#p2p Add Grain data iterator checkpointing to P2P

PiperOrigin-RevId: 863828755

Author: Orbax Authors

checkpoint/orbax/checkpoint/experimental/emergency/p2p/__init__.py

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+# Copyright 2025 The Orbax Authors.
+#
+# 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.
+

checkpoint/orbax/checkpoint/experimental/emergency/p2p/args.py

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+# Copyright 2025 The Orbax Authors.
+#
+# 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.
+
+"""P2P composite checkpoint argument."""
+
+from typing import Any, final
+
+from orbax.checkpoint import args as args_lib
+from orbax.checkpoint.experimental.emergency.p2p import constants
+from orbax.checkpoint.experimental.emergency.p2p import utils
+
+
+@final
+class Composite(args_lib.Composite):
+  """Composite argument that supports 'state' and 'data_iter' keys."""
+
+  def __init__(self, *args, **kwargs):
+    super().__init__(*args, **kwargs)
+    if constants.STATE_SUBDIR not in self:
+      raise ValueError(
+          f'Composite must contain "{constants.STATE_SUBDIR}" key:'
+          f' {list(self.keys())}'
+      )
+    for key in self:
+      if key not in [constants.STATE_SUBDIR, constants.DATA_ITER_KEY]:
+        raise ValueError(f'Unsupported key in Composite: {key}')
+      if key == constants.DATA_ITER_KEY:
+        if utils.pygrain() is None:
+          raise ImportError(
+              'grain library is not available. Please install grain'
+              ' to use data_iter.'
+          )
+        if not isinstance(
+            self[key],
+            (
+                utils.pygrain().PyGrainCheckpointSave,
+                utils.pygrain().PyGrainCheckpointRestore,
+            ),
+        ):
+          raise TypeError(f'Unsupported type for data_iter: {type(self[key])}')
+
+  def __setitem__(self, key: str, value: Any):
+    if key not in [constants.STATE_SUBDIR, constants.DATA_ITER_KEY]:
+      raise KeyError(
+          f'Invalid key: {key}. Only "{constants.STATE_SUBDIR}" and'
+          f' "{constants.DATA_ITER_KEY}" are supported.'
+      )
+    if key == constants.DATA_ITER_KEY:
+      if utils.pygrain() is None:
+        raise ImportError(
+            'grain library is not available. Please install grain'
+            ' to use data_iter.'
+        )
+      if not isinstance(
+          value,
+          (
+              utils.pygrain().PyGrainCheckpointSave,
+              utils.pygrain().PyGrainCheckpointRestore,
+          ),
+      ):
+        raise TypeError(f'Unsupported type for data_iter: {type(value)}')
+    self[key] = value