Files
lerobot/src/lerobot/envs/utils.py
T
Khalil Meftah 552b4c3563 Add third-party env plugin discovery (#3823)
* feat(envs): add env plugin discovery

- Add 'lerobot_env_' to third-party plugin discovery prefixes, completing
the plugin system for all component types (robots, cameras, teleoperators,
policies, and now environments). External packages named lerobot_env_*
can self-register EnvConfig subclasses on import, enabling --env.type=
resolution without lerobot code changes.

* feat(envs): add generic observation passthrough

- Add generic observation passthrough in preprocess_observation() for
unhandled ndarray/tensor keys, replacing the pattern of adding per-env
hardcoded key handlers. Extra keys are forwarded as observation.<key>
and can be shaped by env-specific ProcessorSteps via get_env_processors().

---------

Co-authored-by: Steven Palma <imstevenpmwork@ieee.org>
2026-06-19 18:30:00 +02:00

424 lines
16 KiB
Python
Raw Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
#!/usr/bin/env python
# Copyright 2024 The HuggingFace Inc. team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import importlib.util
import os
import warnings
from collections.abc import Callable, Mapping, Sequence
from functools import singledispatch
from typing import Any
import einops
import gymnasium as gym
import numpy as np
import torch
from huggingface_hub import hf_hub_download, snapshot_download
from torch import Tensor
from lerobot.configs import FeatureType, PolicyFeature
from lerobot.utils.constants import OBS_ENV_STATE, OBS_IMAGE, OBS_IMAGES, OBS_STATE, OBS_STR
from lerobot.utils.utils import get_channel_first_image_shape
from .configs import EnvConfig
def parse_camera_names(camera_name: str | Sequence[str]) -> list[str]:
"""Normalize ``camera_name`` into a non-empty list of strings.
Accepts a comma-separated string (``"cam_a,cam_b"``) or a sequence of
strings (tuples/lists). Whitespace is stripped; empty entries are
dropped. Raises ``TypeError`` for unsupported input types and
``ValueError`` when the normalized list is empty.
"""
if isinstance(camera_name, str):
cams = [c.strip() for c in camera_name.split(",") if c.strip()]
elif isinstance(camera_name, (list | tuple)):
cams = [str(c).strip() for c in camera_name if str(c).strip()]
else:
raise TypeError(f"camera_name must be str or sequence[str], got {type(camera_name).__name__}")
if not cams:
raise ValueError("camera_name resolved to an empty list.")
return cams
def _convert_nested_dict(d):
result = {}
for k, v in d.items():
if isinstance(v, dict):
result[k] = _convert_nested_dict(v)
elif isinstance(v, np.ndarray):
result[k] = torch.from_numpy(v)
else:
result[k] = v
return result
def preprocess_observation(observations: dict[str, np.ndarray]) -> dict[str, Tensor]:
# TODO(jadechoghari, imstevenpmwork): refactor this to use features from the environment (no hardcoding)
"""Convert environment observation to LeRobot format observation.
Args:
observation: Dictionary of observation batches from a Gym vector environment.
Returns:
Dictionary of observation batches with keys renamed to LeRobot format and values as tensors.
"""
# map to expected inputs for the policy
return_observations = {}
if "pixels" in observations:
if isinstance(observations["pixels"], dict):
imgs = {f"{OBS_IMAGES}.{key}": img for key, img in observations["pixels"].items()}
else:
imgs = {OBS_IMAGE: observations["pixels"]}
for imgkey, img in imgs.items():
# TODO(aliberts, rcadene): use transforms.ToTensor()?
img_tensor = torch.from_numpy(img)
# When preprocessing observations in a non-vectorized environment, we need to add a batch dimension.
# This is the case for human-in-the-loop RL where there is only one environment.
if img_tensor.ndim == 3:
img_tensor = img_tensor.unsqueeze(0)
# sanity check that images are channel last
_, h, w, c = img_tensor.shape
assert c < h and c < w, f"expect channel last images, but instead got {img_tensor.shape=}"
# sanity check that images are uint8
assert img_tensor.dtype == torch.uint8, f"expect torch.uint8, but instead {img_tensor.dtype=}"
# convert to channel first of type float32 in range [0,1]
img_tensor = einops.rearrange(img_tensor, "b h w c -> b c h w").contiguous()
img_tensor = img_tensor.type(torch.float32)
img_tensor /= 255
return_observations[imgkey] = img_tensor
if "environment_state" in observations:
env_state = torch.from_numpy(observations["environment_state"]).float()
if env_state.dim() == 1:
env_state = env_state.unsqueeze(0)
return_observations[OBS_ENV_STATE] = env_state
if "agent_pos" in observations:
agent_pos = torch.from_numpy(observations["agent_pos"]).float()
if agent_pos.dim() == 1:
agent_pos = agent_pos.unsqueeze(0)
return_observations[OBS_STATE] = agent_pos
if "robot_state" in observations:
return_observations[f"{OBS_STR}.robot_state"] = _convert_nested_dict(observations["robot_state"])
# Handle IsaacLab Arena format: observations have 'policy' and 'camera_obs' keys
if "policy" in observations:
return_observations[f"{OBS_STR}.policy"] = observations["policy"]
if "camera_obs" in observations:
return_observations[f"{OBS_STR}.camera_obs"] = observations["camera_obs"]
# Pass through any remaining ndarray/tensor keys not already handled above,
# so env plugins can expose extra observation keys via get_env_processors().
_handled = {"pixels", "environment_state", "agent_pos", "robot_state", "policy", "camera_obs"}
for key, value in observations.items():
if key in _handled:
continue
target = f"{OBS_STR}.{key}"
if target in return_observations:
continue
if isinstance(value, np.ndarray):
val = torch.from_numpy(value).float()
if val.dim() == 1:
val = val.unsqueeze(0)
return_observations[target] = val
elif isinstance(value, Tensor):
val = value.float()
if val.dim() == 1:
val = val.unsqueeze(0)
return_observations[target] = val
return return_observations
def env_to_policy_features(env_cfg: EnvConfig) -> dict[str, PolicyFeature]:
# TODO(jadechoghari, imstevenpmwork): remove this hardcoding of keys and just use the nested keys as is
# (need to also refactor preprocess_observation and externalize normalization from policies)
policy_features = {}
for key, ft in env_cfg.features.items():
if ft.type is FeatureType.VISUAL:
if len(ft.shape) != 3:
raise ValueError(f"Number of dimensions of {key} != 3 (shape={ft.shape})")
shape = get_channel_first_image_shape(ft.shape)
feature = PolicyFeature(type=ft.type, shape=shape)
else:
feature = ft
policy_key = env_cfg.features_map[key]
policy_features[policy_key] = feature
return policy_features
def _sub_env_has_attr(env: gym.vector.VectorEnv, attr: str) -> bool:
try:
env.get_attr(attr)
return True
except (AttributeError, Exception):
return False
class _LazyAsyncVectorEnv:
"""Defers AsyncVectorEnv creation until first use.
Creating all tasks' AsyncVectorEnvs upfront spawns N_tasks × n_envs worker
processes, all of which allocate EGL/GPU resources immediately. Since tasks
are evaluated sequentially, only one task's workers need to be alive at a
time. This wrapper stores the factory functions and creates the real
AsyncVectorEnv on first reset()/step()/call(), keeping peak process count = n_envs.
"""
def __init__(
self,
env_fns: list[Callable],
observation_space=None,
action_space=None,
metadata=None,
):
self._env_fns = env_fns
self._env: gym.vector.AsyncVectorEnv | None = None
self.num_envs = len(env_fns)
if observation_space is not None and action_space is not None and metadata is not None:
self.observation_space = observation_space
self.action_space = action_space
self.metadata = metadata
else:
tmp = env_fns[0]()
self.observation_space = tmp.observation_space
self.action_space = tmp.action_space
self.metadata = tmp.metadata
tmp.close()
self.single_observation_space = self.observation_space
self.single_action_space = self.action_space
def _ensure(self) -> None:
if self._env is None:
self._env = gym.vector.AsyncVectorEnv(self._env_fns, context="forkserver", shared_memory=True)
@property
def unwrapped(self):
return self
def reset(self, **kwargs):
self._ensure()
return self._env.reset(**kwargs)
def step(self, actions):
self._ensure()
return self._env.step(actions)
def call(self, name, *args, **kwargs):
self._ensure()
return self._env.call(name, *args, **kwargs)
def get_attr(self, name):
self._ensure()
return self._env.get_attr(name)
def close(self) -> None:
if self._env is not None:
self._env.close()
self._env = None
def check_env_attributes_and_types(env: gym.vector.VectorEnv) -> None:
with warnings.catch_warnings():
warnings.simplefilter("once", UserWarning)
if not (_sub_env_has_attr(env, "task_description") and _sub_env_has_attr(env, "task")):
warnings.warn(
"The environment does not have 'task_description' and 'task'. Some policies require these features.",
UserWarning,
stacklevel=2,
)
def _close_single_env(env: Any) -> None:
try:
env.close()
except Exception as exc:
print(f"Exception while closing env {env}: {exc}")
@singledispatch
def close_envs(obj: Any) -> None:
"""Default: raise if the type is not recognized."""
raise NotImplementedError(f"close_envs not implemented for type {type(obj).__name__}")
@close_envs.register
def _(env: Mapping) -> None:
for v in env.values():
if isinstance(v, Mapping):
close_envs(v)
elif hasattr(v, "close"):
_close_single_env(v)
@close_envs.register
def _(envs: Sequence) -> None:
if isinstance(envs, (str | bytes)):
return
for v in envs:
if isinstance(v, Mapping) or isinstance(v, Sequence) and not isinstance(v, (str | bytes)):
close_envs(v)
elif hasattr(v, "close"):
_close_single_env(v)
@close_envs.register
def _(env: gym.Env) -> None:
_close_single_env(env)
# helper to safely load a python file as a module
def _load_module_from_path(path: str, module_name: str | None = None):
module_name = module_name or f"hub_env_{os.path.basename(path).replace('.', '_')}"
spec = importlib.util.spec_from_file_location(module_name, path)
if spec is None:
raise ImportError(f"Could not load module spec for {module_name} from {path}")
module = importlib.util.module_from_spec(spec)
spec.loader.exec_module(module) # type: ignore
return module
# helper to parse hub string (supports "user/repo", "user/repo@rev", optional path)
# examples:
# "user/repo" -> will look for env.py at repo root
# "user/repo@main:envs/my_env.py" -> explicit revision and path
def _parse_hub_url(hub_uri: str):
# very small parser: [repo_id][@revision][:path]
# repo_id is required (user/repo or org/repo)
revision = None
file_path = "env.py"
if "@" in hub_uri:
repo_and_rev, *rest = hub_uri.split(":", 1)
repo_id, rev = repo_and_rev.split("@", 1)
revision = rev
if rest:
file_path = rest[0]
else:
repo_id, *rest = hub_uri.split(":", 1)
if rest:
file_path = rest[0]
return repo_id, revision, file_path
def _download_hub_file(
cfg_str: str,
trust_remote_code: bool,
hub_cache_dir: str | None,
) -> tuple[str, str, str, str]:
"""
Parse `cfg_str` (hub URL), enforce `trust_remote_code`, and return
(repo_id, file_path, local_file, revision).
"""
if not trust_remote_code:
raise RuntimeError(
f"Refusing to execute remote code from the Hub for '{cfg_str}'. "
"Executing hub env modules runs arbitrary Python code from third-party repositories. "
"If you trust this repo and understand the risks, call `make_env(..., trust_remote_code=True)` "
"and prefer pinning to a specific revision: 'user/repo@<commit-hash>:env.py'."
)
repo_id, revision, file_path = _parse_hub_url(cfg_str)
try:
local_file = hf_hub_download(
repo_id=repo_id, filename=file_path, revision=revision, cache_dir=hub_cache_dir
)
except Exception as e:
# fallback to snapshot download
snapshot_dir = snapshot_download(repo_id=repo_id, revision=revision, cache_dir=hub_cache_dir)
local_file = os.path.join(snapshot_dir, file_path)
if not os.path.exists(local_file):
raise FileNotFoundError(
f"Could not find {file_path} in repository {repo_id}@{revision or 'main'}"
) from e
return repo_id, file_path, local_file, revision
def _import_hub_module(local_file: str, repo_id: str) -> Any:
"""
Import the downloaded file as a module and surface helpful import error messages.
"""
module_name = f"hub_env_{repo_id.replace('/', '_')}"
try:
module = _load_module_from_path(local_file, module_name=module_name)
except ModuleNotFoundError as e:
missing = getattr(e, "name", None) or str(e)
raise ModuleNotFoundError(
f"Hub env '{repo_id}:{os.path.basename(local_file)}' failed to import because the dependency "
f"'{missing}' is not installed locally.\n\n"
) from e
except ImportError as e:
raise ImportError(
f"Failed to load hub env module '{repo_id}:{os.path.basename(local_file)}'. Import error: {e}\n\n"
) from e
return module
def _call_make_env(module: Any, n_envs: int, use_async_envs: bool, cfg: EnvConfig | None) -> Any:
"""
Ensure module exposes make_env and call it.
"""
if not hasattr(module, "make_env"):
raise AttributeError(
f"The hub module {getattr(module, '__name__', 'hub_module')} must expose `make_env(n_envs=int, use_async_envs=bool)`."
)
entry_fn = module.make_env
# Only pass cfg if it's not None (i.e., when an EnvConfig was provided, not a string hub ID)
if cfg is not None:
return entry_fn(n_envs=n_envs, use_async_envs=use_async_envs, cfg=cfg)
else:
return entry_fn(n_envs=n_envs, use_async_envs=use_async_envs)
def _normalize_hub_result(result: Any) -> dict[str, dict[int, gym.vector.VectorEnv]]:
"""
Normalize possible return types from hub `make_env` into the mapping:
{ suite_name: { task_id: vector_env } }
Accepts:
- dict (assumed already correct)
- gym.vector.VectorEnv
- gym.Env (will be wrapped into SyncVectorEnv)
"""
if isinstance(result, dict):
return result
# VectorEnv: use its spec.id if available
if isinstance(result, gym.vector.VectorEnv):
suite_name = getattr(result, "spec", None) and getattr(result.spec, "id", None) or "hub_env"
return {suite_name: {0: result}}
# Single Env: wrap into SyncVectorEnv
if isinstance(result, gym.Env):
vec = gym.vector.SyncVectorEnv([lambda: result])
suite_name = getattr(result, "spec", None) and getattr(result.spec, "id", None) or "hub_env"
return {suite_name: {0: vec}}
raise ValueError(
"Hub `make_env` must return either a mapping {suite: {task_id: vec_env}}, "
"a gym.vector.VectorEnv, or a single gym.Env."
)