feat: add metadata bridge for Python CUDA export

vortex-cuda/src/arrow/mod.rs

@@ -543,14 +543,14 @@ fn released_device_array(device_id: i64) -> ArrowDeviceArray {
 }
 
 /// Release an Arrow C schema if it is live.
-fn release_schema(schema: &mut FFI_ArrowSchema) {
+pub fn release_schema(schema: &mut FFI_ArrowSchema) {
     if let Some(release) = schema.release {
         unsafe { release(schema) };
     }
 }
 
 /// Release an Arrow device array if it is live.
-fn release_device_array(array: &mut ArrowDeviceArray) {
+pub fn release_device_array(array: &mut ArrowDeviceArray) {
     if let Some(release) = array.array.release {
         unsafe { release(&raw mut array.array) };
     }

vortex-python-cuda/Cargo.toml

@@ -27,5 +27,7 @@ default = ["extension-module"]
 extension-module = []
 
 [dependencies]
+arrow-schema = { workspace = true }
 pyo3 = { workspace = true, features = ["abi3", "abi3-py311"] }
+vortex = { workspace = true }
 vortex-cuda = { workspace = true }

vortex-python-cuda/pyproject.toml

@@ -4,8 +4,9 @@ name = "vortex-data-cuda"
 dynamic = ["version", "description", "authors"]
 requires-python = ">= 3.11"
 # The CUDA extension package must exactly match the base package version because the two extensions
-# exchange Vortex IPC buffers. Keep this in sync with the workspace package version; release
-# automation may rewrite it when publishing a non-workspace version.
+# exchange private Vortex vtable metadata. Future buffer-handoff support will extend this private
+# bridge. Keep this in sync with the workspace package version; release automation may rewrite it
+# when publishing a non-workspace version.
 dependencies = ["vortex-data==0.1.0"]
 classifiers = [
     "Development Status :: 4 - Beta",

vortex-python-cuda/python/vortex_cuda/__init__.py

@@ -1,6 +1,12 @@
 # SPDX-License-Identifier: Apache-2.0
 # SPDX-FileCopyrightText: Copyright the Vortex contributors
 
-from ._lib import cuda_available  # pyright: ignore[reportMissingModuleSource]
+from ._lib import (  # pyright: ignore[reportMissingModuleSource]
+    _debug_array_metadata_dtype as _debug_array_metadata_dtype,
+)
+from ._lib import (
+    cuda_available,
+    export_device_array,
+)
 
-__all__ = ["cuda_available"]
+__all__ = ["cuda_available", "export_device_array"]

vortex-python-cuda/python/vortex_cuda/_lib.pyi

@@ -1,4 +1,8 @@
 #  SPDX-License-Identifier: Apache-2.0
 #  SPDX-FileCopyrightText: Copyright the Vortex contributors
 
+def _debug_array_metadata_dtype(array: object) -> str: ...
 def cuda_available() -> bool: ...
+def export_device_array(
+    array: object, requested_schema: object | None = None, **kwargs: object
+) -> tuple[object, object]: ...