[RLlib] Fix connector examples (#27583)

rllib/BUILD

@@ -3343,36 +3343,36 @@ py_test(
 py_test(
     name = "examples/connectors/run_connector_policy",
     main = "examples/connectors/run_connector_policy.py",
-    tags = ["team:rllib", "exclusive", "examples", ],
+    tags = ["team:rllib", "exclusive", "examples", "examples_C", "examples_C_AtoT"],
     size = "small",
     srcs = ["examples/connectors/run_connector_policy.py"],
-    data = [
+    data = glob([
-        "tests/data/checkpoints/APPO_CartPole-v0_checkpoint-6",
+        "tests/data/checkpoints/APPO_CartPole-v0_checkpoint-6.new",
-    ],
+    ]),
-    args = ["--checkpoint_file=tests/data/checkpoints/APPO_CartPole-v0_checkpoint-6"]
+    args = ["--checkpoint_file=tests/data/checkpoints/APPO_CartPole-v0_checkpoint-6-08062022"]
 )
 
 py_test(
     name = "examples/connectors/adapt_connector_policy",
     main = "examples/connectors/adapt_connector_policy.py",
-    tags = ["team:rllib", "exclusive", "examples", ],
+    tags = ["team:rllib", "exclusive", "examples", "examples_C", "examples_C_AtoT"],
     size = "small",
     srcs = ["examples/connectors/adapt_connector_policy.py"],
-    data = [
+    data = glob([
-        "tests/data/checkpoints/APPO_CartPole-v0_checkpoint-6",
+        "tests/data/checkpoints/APPO_CartPole-v0_checkpoint-6.old",
-    ],
+    ]),
-    args = ["--checkpoint_file=tests/data/checkpoints/APPO_CartPole-v0_checkpoint-6"]
+    args = ["--checkpoint_file=tests/data/checkpoints/APPO_CartPole-v0_checkpoint-6-07092022"]
 )
 
 py_test(
     name = "examples/connectors/self_play_with_policy_checkpoint",
     main = "examples/connectors/self_play_with_policy_checkpoint.py",
-    tags = ["team:rllib", "exclusive", "examples", ],
+    tags = ["team:rllib", "exclusive", "examples", "examples_C", "examples_C_AtoT"],
     size = "small",
     srcs = ["examples/connectors/self_play_with_policy_checkpoint.py"],
-    data = [
+    data = glob([
         "tests/data/checkpoints/PPO_open_spiel_checkpoint-6",
-    ],
+    ]),
     args = [
         "--checkpoint_file=tests/data/checkpoints/PPO_open_spiel_checkpoint-6",
         "--train_iteration=1"  # Smoke test.

rllib/examples/connectors/adapt_connector_policy.py

@@ -5,6 +5,7 @@ and adapt/use it with a different version of the environment.
 import argparse
 import gym
 import numpy as np
+from pathlib import Path
 from typing import Dict
 
 from ray.rllib.utils.policy import (
@@ -23,9 +24,11 @@ from ray.rllib.utils.typing import (
 
 
 parser = argparse.ArgumentParser()
+# A policy checkpoint that works with this example script can be found at:
+# rllib/tests/data/checkpoints/APPO_CartPole-v0_checkpoint-6-07092022
 parser.add_argument(
     "--checkpoint_file",
-    help="Path to an RLlib checkpoint file.",
+    help="Path to an RLlib checkpoint file, relative to //ray/rllib/ folder.",
 )
 parser.add_argument(
     "--policy_id",
@@ -87,13 +90,21 @@ V1ToV2ActionConnector = register_lambda_action_connector(
 )
 
 
-def run():
+def run(checkpoint_path):
     # Restore policy.
-    policies = load_policies_from_checkpoint(args.checkpoint_file, [args.policy_id])
+    policies = load_policies_from_checkpoint(checkpoint_path, [args.policy_id])
     policy = policies[args.policy_id]
 
     # Adapt policy trained for standard CartPole to the new env.
     ctx: ConnectorContext = ConnectorContext.from_policy(policy)
+
+    # When this policy was trained, it relied on FlattenDataAgentConnector
+    # to add a batch dimension to single observations.
+    # This is not necessary anymore, so we first remove the previously used
+    # FlattenDataAgentConnector.
+    policy.agent_connectors.remove("FlattenDataAgentConnector")
+
+    # We then add the two adapter connectors.
     policy.agent_connectors.prepend(V2ToV1ObsAgentConnector(ctx))
     policy.action_connectors.append(V1ToV2ActionConnector(ctx))
 
@@ -115,4 +126,7 @@ def run():
 
 
 if __name__ == "__main__":
-    run()
+    checkpoint_path = str(
+        Path(__file__).parent.parent.parent.absolute().joinpath(args.checkpoint_file)
+    )
+    run(checkpoint_path)

rllib/examples/connectors/run_connector_policy.py

@@ -4,6 +4,7 @@ and use it in a serving/inference setting.
 
 import argparse
 import gym
+from pathlib import Path
 
 from ray.rllib.utils.policy import (
     load_policies_from_checkpoint,
@@ -15,7 +16,7 @@ parser = argparse.ArgumentParser()
 # This should a checkpoint created with connectors enabled.
 parser.add_argument(
     "--checkpoint_file",
-    help="Path to an RLlib checkpoint file.",
+    help="Path to an RLlib checkpoint file, relative to //ray/rllib/ folder.",
 )
 parser.add_argument(
     "--policy_id",
@@ -27,9 +28,9 @@ args = parser.parse_args()
 assert args.checkpoint_file, "Must specify flag --checkpoint_file."
 
 
-def run():
+def run(checkpoint_path):
     # Restore policy.
-    policies = load_policies_from_checkpoint(args.checkpoint_file, [args.policy_id])
+    policies = load_policies_from_checkpoint(checkpoint_path, [args.policy_id])
     policy = policies[args.policy_id]
 
     # Run CartPole.
@@ -52,4 +53,7 @@ def run():
 
 
 if __name__ == "__main__":
-    run()
+    checkpoint_path = str(
+        Path(__file__).parent.parent.parent.absolute().joinpath(args.checkpoint_file)
+    )
+    run(checkpoint_path)

rllib/examples/connectors/self_play_with_policy_checkpoint.py

@@ -4,6 +4,7 @@ The checkpointed policy may be trained with a different algorithm too.
 """
 
 import argparse
+from pathlib import Path
 import pyspiel
 
 import ray
@@ -23,7 +24,10 @@ parser.add_argument(
     "--checkpoint_file",
     type=str,
     default="",
-    help="Path to a connector enabled checkpoint file for restoring.",
+    help=(
+        "Path to a connector enabled checkpoint file for restoring,"
+        "relative to //ray/rllib/ folder."
+    ),
 )
 parser.add_argument(
     "--policy_id",
@@ -46,8 +50,13 @@ class AddPolicyCallback(DefaultCallbacks):
         super().__init__()
 
     def on_algorithm_init(self, *, algorithm, **kwargs):
+        checkpoint_path = str(
+            Path(__file__)
+            .parent.parent.parent.absolute()
+            .joinpath(args.checkpoint_file)
+        )
         policy_config, policy_specs, policy_states = parse_policy_specs_from_checkpoint(
-            args.checkpoint_file
+            checkpoint_path
         )
 
         assert args.policy_id in policy_specs, (

rllib/utils/policy.py

@@ -1,5 +1,5 @@
 import gym
-import pickle
+import ray.cloudpickle as pickle
 from typing import Callable, Dict, List, Optional, Tuple, Union, TYPE_CHECKING
 
 from ray.rllib.policy.policy import PolicySpec