FEAT-#4245: Define base interface for dataframe exchange protocol

.github/workflows/ci.yml

@@ -256,6 +256,7 @@ jobs:
       - run: python -m pytest -n 2 modin/test/test_partition_api.py
       - run: python -m pytest modin/test/test_utils.py
       - run: python -m pytest asv_bench/test/test_utils.py
+      - run: python -m pytest modin/test/exchange/dataframe_protocol/base
       - uses: codecov/codecov-action@v2
 
   test-defaults:

.github/workflows/push.yml

@@ -29,6 +29,7 @@ jobs:
       - run: python -m pytest modin/test/storage_formats/pandas/test_internals.py
       - run: python -m pytest modin/test/test_envvar_npartitions.py
       - run: python -m pytest modin/test/test_partition_api.py
+      - run: python -m pytest modin/test/exchange/dataframe_protocol/base
       - uses: codecov/codecov-action@v2
 
   test-defaults:

docs/release_notes/release_notes-0.14.0.rst

@@ -31,7 +31,7 @@ Key Features and Updates
 * XGBoost enhancements
   *
 * Developer API enhancements
-  *
+  * FEAT-#4245: Define base interface for dataframe exchange protocol (#4246)
 * Update testing suite
   * TEST-#3628: Report coverage data for `test-internals` CI job (#4198)
   * TEST-#3938: Test tutorial notebooks in CI (#4145)

modin/conftest.py

@@ -44,6 +44,7 @@ def _saving_make_api_url(token, _make_api_url=modin.utils._make_api_url):
 import modin  # noqa: E402
 import modin.config  # noqa: E402
 from modin.config import IsExperimental, TestRayClient  # noqa: E402
+import uuid  # noqa: E402
 
 from modin.core.storage_formats import (  # noqa: E402
     PandasQueryCompiler,
@@ -233,6 +234,17 @@ def from_arrow(cls, at, data_cls):
     def free(self):
         pass
 
+    def to_dataframe(self, nan_as_null: bool = False, allow_copy: bool = True) -> dict:
+        raise NotImplementedError(
+            "The selected execution does not implement the DataFrame exchange protocol."
+        )
+
+    @classmethod
+    def from_dataframe(cls, df, data_cls):
+        raise NotImplementedError(
+            "The selected execution does not implement the DataFrame exchange protocol."
+        )
+
     to_pandas = PandasQueryCompiler.to_pandas
     default_to_pandas = PandasQueryCompiler.default_to_pandas
 
@@ -252,6 +264,41 @@ def set_base_execution(name=BASE_EXECUTION_NAME):
     modin.set_execution(engine="python", storage_format=name.split("On")[0])
 
 
+@pytest.fixture(scope="function")
+def get_unique_base_execution():
+    """Setup unique execution for a single function and yield its QueryCompiler that's suitable for inplace modifications."""
+    # It's better to use decimal IDs rather than hex ones due to factory names formatting
+    execution_id = int(uuid.uuid4().hex, 16)
+    format_name = f"Base{execution_id}"
+    engine_name = "Python"
+    execution_name = f"{format_name}On{engine_name}"
+
+    # Dynamically building all the required classes to form a new execution
+    base_qc = type(format_name, (TestQC,), {})
+    base_io = type(
+        f"{execution_name}IO", (BaseOnPythonIO,), {"query_compiler_cls": base_qc}
+    )
+    base_factory = type(
+        f"{execution_name}Factory",
+        (BaseOnPythonFactory,),
+        {"prepare": classmethod(lambda cls: setattr(cls, "io_cls", base_io))},
+    )
+
+    # Setting up the new execution
+    setattr(factories, f"{execution_name}Factory", base_factory)
+    old_engine, old_format = modin.set_execution(
+        engine=engine_name, storage_format=format_name
+    )
+    yield base_qc
+
+    # Teardown the new execution
+    modin.set_execution(engine=old_engine, storage_format=old_format)
+    try:
+        delattr(factories, f"{execution_name}Factory")
+    except AttributeError:
+        pass
+
+
 def pytest_configure(config):
     if config.option.extra_test_parameters is not None:
         import modin.pandas.test.utils as utils

modin/core/dataframe/base/exchange/__init__.py

@@ -0,0 +1,14 @@
+# Licensed to Modin Development Team under one or more contributor license agreements.
+# See the NOTICE file distributed with this work for additional information regarding
+# copyright ownership.  The Modin Development Team licenses this file to you 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.
+
+"""Base Modin Dataframe functionality related to data exchange protocols."""

modin/core/dataframe/base/exchange/dataframe_protocol/__init__.py

@@ -0,0 +1,22 @@
+# Licensed to Modin Development Team under one or more contributor license agreements.
+# See the NOTICE file distributed with this work for additional information regarding
+# copyright ownership.  The Modin Development Team licenses this file to you 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.
+
+"""
+Base Modin Dataframe functionality related to the dataframe exchange protocol.
+
+See more in https://data-apis.org/dataframe-protocol/latest/index.html.
+"""
+
+from .dataframe import ProtocolDataframe
+
+__all__ = ["ProtocolDataframe"]