[devin-ai-integration]

Summary

Moves the pure-Python Module (holoscan create --language python, #284) operator source next to its metadata. Each operator is gated on OP_<name> through add_holohub_operator(), as C++ operators are. The layout now matches the C++ and 4.x templates:

before                                         after
python/holoscan_<slug>/operators/__init__.py   operators/CMakeLists.txt        # add_holohub_operator(<op>)
python/holoscan_<slug>/operators/<op>.py       operators/__init__.py           # exports staged operators
operators/<op>/metadata.json                   operators/<op>/CMakeLists.txt   # holoscan_<slug>_add_python_operator()
                                               operators/<op>/__init__.py
                                               operators/<op>/<op>.py
                                               operators/<op>/metadata.json

python/holoscan_<slug>/ keeps only __init__.py and py.typed. Imports don't change: from holoscan_<slug>.operators import <Op> and import holoscan.<slug> both still work.

• Build tree: holoscan_<slug>_add_python_operator() (python/CMakeLists.txt) stages the calling operators/<op>/ sources as holoscan_<slug>.operators.<op>. Only operators whose OP_<op> is ON are staged. Each configure clears earlier staged operators.
• Wheel: it installs the CMake component, the same way the cpp python wheel does:

  wheel.packages = []
  wheel.platlib = false
  install.components = ["holoscan-<slug>-python_libs"]
  cmake.define.BUILD_ALL = "OFF"
  cmake.define.OP_<op> = "ON"
  cmake.define.<SLUG>_BUILD_TESTING = "OFF"
  
  [[tool.scikit-build.overrides]]
  if.state = "editable"
  build-dir = "build/editable"

  The root CMakeLists.txt no longer returns early for SKBUILD. Dist-info is written only for non-wheel builds, because scikit-build-core supplies its own.
• Editable installs stay live and gated: the generated docs use
  pip install --no-build-isolation -Ceditable.rebuild=true -e . (after pip install scikit-build-core~=1.0.3 cmake ninja). The package re-stages enabled operators on import, at a cost of about 0.2 s per import.
  • editable.rebuild is passed on the command line, not set in pyproject.toml. With build isolation, the rebuild can't find the isolated ninja and the import fails. Passing the flag keeps a plain pip install -e . working, as a copy.
• operators/__init__.py exports every staged operator package at runtime using pkgutil, so disabling an operator needs no edit there. It also has one if TYPE_CHECKING: import per operator (from .<op> import <Op> as <Op>), so mypy, pyright and IDEs resolve the exports.
• create and the post-gen hook point at operators/ and operators/<op>/<op>.py.
• cpp and cpp python output is unchanged apart from the CLI version pin.

Verification

• Unit tests: 768 passed, 1 skipped. A new check configures with -DOP_my_mod_op=OFF and asserts nothing is staged. Pre-commit passes on changed files.
• Generated cpp and cpp python Modules with main and with this branch, then diffed: identical apart from the holoscan-cli== pin.
• --language python Module in holoscan:v5.0.0-cuda13 (no GPU, stub libcuda), using a CLI wheel built from this branch:

Step	Result
build and run --local	Run printed received 10 samples; staged operators/my_module_op/
test --local	CTest passed
install --dev --local	from holoscan.my_module.operators import MyModuleOp worked
package --pkg-generator WHEEL	py3-none-any wheel with operators/my_module_op/{__init__,my_module_op}.py and no metadata.json
pip wheel . -Ccmake.define.OP_my_module_op=OFF	Wheel contained only operators/__init__.py
Fresh venv: install the wheel, pip check, pytest tests/python	3 tests passed
mypy / pyright on from holoscan_my_module.operators import MyModuleOp	No errors; resolves to MyModuleOp
Documented editable install, then edit my_module_op.py	Edit visible on next import; 3 tests passed
Same, with -Ccmake.define.OP_my_module_op=OFF	Operator not exported
Plain pip install -e .	3 tests passed
ruff check / ruff format --check on the generated Module	Clean

wyli also ran a GPU end-to-end check at 8bfa3d1 for both cpp python and --language python Modules; see his review comment.

Link to Devin session: https://nvidia-cloud.devinenterprise.com/sessions/e2d0e9d75b0b42f295b43491ae274a9d
Open in Devin Desktop: https://nvidia-cloud.devinenterprise.com/desktop/session/e2d0e9d75b0b42f295b43491ae274a9d?variant=devin

[devin-ai-integration]

I'll fix CI failures and address comments from users with write access. I'll skip comments containing "(aside)".

• Disable automatic comment, CI, and merge conflict monitoring

[copy-pr-bot]

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[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

None

[wyli]

Checked at 8bfa3d1. Unit tests pass, and an end-to-end run on a GPU host with holoscan:v5.0.0-cuda13 passed for both a cpp python and a --language python Module: create, build, run, CTest, install --dev, the WHEEL package, and the wheel consumer. Locally, the staging, the install component, the wheel contents, OP_<op>=OFF, and restaging after adding, renaming, or deleting an operator all behave as described.

One fix is needed before merge; see the inline comment. Type checkers no longer see the operators.