Add unit tests for saving/loading model

model/orbax/experimental/model/core/python/__init__.py

@@ -35,9 +35,10 @@
 from orbax.experimental.model.core.python.function import ShloShape
 from orbax.experimental.model.core.python.function import ShloTensorSpec
 from orbax.experimental.model.core.python.manifest_constants import *
-from orbax.experimental.model.core.python.save_lib import GlobalSupplemental
-from orbax.experimental.model.core.python.save_lib import save
-from orbax.experimental.model.core.python.save_lib import SaveOptions
+from orbax.experimental.model.core.python.persistence_lib import GlobalSupplemental
+from orbax.experimental.model.core.python.persistence_lib import load
+from orbax.experimental.model.core.python.persistence_lib import save
+from orbax.experimental.model.core.python.persistence_lib import SaveOptions
 from orbax.experimental.model.core.python.saveable import Saveable
 from orbax.experimental.model.core.python.serializable_function import SerializableFunction
 from orbax.experimental.model.core.python.shlo_function import ShloFunction

model/orbax/experimental/model/core/python/file_utils.py

@@ -15,9 +15,11 @@
 """File utilities."""
 
 import contextlib
-
+import os
 
 _file_opener = open
+_mkdir_p = lambda path: os.makedirs(path, exist_ok=True)
+
 
 
 @contextlib.contextmanager
@@ -28,3 +30,8 @@ def open_file(filename: str, mode: str):
     yield f
   finally:
     f.close()
+
+
+def mkdir_p(path: str) -> None:
+  """Creates a directory, creating parent directories as needed."""
+  _mkdir_p(path)

model/orbax/experimental/model/core/python/manifest_constants.py

@@ -14,18 +14,15 @@
 
 """Manifest model format constants."""
 
-MANIFEST_VERSION_FILENAME = 'orbax_model_version.txt'
+# The filename of the model version metadata file relative to the save
+# directory.
+MODEL_VERSION_FILENAME = 'orbax_model_version.txt'
 
-# The file path of the manifest proto file
-MANIFEST_FILE_PATH_KEY = 'manifest_file_path'
-# TODO(b/439870164): Update the `MANIFEST_FILENAME` to be `MANIFEST_FILE_PATH`
-# and treat it as a configurable path
-MANIFEST_FILENAME = 'manifest.pb'
+# The file path of the manifest proto file relative to the save directory.
+MANIFEST_FILE_PATH = 'manifest.pb'
 
-# The version of the manifest
-VERSION_KEY = 'version'
+# The version of the manifest.
 MANIFEST_VERSION = '0.0.1'
 
-# The mime type of the manifest proto file
-MIME_TYPE_KEY = 'mime_type'
+# The mime type of the manifest proto file.
 MANIFEST_MIME_TYPE = 'application/protobuf; type=orbax_model_manifest.Manifest'

model/orbax/experimental/model/core/python/manifest_util.py

@@ -18,7 +18,6 @@
 from collections.abc import Mapping, Sequence
 from absl import logging
 from orbax.experimental.model.core.protos import manifest_pb2
-from orbax.experimental.model.core.python import manifest_constants
 from orbax.experimental.model.core.python import unstructured_data
 from orbax.experimental.model.core.python.device_assignment import DeviceAssignment
 from orbax.experimental.model.core.python.function import Function
@@ -29,6 +28,7 @@
 from orbax.experimental.model.core.python.unstructured_data import UnstructuredData
 from orbax.experimental.model.core.python.value import ExternalValue
 
+
 def _build_function(
     fn: Function,
     path: str,
@@ -63,7 +63,7 @@ def _build_function(
         supp_proto = supp.proto
         if supp.ext_name is not None:
           filename = unstructured_data.build_filename_from_extension(
-              name + "_supplemental", supp.ext_name
+              name + "_" + supp_name + "_supplemental", supp.ext_name
           )
           supp_proto = unstructured_data.write_inlined_data_to_file(
               supp_proto, path, filename
@@ -115,28 +115,6 @@ def _is_seq_of_functions(obj: Saveable) -> bool:
   )
 
 
-def build_manifest_version_file() -> str:
-  """Builds a manifest version file content."""
-
-  # TODO(b/365967674): Remove this check once the manifest filename is
-  # configurable by the manifest version file. Currently, the manifest filename
-  # is hardcoded to "manifest.pb" in OBM & JSV codebase and that needs to be
-  # updated first.
-  if manifest_constants.MANIFEST_FILENAME != "manifest.pb":
-    raise ValueError(
-        "Currently, only manifest.pb is supported as the manifest filename."
-    )
-
-  return (
-      f"{manifest_constants.MANIFEST_FILE_PATH_KEY}:"
-      f' "{manifest_constants.MANIFEST_FILENAME}"\n'
-      f"{manifest_constants.VERSION_KEY}:"
-      f' "{manifest_constants.MANIFEST_VERSION}"\n'
-      f"{manifest_constants.MIME_TYPE_KEY}:"
-      f' "{manifest_constants.MANIFEST_MIME_TYPE}"\n'
-  )
-
-
 def build_manifest_proto(
     obm_module: dict[str, Saveable],
     path: str,

model/orbax/experimental/model/core/python/manifest_util_test.py

@@ -64,15 +64,5 @@ def test_build_device_assignment_by_coords_proto(self):
       self.assertEqual(device.core_on_chip, 0)  # Proto default
 
 
-def test_build_manifest_version_file_content(self):
-  content = manifest_util.build_manifest_version_file()
-  expected_content = (
-      'manifest_file_path: "manifest.pb"\n'
-      'version: "0.0.1"\n'
-      'mime_type: "application/protobuf; type=orbax_model_manifest.Manifest"\n'
-  )
-  self.assertEqual(content, expected_content)
-
-
 if __name__ == '__main__':
   absltest.main()

model/orbax/experimental/model/core/python/metadata.py

@@ -0,0 +1,84 @@
+# 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.
+
+"""Model version metadata and its serialization."""
+
+import dataclasses
+from orbax.experimental.model.core.python import file_utils
+
+
+@dataclasses.dataclass
+class ModelVersion:
+  """Model version metadata."""
+
+  _VERSION_KEY = 'version'
+  _MIME_TYPE_KEY = 'mime_type'
+  _MANIFEST_FILE_PATH_KEY = 'manifest_file_path'
+
+  version: str
+  mime_type: str
+  manifest_file_path: str
+
+  def save(self, path: str) -> None:
+    """Saves the model version metadata to a file."""
+    with file_utils.open_file(path, 'w') as f:
+      f.write(f'{self._MANIFEST_FILE_PATH_KEY}: "{self.manifest_file_path}"\n')
+      f.write(f'{self._VERSION_KEY}: "{self.version}"\n')
+      f.write(f'{self._MIME_TYPE_KEY}: "{self.mime_type}"\n')
+
+  @classmethod
+  def load(cls, path: str) -> 'ModelVersion':
+    """Loads the model version metadata from a file."""
+
+    version = ''
+    mime_type = ''
+    manifest_file_path = ''
+
+    with file_utils.open_file(path, 'r') as f:
+      for line in f:
+        line = line.strip()
+        if not line:
+          continue
+        if ':' not in line:
+          raise ValueError(f'Malformed line: {line}')
+
+        key, value = line.split(':', 1)
+        key = key.strip()
+        value = value.strip()
+
+        if not value.startswith('"') or not value.endswith('"'):
+          raise ValueError('All values must be double-quoted')
+
+        value = value[1:-1]
+        if key == cls._MANIFEST_FILE_PATH_KEY:
+          manifest_file_path = value
+        elif key == cls._VERSION_KEY:
+          version = value
+        elif key == cls._MIME_TYPE_KEY:
+          mime_type = value
+        else:
+          raise ValueError(f'Unknown key: {key}')
+
+      if not version:
+        raise ValueError('Version is empty')
+      if not mime_type:
+        raise ValueError('MIME type is empty')
+      if not manifest_file_path:
+        raise ValueError('Manifest file path is empty')
+
+      return cls(
+          version=version,
+          mime_type=mime_type,
+          manifest_file_path=manifest_file_path,
+      )

model/orbax/experimental/model/core/python/metadata_test.py

@@ -0,0 +1,116 @@
+# 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.
+
+import os
+from absl.testing import absltest
+from orbax.experimental.model.core.python import file_utils
+from orbax.experimental.model.core.python import metadata
+
+
+class MetadataTest(absltest.TestCase):
+
+  def test_save_and_load(self):
+    tempdir = self.create_tempdir().full_path
+    path = os.path.join(tempdir, 'orbax_model_version.txt')
+    mv = metadata.ModelVersion(
+        version='1', mime_type='test_mime_type', manifest_file_path='test/path'
+    )
+    mv.save(path)
+    mv_loaded = metadata.ModelVersion.load(path)
+    self.assertEqual(mv_loaded, mv)
+
+  def test_load_fails_with_unknown_fields(self):
+    tempdir = self.create_tempdir().full_path
+    path = os.path.join(tempdir, 'orbax_model_version.txt')
+    file_content = """
+    manifest_file_path: "test/path"
+    version: "0.0.1"
+    mime_type: "test_mime_type; application/foo"
+    unknown_field: unknown_value
+    """
+    with file_utils.open_file(path, 'w') as f:
+      f.write(file_content)
+
+    with self.assertRaises(ValueError):
+      metadata.ModelVersion.load(path)
+
+  def test_load_fails_with_single_quoted_values(self):
+    tempdir = self.create_tempdir().full_path
+    path = os.path.join(tempdir, 'orbax_model_version.txt')
+    file_content = """
+    manifest_file_path: "test/path"
+    version: '0.0.1'
+    mime_type: "test_mime_type; application/foo"
+    """
+    with file_utils.open_file(path, 'w') as f:
+      f.write(file_content)
+
+    with self.assertRaises(ValueError):
+      metadata.ModelVersion.load(path)
+
+  def test_load_fails_with_malformed_file(self):
+    tempdir = self.create_tempdir().full_path
+    path = os.path.join(tempdir, 'orbax_model_version.txt')
+    file_content = """
+    manifest_file_path: "test/path"
+    malformed_line_no_separator
+    """
+    with file_utils.open_file(path, 'w') as f:
+      f.write(file_content)
+
+    with self.assertRaises(ValueError):
+      metadata.ModelVersion.load(path)
+
+  def test_missing_version(self):
+    tempdir = self.create_tempdir().full_path
+    path = os.path.join(tempdir, 'orbax_model_version.txt')
+    file_content = """
+    manifest_file_path: "test/path"
+    mime_type: "test_mime_type; application/foo"
+    """
+    with file_utils.open_file(path, 'w') as f:
+      f.write(file_content)
+
+    with self.assertRaisesRegex(ValueError, 'Version is empty'):
+      metadata.ModelVersion.load(path)
+
+  def test_missing_mime_type(self):
+    tempdir = self.create_tempdir().full_path
+    path = os.path.join(tempdir, 'orbax_model_version.txt')
+    file_content = """
+    version: "0.0.1"
+    manifest_file_path: "test/path"
+    """
+    with file_utils.open_file(path, 'w') as f:
+      f.write(file_content)
+
+    with self.assertRaisesRegex(ValueError, 'MIME type is empty'):
+      metadata.ModelVersion.load(path)
+
+  def test_missing_manifest_file_path(self):
+    tempdir = self.create_tempdir().full_path
+    path = os.path.join(tempdir, 'orbax_model_version.txt')
+    file_content = """
+    version: "0.0.1"
+    mime_type: "test_mime_type; application/foo"
+    """
+    with file_utils.open_file(path, 'w') as f:
+      f.write(file_content)
+
+    with self.assertRaisesRegex(ValueError, 'Manifest file path is empty'):
+      metadata.ModelVersion.load(path)
+
+
+if __name__ == '__main__':
+  absltest.main()