86 lines
2.9 KiB

from typing import Dict, Optional, Union
from ray.rllib.algorithms.dqn.dqn_torch_model import DQNTorchModel
from ray.rllib.models.torch.fcnet import FullyConnectedNetwork as TorchFC
from ray.rllib.models.tf.fcnet import FullyConnectedNetwork
from ray.rllib.models.torch.torch_modelv2 import TorchModelV2
from ray.rllib.utils.framework import try_import_tf, try_import_torch
from ray.rllib.utils.torch_utils import FLOAT_MIN, FLOAT_MAX
torch, nn = try_import_torch()
class TorchActionMaskModel(TorchModelV2, nn.Module):
"""PyTorch version of above ActionMaskingModel."""
def __init__(
self,
obs_space,
action_space,
num_outputs,
model_config,
name,
**kwargs,
):
orig_space = getattr(obs_space, "original_space", obs_space)
custom_config = model_config['custom_model_config']
print(F"Original Space is: {orig_space}")
#print(model_config)
print(F"Observation space in model: {obs_space}")
print(F"Provided action space in model {action_space}")
TorchModelV2.__init__(
self, obs_space, action_space, num_outputs, model_config, name, **kwargs
)
nn.Module.__init__(self)
assert("shield" in custom_config)
self.shield = custom_config["shield"]
self.count = 0
self.internal_model = TorchFC(
orig_space["data"],
action_space,
num_outputs,
model_config,
name + "_internal",
)
# disable action masking --> will likely lead to invalid actions
self.no_masking = False
if "no_masking" in model_config["custom_model_config"]:
self.no_masking = model_config["custom_model_config"]["no_masking"]
def forward(self, input_dict, state, seq_lens):
# Extract the available actions tensor from the observation.
# print(F"Input dict is {input_dict} at obs: {input_dict['obs']}")
# print(F"State is {state}")
# print(input_dict["env"])
# Compute the unmasked logits.
logits, _ = self.internal_model({"obs": input_dict["obs"]["data"]})
# print(F"Caluclated Logits {logits} with size {logits.size()} Count: {self.count}")
action_mask = input_dict["obs"]["avail_actions"]
#print(F"Action mask is {action_mask} with dimension {action_mask.size()}")
# If action masking is disabled, directly return unmasked logits
if self.no_masking:
return logits, state
# assert(False)
# Convert action_mask into a [0.0 || -inf]-type mask.
inf_mask = torch.clamp(torch.log(action_mask), min=FLOAT_MIN)
masked_logits = logits + inf_mask
print(F"Infinity mask {inf_mask}, Masked logits {masked_logits}")
# # Return masked logits.
return masked_logits, state
def value_function(self):
return self.internal_model.value_function()