find_spec("deepmind_lab") is not None
SUPPORTED_LIBRARIES = {
"gym": _check_gym(), # OpenAI
"gym[atari]": _check_gym_atari(), #
"dm_control": _check_dmcontrol(),
"habitat": None,
"gym-super-mario-bros": _check_mario(),
# "vizdoom": None, # gym based, https://github.com/mwydmuch/ViZDoom
# "openspiel": None, # DM, https://github.com/deepmind/open_spiel
# "pysc2": None, # DM, https://github.com/deepmind/pysc2
# "deepmind_lab": _check_dmlab(),
# DM, https://github.com/deepmind/lab, https://github.com/deepmind/lab/tree/master/python/pip_package
# "serpent.ai": None, # https://github.com/SerpentAI/SerpentAI
# "gfootball": None, # 2.8k G, https://github.com/google-research/football
# DM, https://github.com/deepmind/dm_control
# FB, https://github.com/facebookresearch/habitat-sim
# "meta-world": None, # https://github.com/rlworkgroup/metaworld
# "minerl": None, # https://github.com/minerllabs/minerl
# "multi-agent-emergence-environments": None,
# OpenAI, https://github.com/openai/multi-agent-emergence-environments
# "procgen": None, # OpenAI, https://github.com/openai/procgen
# "pybullet": None, # https://github.com/benelot/pybullet-gym
# "realworld_rl_suite": None,
# G, https://github.com/google-research/realworldrl_suite
# "rlcard": None, # https://github.com/datamllab/rlcard
# "screeps": None, # https://github.com/screeps/screeps
# "ml-agents": None,
}
def _per_level_env_check(data0, data1, check_dtype):
"""Checks shape and dtype of two tensordicts, accounting for lazy stacks."""
if isinstance(data0, LazyStackedTensorDict) and isinstance(
data1, LazyStackedTensorDict
):
if data0.stack_dim != data1.stack_dim:
raise AssertionError(f"Stack dimension mismatch: {data0} vs {data1}.")
for _data0, _data1 in zip(data0.tensordicts, data1.tensordicts):
_per_level_env_check(_data0, _data1, check_dtype=check_dtype)
return
else:
keys0 = set(data0.keys())
keys1 = set(data1.keys())
if keys0 != keys1:
raise AssertionError(f"Keys mismatch: {keys0} vs {keys1}")
for key in keys0:
_data0 = data0[key]
_data1 = data1[key]
if _data0.shape != _data1.shape:
raise AssertionError(
f"The shapes of the real and fake tensordict don't match for key {key}. "
f"Got fake={_data0.shape} and real={_data1.shape}."
)
if isinstance(_data0, TensorDictBase):
_per_level_env_check(_data0, _data1, check_dtype=check_dtype)
else:
if check_dtype and (_data0.dtype != _data1.dtype):
raise AssertionError(
f"The dtypes of the real and fake tensordict don't match for key {key}. "
f"Got fake={_data0.dtype} and real={_data1.dtype}."
)
[docs]def check_env_specs(
env, return_contiguous=True, check_dtype=True, seed: int | None = None
):
"""Tests an environment specs against the results of short rollout.
This test function should be used as a sanity check for an env wrapped with
torchrl's EnvBase subclasses: any discrepancy between the expected data and
the data collected should raise an assertion error.
A broken environment spec will likely make it impossible to use parallel
environments.
Args:
env (EnvBase): the env for which the specs have to be checked against data.
return_contiguous (bool, optional): if ``True``, the random rollout will be called with
return_contiguous=True. This will fail in some cases (e.g. heterogeneous shapes
of inputs/outputs). Defaults to True.
check_dtype (bool, optional): if False, dtype checks will be skipped.
Defaults to True.
seed (int, optional): for reproducibility, a seed can be set.
The seed will be set in pytorch temporarily, then the RNG state will
be reverted to what it was before. For the env, we set the seed but since
setting the rng state back to what is was isn't a feature of most environment,
we leave it to the user to accomplish that.
Defaults to ``None``.
Caution: this function resets the env seed. It should be used "offline" to
check that an env is adequately constructed, but it may affect the seeding
of an experiment and as such should be kept out of training scripts.
"""
if seed is not None:
device = (
env.device if env.device is not None and env.device.type == "cuda" else None
)
with _rng_decorator(seed, device=device):
env.set_seed(seed)
return check_env_specs(
env, return_contiguous=return_contiguous, check_dtype=check_dtype
)
fake_tensordict = env.fake_tensordict()
real_tensordict = env.rollout(3, return_contiguous=return_contiguous)
if return_contiguous:
fake_tensordict = fake_tensordict.unsqueeze(real_tensordict.batch_dims - 1)
fake_tensordict = fake_tensordict.expand(*real_tensordict.shape)
else:
fake_tensordict = LazyStackedTensorDict.lazy_stack(
[fake_tensordict.clone() for _ in range(3)], -1
)
# eliminate empty containers
fake_tensordict_select = fake_tensordict.select(*fake_tensordict.keys(True, True))
real_tensordict_select = real_tensordict.select(*real_tensordict.keys(True, True))
# check keys
fake_tensordict_keys = set(fake_tensordict.keys(True, True))
real_tensordict_keys = set(real_tensordict.keys(True, True))
if fake_tensordict_keys != real_tensordict_keys:
raise AssertionError(
f"""The keys of the specs and data do not match:
- List of keys present in real but not in fake: {real_tensordict_keys-fake_tensordict_keys},
- List of keys present in fake but not in real: {fake_tensordict_keys-real_tensordict_keys}.
"""
)
if (
fake_tensordict_select.apply(lambda x: torch.zeros_like(x))
!= real_tensordict_select.apply(lambda x: torch.zeros_like(x))
).any():
raise AssertionError(
"zeroing the two tensordicts did not make them identical. "
f"Check for discrepancies:\nFake=\n{fake_tensordict}\nReal=\n{real_tensordict}"
)
# Checks shapes and eventually dtypes of keys at all nesting levels
_per_level_env_check(
fake_tensordict_select, real_tensordict_select, check_dtype=check_dtype
)
# Check specs
last_td = real_tensordict[..., -1]
last_td = env.rand_action(last_td)
full_action_spec = env.input_spec["full_action_spec"]
full_state_spec = env.input_spec["full_state_spec"]
full_observation_spec = env.output_spec["full_observation_spec"]
full_reward_spec = env.output_spec["full_reward_spec"]
full_done_spec = env.output_spec["full_done_spec"]
for name, spec in (
("action", full_action_spec),
("state", full_state_spec),
("done", full_done_spec),
("obs", full_observation_spec),
):
if not check_no_exclusive_keys(spec):
raise AssertionError(
"It appears you are using some LazyStackedCompositeSpecs with exclusive keys "
"(keys present in some but not all of the stacked specs). To use such heterogeneous specs, "
"you will need to first pass your stack through `torchrl.data.consolidate_spec`."
)
if spec is None:
spec = CompositeSpec(shape=env.batch_size, device=env.device)
td = last_td.select(*spec.keys(True, True), strict=True)
if not spec.is_in(td):
raise AssertionError(
f"spec check failed at root for spec {name}={spec} and data {td}."
)
for name, spec in (
("reward", full_reward_spec),
("done", full_done_spec),
("obs", full_observation_spec),
):
if spec is None:
spec = CompositeSpec(shape=env.batch_size, device=env.device)
td = last_td.get("next").select(*spec.keys(True, True), strict=True)
if not spec.is_in(td):
raise AssertionError(
f"spec check failed at root for spec {name}={spec} and data {td}."
)
torchrl_logger.info("check_env_specs succeeded!")
def _selective_unsqueeze(tensor: torch.Tensor, batch_size: torch.Size, dim: int = -1):
shape_len = len(tensor.shape)
if shape_len < len(batch_size):
raise RuntimeError(
f"Tensor has less dims than batch_size. shape:{tensor.shape}, batch_size: {batch_size}"
)
if tensor.shape[: len(batch_size)] != batch_size:
raise RuntimeError(
f"Tensor does not have given batch_size. shape:{tensor.shape}, batch_size: {batch_size}"
)
if shape_len == len(batch_size):
return tensor.unsqueeze(dim=dim)
return tensor
def _sort_keys(element):
if isinstance(element, tuple):
element = unravel_key(element)
return "_-|-_".join(element)
return element
[docs]def make_composite_from_td(data):
"""Creates a CompositeSpec instance from a tensordict, assuming all values are unbounded.
Args:
data (tensordict.TensorDict): a tensordict to be mapped onto a CompositeSpec.
Examples:
>>> from tensordict import TensorDict
>>> data = TensorDict({
... "obs": torch.randn(3),
... "action": torch.zeros(2, dtype=torch.int),
... "next": {"obs": torch.randn(3), "reward": torch.randn(1)}
... }, [])
>>> spec = make_composite_from_td(data)
>>> print(spec)
CompositeSpec(
obs: UnboundedContinuousTensorSpec(
shape=torch.Size([3]), space=None, device=cpu, dtype=torch.float32, domain=continuous),
action: UnboundedContinuousTensorSpec(
shape=torch.Size([2]), space=None, device=cpu, dtype=torch.int32, domain=continuous),
next: CompositeSpec(
obs: UnboundedContinuousTensorSpec(
shape=torch.Size([3]), space=None, device=cpu, dtype=torch.float32, domain=continuous),
reward: UnboundedContinuousTensorSpec(
shape=torch.Size([1]), space=ContinuousBox(low=Tensor(shape=torch.Size([]), device=cpu, dtype=torch.float32, contiguous=True), high=Tensor(shape=torch.Size([]), device=cpu, dtype=torch.float32, contiguous=True)), device=cpu, dtype=torch.float32, domain=continuous), device=cpu, shape=torch.Size([])), device=cpu, shape=torch.Size([]))
>>> assert (spec.zero() == data.zero_()).all()
"""
# custom funtion to convert a tensordict in a similar spec structure
# of unbounded values.
composite = CompositeSpec(
{
key: make_composite_from_td(tensor)
if isinstance(tensor, TensorDictBase)
else UnboundedContinuousTensorSpec(
dtype=tensor.dtype,
device=tensor.device,
shape=tensor.shape if tensor.shape else [1],
)
for key, tensor in data.items()
},
shape=data.shape,
)
return composite
@contextlib.contextmanager
def clear_mpi_env_vars():
"""Clears the MPI of environment variables.
`from mpi4py import MPI` will call `MPI_Init` by default.
If the child process has MPI environment variables, MPI will think that the child process
is an MPI process just like the parent and do bad things such as hang.
This context manager is a hacky way to clear those environment variables
temporarily such as when we are starting multiprocessing Processes.
Yields:
Yields for the context manager
"""
removed_environment = {}
for k, v in list(os.environ.items()):
for prefix in ["OMPI_", "PMI_"]:
if k.startswith(prefix):
removed_environment[k] = v
del os.environ[k]
try:
yield
finally:
os.environ.update(removed_environment)
[docs]class MarlGroupMapType(Enum):
"""Marl Group Map Type.
As a feature of torchrl multiagent, you are able to control the grouping of agents in your environment.
You can group agents together (stacking their tensors) to leverage vectorization when passing them through the same
neural network. You can split agents in different groups where they are heterogenous or should be processed by
different neural networks. To group, you just need to pass a ``group_map`` at env constructiuon time.
Otherwise, you can choose one of the premade grouping strategies from this class.
- With ``group_map=MarlGroupMapType.ALL_IN_ONE_GROUP`` and
agents ``["agent_0", "agent_1", "agent_2", "agent_3"]``,
the tensordicts coming and going from your environment will look
something like:
>>> print(env.rand_action(env.reset()))
TensorDict(
fields={
agents: TensorDict(
fields={
action: Tensor(shape=torch.Size([4, 9]), device=cpu, dtype=torch.int64, is_shared=False),
done: Tensor(shape=torch.Size([4, 1]), device=cpu, dtype=torch.bool, is_shared=False),
observation: Tensor(shape=torch.Size([4, 3, 3, 2]), device=cpu, dtype=torch.int8, is_shared=False)},
batch_size=torch.Size([4]))},
batch_size=torch.Size([]))
>>> print(env.group_map)
{"agents": ["agent_0", "agent_1", "agent_2", "agent_3]}
- With ``group_map=MarlGroupMapType.ONE_GROUP_PER_AGENT`` and
agents ``["agent_0", "agent_1", "agent_2", "agent_3"]``,
the tensordicts coming and going from your environment will look
something like:
>>> print(env.rand_action(env.reset()))
TensorDict(
fields={
agent_0: TensorDict(
fields={
action: Tensor(shape=torch.Size([9]), device=cpu, dtype=torch.int64, is_shared=False),
done: Tensor(shape=torch.Size([1]), device=cpu, dtype=torch.bool, is_shared=False),
observation: Tensor(shape=torch.Size([3, 3, 2]), device=cpu, dtype=torch.int8, is_shared=False)},
batch_size=torch.Size([]))},
agent_1: TensorDict(
fields={
action: Tensor(shape=torch.Size([9]), device=cpu, dtype=torch.int64, is_shared=False),
done: Tensor(shape=torch.Size([1]), device=cpu, dtype=torch.bool, is_shared=False),
observation: Tensor(shape=torch.Size([3, 3, 2]), device=cpu, dtype=torch.int8, is_shared=False)},
batch_size=torch.Size([]))},
agent_2: TensorDict(
fields={
action: Tensor(shape=torch.Size([9]), device=cpu, dtype=torch.int64, is_shared=False),
done: Tensor(shape=torch.Size([1]), device=cpu, dtype=torch.bool, is_shared=False),
observation: Tensor(shape=torch.Size([3, 3, 2]), device=cpu, dtype=torch.int8, is_shared=False)},
batch_size=torch.Size([]))},
agent_3: TensorDict(
fields={
action: Tensor(shape=torch.Size([9]), device=cpu, dtype=torch.int64, is_shared=False),
done: Tensor(shape=torch.Size([1]), device=cpu, dtype=torch.bool, is_shared=False),
observation: Tensor(shape=torch.Size([3, 3, 2]), device=cpu, dtype=torch.int8, is_shared=False)},
batch_size=torch.Size([]))},
batch_size=torch.Size([]))
>>> print(env.group_map)
{"agent_0": ["agent_0"], "agent_1": ["agent_1"], "agent_2": ["agent_2"], "agent_3": ["agent_3"]}
"""
ALL_IN_ONE_GROUP = 1
ONE_GROUP_PER_AGENT = 2
def get_group_map(self, agent_names: List[str]):
if self == MarlGroupMapType.ALL_IN_ONE_GROUP:
return {"agents": agent_names}
elif self == MarlGroupMapType.ONE_GROUP_PER_AGENT:
return {agent_name: [agent_name] for agent_name in agent_names}
[docs]def check_marl_grouping(group_map: Dict[str, List[str]], agent_names: List[str]):
"""Check MARL group map.
Performs checks on the group map of a marl environment to assess its validity.
Raises an error in cas of an invalid group_map.
Args:
group_map (Dict[str, List[str]]): the group map mapping group names to list of agent names in the group
agent_names (List[str]): a list of all the agent names in the environment4
Examples:
>>> from torchrl.envs.utils import MarlGroupMapType, check_marl_grouping
>>> agent_names = ["agent_0", "agent_1", "agent_2"]
>>> check_marl_grouping(MarlGroupMapType.ALL_IN_ONE_GROUP.get_group_map(agent_names), agent_names)
"""
n_agents = len(agent_names)
if n_agents == 0:
raise ValueError("No agents passed")
if len(set(agent_names)) != n_agents:
raise ValueError("There are agents with the same name")
if len(group_map.keys()) > n_agents:
raise ValueError(
f"Number of groups {len(group_map.keys())} greater than number of agents {n_agents}"
)
found_agents = {agent_name: False for agent_name in agent_names}
for group_name, group in group_map.items():
if not len(group):
raise ValueError(f"Group {group_name} is empty")
for agent_name in group:
if agent_name not in found_agents:
raise ValueError(f"Agent {agent_name} not present in environment")
if not found_agents[agent_name]:
found_agents[agent_name] = True
else:
raise ValueError(f"Agent {agent_name} present more than once")
for agent_name, found in found_agents.items():
if not found:
raise ValueError(f"Agent {agent_name} not found in any group")
def _terminated_or_truncated(
data: TensorDictBase,
full_done_spec: TensorSpec | None = None,
key: str | None = "_reset",
write_full_false: bool = False,
) -> bool:
"""Reads the done / terminated / truncated keys within a tensordict, and writes a new tensor where the values of both signals are aggregated.
The modification occurs in-place within the TensorDict instance provided.
This function can be used to compute the `"_reset"` signals in batched
or multiagent settings, hence the default name of the output key.
Args:
data (TensorDictBase): the input data, generally resulting from a call
to :meth:`~torchrl.envs.EnvBase.step`.
full_done_spec (TensorSpec, optional): the done_spec from the env,
indicating where the done leaves have to be found.
If not provided, the default
``"done"``, ``"terminated"`` and ``"truncated"`` entries will be
searched for in the data.
key (NestedKey, optional): where the aggregated result should be written.
If ``None``, then the function will not write any key but just output
whether any of the done values was true.
.. note:: if a value is already present for the ``key`` entry,
the previous value will prevail and no update will be achieved.
write_full_false (bool, optional): if ``True``, the reset keys will be
written even if the output is ``False`` (ie, no done is ``True``
in the provided data structure).
Defaults to ``False``.
Returns: a boolean value indicating whether any of the done states found in the data
contained a ``True``.
Examples:
>>> from torchrl.data.tensor_specs import DiscreteTensorSpec
>>> from tensordict import TensorDict
>>> spec = CompositeSpec(
... done=DiscreteTensorSpec(2, dtype=torch.bool),
... truncated=DiscreteTensorSpec(2, dtype=torch.bool),
... nested=CompositeSpec(
... done=DiscreteTensorSpec(2, dtype=torch.bool),
... truncated=DiscreteTensorSpec(2, dtype=torch.bool),
... )
... )
>>> data = TensorDict({
... "done": True, "truncated": False,
... "nested": {"done": False, "truncated": True}},
... batch_size=[]
... )
>>> data = _terminated_or_truncated(data, spec)
>>> print(data["_reset"])
tensor(True)
>>> print(data["nested", "_reset"])
tensor(True)
"""
list_of_keys = []
def inner_terminated_or_truncated(data, full_done_spec, key, curr_done_key=()):
any_eot = False
aggregate = None
if full_done_spec is None:
tds = {}
found_leaf = 0
for eot_key, item in data.items():
if eot_key in ("terminated", "truncated", "done"):
done = item
if aggregate is None:
aggregate = False
aggregate = aggregate | done
found_leaf += 1
elif isinstance(item, TensorDictBase):
tds[eot_key] = item
# The done signals in a root td prevail over done in the leaves
if tds:
for eot_key, item in tds.items():
any_eot_td = inner_terminated_or_truncated(
data=item,
full_done_spec=None,
key=key,
curr_done_key=curr_done_key + (eot_key,),
)
if not found_leaf:
any_eot = any_eot | any_eot_td
else:
composite_spec = {}
found_leaf = 0
for eot_key, item in full_done_spec.items():
if isinstance(item, CompositeSpec):
composite_spec[eot_key] = item
else:
found_leaf += 1
stop = data.get(eot_key, None)
if stop is None:
stop = torch.zeros(
(*data.shape, 1), dtype=torch.bool, device=data.device
)
if aggregate is None:
aggregate = False
aggregate = aggregate | stop
# The done signals in a root td prevail over done in the leaves
if composite_spec:
for eot_key, item in composite_spec.items():
any_eot_td = inner_terminated_or_truncated(
data=data.get(eot_key),
full_done_spec=item,
key=key,
curr_done_key=curr_done_key + (eot_key,),
)
if not found_leaf:
any_eot = any_eot_td | any_eot
if aggregate is not None:
if key is not None:
if aggregate.ndim > data.ndim:
# accounts for trailing singleton dim in done.
# _reset is always expanded on the right if needed so this can only be useful
aggregate = aggregate.squeeze(-1)
data.set(key, aggregate)
list_of_keys.append(curr_done_key + (key,))
any_eot = any_eot | aggregate.any()
return any_eot
any_eot = inner_terminated_or_truncated(data, full_done_spec, key)
if not any_eot and not write_full_false:
# remove the list of reset keys
data.exclude(*list_of_keys, inplace=True)
return any_eot
[docs]def terminated_or_truncated(
data: TensorDictBase,
full_done_spec: TensorSpec | None = None,
key: str = "_reset",
write_full_false: bool = False,
) -> bool:
"""Reads the done / terminated / truncated keys within a tensordict, and writes a new tensor where the values of both signals are aggregated.
The modification occurs in-place within the TensorDict instance provided.
This function can be used to compute the `"_reset"` signals in batched
or multiagent settings, hence the default name of the output key.
Args:
data (TensorDictBase): the input data, generally resulting from a call
to :meth:`~torchrl.envs.EnvBase.step`.
full_done_spec (TensorSpec, optional): the done_spec from the env,
indicating where the done leaves have to be found.
If not provided, the default
``"done"``, ``"terminated"`` and ``"truncated"`` entries will be
searched for in the data.
key (NestedKey, optional): where the aggregated result should be written.
If ``None``, then the function will not write any key but just output
whether any of the done values was true.
.. note:: if a value is already present for the ``key`` entry,
the previous value will prevail and no update will be achieved.
write_full_false (bool, optional): if ``True``, the reset keys will be
written even if the output is ``False`` (ie, no done is ``True``
in the provided data structure).
Defaults to ``False``.
Returns: a boolean value indicating whether any of the done states found in the data
contained a ``True``.
Examples:
>>> from torchrl.data.tensor_specs import DiscreteTensorSpec
>>> from tensordict import TensorDict
>>> spec = CompositeSpec(
... done=DiscreteTensorSpec(2, dtype=torch.bool),
... truncated=DiscreteTensorSpec(2, dtype=torch.bool),
... nested=CompositeSpec(
... done=DiscreteTensorSpec(2, dtype=torch.bool),
... truncated=DiscreteTensorSpec(2, dtype=torch.bool),
... )
... )
>>> data = TensorDict({
... "done": True, "truncated": False,
... "nested": {"done": False, "truncated": True}},
... batch_size=[]
... )
>>> data = _terminated_or_truncated(data, spec)
>>> print(data["_reset"])
tensor(True)
>>> print(data["nested", "_reset"])
tensor(True)
"""
list_of_keys = []
def inner_terminated_or_truncated(data, full_done_spec, key, curr_done_key=()):
any_eot = False
aggregate = None
if full_done_spec is None:
for eot_key, item in data.items():
if eot_key == "done":
done = data.get(eot_key, None)
if done is None:
done = torch.zeros(
(*data.shape, 1), dtype=torch.bool, device=data.device
)
if aggregate is None:
aggregate = torch.tensor(False, device=done.device)
aggregate = aggregate | done
elif eot_key in ("terminated", "truncated"):
done = data.get(eot_key, None)
if done is None:
done = torch.zeros(
(*data.shape, 1), dtype=torch.bool, device=data.device
)
if aggregate is None:
aggregate = torch.tensor(False, device=done.device)
aggregate = aggregate | done
elif isinstance(item, TensorDictBase):
any_eot = any_eot | inner_terminated_or_truncated(
data=item,
full_done_spec=None,
key=key,
curr_done_key=curr_done_key + (eot_key,),
)
else:
for eot_key, item in full_done_spec.items():
if isinstance(item, CompositeSpec):
any_eot = any_eot | inner_terminated_or_truncated(
data=data.get(eot_key),
full_done_spec=item,
key=key,
curr_done_key=curr_done_key + (eot_key,),
)
else:
sop = data.get(eot_key, None)
if sop is None:
sop = torch.zeros(
(*data.shape, 1), dtype=torch.bool, device=data.device
)
if aggregate is None:
aggregate = torch.tensor(False, device=sop.device)
aggregate = aggregate | sop
if aggregate is not None:
if key is not None:
data.set(key, aggregate)
list_of_keys.append(curr_done_key + (key,))
any_eot = any_eot | aggregate.any()
return any_eot
any_eot = inner_terminated_or_truncated(data, full_done_spec, key)
if not any_eot and not write_full_false:
# remove the list of reset keys
data.exclude(*list_of_keys, inplace=True)
return any_eot
PARTIAL_MISSING_ERR = "Some reset keys were present but not all. Either all the `'_reset'` entries must be present, or none."
def _aggregate_end_of_traj(
data: TensorDictBase, reset_keys=None, done_keys=None
) -> torch.Tensor:
# goes through the tensordict and brings the _reset information to
# a boolean tensor of the shape of the tensordict.
batch_size = data.batch_size
n = len(batch_size)
if done_keys is not None and reset_keys is None:
reset_keys = {_replace_last(key, "done") for key in done_keys}
if reset_keys is not None:
reset = False
has_missing = None
for key in reset_keys:
local_reset = data.get(key, None)
if local_reset is None:
if has_missing is False:
raise ValueError(PARTIAL_MISSING_ERR)
has_missing = True
continue
elif has_missing:
raise ValueError(PARTIAL_MISSING_ERR)
has_missing = False
if local_reset.ndim > n:
local_reset = local_reset.flatten(n, local_reset.ndim - 1)
local_reset = local_reset.any(-1)
reset = reset | local_reset
if has_missing:
return torch.ones(batch_size, dtype=torch.bool, device=data.device)
return reset
reset = torch.tensor(False, device=data.device)
def skim_through(td, reset=reset):
for key in td.keys():
if key == "_reset":
local_reset = td.get(key)
if local_reset.ndim > n:
local_reset = local_reset.flatten(n, local_reset.ndim - 1)
local_reset = local_reset.any(-1)
reset = reset | local_reset
# we need to check the entry class without getting the value,
# because some lazy tensordicts may prevent calls to items().
# This introduces some slight overhead as when we encounter a
# tensordict item, we'll need to get it twice.
elif is_tensor_collection(td.entry_class(key)):
value = td.get(key)
reset = skim_through(value, reset=reset)
return reset
reset = skim_through(data)
return reset
def _update_during_reset(
tensordict_reset: TensorDictBase,
tensordict: TensorDictBase,
reset_keys: List[NestedKey],
):
"""Updates the input tensordict with the reset data, based on the reset keys."""
roots = set()
for reset_key in reset_keys:
# get the node of the reset key
if isinstance(reset_key, tuple):
# the reset key *must* have gone through unravel_key
# we don't test it to avoid induced overhead
node_key = reset_key[:-1]
node_reset = tensordict_reset.get(node_key)
node = tensordict.get(node_key)
reset_key_tuple = reset_key
else:
node_reset = tensordict_reset
node = tensordict
reset_key_tuple = (reset_key,)
# get the reset signal
reset = tensordict.pop(reset_key, None)
# check if this reset should be ignored -- this happens whenever the a
# root node has already been updated
root = () if isinstance(reset_key, str) else reset_key[:-1]
processed = any(reset_key_tuple[: len(x)] == x for x in roots)
roots.add(root)
if processed:
continue
if reset is None or reset.all():
# perform simple update, at a single level.
# by contract, a reset signal at one level cannot
# be followed by other resets at nested levels, so it's safe to
# simply update
node.update(node_reset)
else:
# there can be two cases: (1) the key is present in both tds,
# in which case we use the reset mask to update
# (2) the key is not present in the input tensordict, in which
# case we just return the data
# empty tensordicts won't be returned
if reset.ndim > node.ndim:
reset = reset.flatten(node.ndim, reset.ndim - 1)
reset = reset.any(-1)
reset = reset.reshape(node.shape)
# node.update(node.where(~reset, other=node_reset, pad=0))
node.where(~reset, other=node_reset, out=node, pad=0)
return tensordict
def _repr_by_depth(key):
"""Used to sort keys based on nesting level."""
key = unravel_key(key)
if isinstance(key, str):
return (0, key)
else:
return (len(key) - 1, ".".join(key))
def _make_compatible_policy(policy, observation_spec, env=None, fast_wrap=False):
if policy is None:
if env is None:
raise ValueError(
"env must be provided to _get_policy_and_device if policy is None"
)
policy = RandomPolicy(env.input_spec["full_action_spec"])
# make sure policy is an nn.Module
policy = _NonParametricPolicyWrapper(policy)
if not _policy_is_tensordict_compatible(policy):
# policy is a nn.Module that doesn't operate on tensordicts directly
# so we attempt to auto-wrap policy with TensorDictModule
if observation_spec is None:
raise ValueError(
"Unable to read observation_spec from the environment. This is "
"required to check compatibility of the environment and policy "
"since the policy is a nn.Module that operates on tensors "
"rather than a TensorDictModule or a nn.Module that accepts a "
"TensorDict as input and defines in_keys and out_keys."
)
try:
sig = policy.forward.__signature__
except AttributeError:
sig = inspect.signature(policy.forward)
# we check if all the mandatory params are there
params = list(sig.parameters.keys())
if (
set(sig.parameters) == {"tensordict"}
or set(sig.parameters) == {"td"}
or (
len(params) == 1
and is_tensor_collection(sig.parameters[params[0]].annotation)
)
):
return policy
if fast_wrap:
in_keys = list(observation_spec.keys())
out_keys = list(env.action_keys)
return TensorDictModule(policy, in_keys=in_keys, out_keys=out_keys)
required_kwargs = {
str(k) for k, p in sig.parameters.items() if p.default is inspect._empty
}
next_observation = {
key: value for key, value in observation_spec.rand().items()
}
if not required_kwargs.difference(set(next_observation)):
in_keys = [str(k) for k in sig.parameters if k in next_observation]
if env is None:
out_keys = ["action"]
else:
out_keys = list(env.action_keys)
for p in policy.parameters():
policy_device = p.device
break
else:
policy_device = None
if policy_device:
next_observation = tree_map(
lambda x: x.to(policy_device), next_observation
)
output = policy(**next_observation)
if isinstance(output, tuple):
out_keys.extend(f"output{i + 1}" for i in range(len(output) - 1))
policy = TensorDictModule(policy, in_keys=in_keys, out_keys=out_keys)
else:
raise TypeError(
f"""Arguments to policy.forward are incompatible with entries in
env.observation_spec (got incongruent signatures: fun signature is {set(sig.parameters)} vs specs {set(next_observation)}).
If you want TorchRL to automatically wrap your policy with a TensorDictModule
then the arguments to policy.forward must correspond one-to-one with entries
in env.observation_spec.
For more complex behaviour and more control you can consider writing your
own TensorDictModule.
Check the collector documentation to know more about accepted policies.
"""
)
return policy
def _policy_is_tensordict_compatible(policy: nn.Module):
if isinstance(policy, _NonParametricPolicyWrapper) and isinstance(
policy.policy, RandomPolicy
):
return True
if isinstance(policy, TensorDictModuleBase):
return True
sig = inspect.signature(policy.forward)
if (
len(sig.parameters) == 1
and hasattr(policy, "in_keys")
and hasattr(policy, "out_keys")
):
raise RuntimeError(
"Passing a policy that is not a tensordict.nn.TensorDictModuleBase subclass but has in_keys and out_keys "
"is deprecated. Users should inherit from this class (which "
"has very few restrictions) to make the experience smoother. "
"Simply change your policy from `class Policy(nn.Module)` to `Policy(tensordict.nn.TensorDictModuleBase)` "
"and this error should disappear.",
)
elif not hasattr(policy, "in_keys") and not hasattr(policy, "out_keys"):
# if it's not a TensorDictModule, and in_keys and out_keys are not defined then
# we assume no TensorDict compatibility and will try to wrap it.
return False
# if in_keys or out_keys were defined but policy is not a TensorDictModule or
# accepts multiple arguments then it's likely the user is trying to do something
# that will have undetermined behaviour, we raise an error
raise TypeError(
"Received a policy that defines in_keys or out_keys and also expects multiple "
"arguments to policy.forward. If the policy is compatible with TensorDict, it "
"should take a single argument of type TensorDict to policy.forward and define "
"both in_keys and out_keys. Alternatively, policy.forward can accept "
"arbitrarily many tensor inputs and leave in_keys and out_keys undefined and "
"TorchRL will attempt to automatically wrap the policy with a TensorDictModule."
)
[docs]class RandomPolicy:
"""A random policy for data collectors.
This is a wrapper around the action_spec.rand method.
Args:
action_spec: TensorSpec object describing the action specs
Examples:
>>> from tensordict import TensorDict
>>> from torchrl.data.tensor_specs import BoundedTensorSpec
>>> action_spec = BoundedTensorSpec(-torch.ones(3), torch.ones(3))
>>> actor = RandomPolicy(action_spec=action_spec)
>>> td = actor(TensorDict({}, batch_size=[])) # selects a random action in the cube [-1; 1]
"""
def __init__(self, action_spec: TensorSpec, action_key: NestedKey = "action"):
super().__init__()
self.action_spec = action_spec.clone()
self.action_key = action_key
def __call__(self, td: TensorDictBase) -> TensorDictBase:
if isinstance(self.action_spec, CompositeSpec):
return td.update(self.action_spec.rand())
else:
return td.set(self.action_key, self.action_spec.rand())
class _PolicyMetaClass(abc.ABCMeta):
def __call__(cls, *args, **kwargs):
# no kwargs
if isinstance(args[0], nn.Module):
return args[0]
return super().__call__(*args)
class _NonParametricPolicyWrapper(nn.Module, metaclass=_PolicyMetaClass):
"""A wrapper for non-parametric policies."""
def __init__(self, policy):
super().__init__()
self.policy = policy
@property
def forward(self):
forward = self.__dict__.get("_forward", None)
if forward is None:
@functools.wraps(self.policy)
def forward(*input, **kwargs):
return self.policy.__call__(*input, **kwargs)
self.__dict__["_forward"] = forward
return forward
def __getattr__(self, attr: str) -> Any:
if attr in self.__dir__():
return self.__getattribute__(
attr
) # make sure that appropriate exceptions are raised
elif attr.startswith("__"):
raise AttributeError(
"passing built-in private methods is "
f"not permitted with type {type(self)}. "
f"Got attribute {attr}."
)
elif "policy" in self.__dir__():
policy = self.__getattribute__("policy")
return getattr(policy, attr)
try:
super().__getattr__(attr)
except Exception:
raise AttributeError(
f"policy not set in {self.__class__.__name__}, cannot access {attr}."
)
