project-setup-python

name	project-setup-python
version	1.19.1
license	Apache-2.0
description	Set up Python NVIDIA USD Validation plugins: entry points, custom rules, uv/pip install, first CLI run. Do NOT use for requirements.
metadata	{"author":"NVIDIA","tags":["usd-validation","python","plugin-setup"]}
compatibility	Requires Python 3.10-3.12, uv or pip, network access to Python package indexes, and Linux/macOS shell or Windows PowerShell command syntax.

Project Setup and First Validation (Python)

Purpose

usd-validation-nvidia is distributed as a Python package on PyPI. This skill shows how to scaffold a minimal plugin project and run its first validation command.

Prerequisites

• Python 3.10-3.12.
• uv or pip with package-index access.

Project Structure

my-usd-validation-plugin/
  pyproject.toml
  main.py

After uv init, create main.py and update pyproject.toml to match the structure below.

Verify Python Version

This skill requires Python 3.10-3.12. Before setup, run uv run --python 3.11 python --version or py -3.11 --version on Windows; use 3.10 or 3.12 instead if that is the supported interpreter. If no supported interpreter is available, stop with: "This skill requires Python 3.10-3.12. Install a supported interpreter, then rerun." For uv workflows, install one with uv python install 3.11.

Setup with uv (Recommended)

Start from a clean parent directory outside this workspace where my-usd-validation-plugin does not already exist. If that folder already exists, choose a different folder name or move the existing folder aside before continuing.

mkdir -p my-usd-validation-plugin && cd my-usd-validation-plugin
uv init --no-workspace --python 3.11
uv add "usd-validation-nvidia[usd]"

This creates a pyproject.toml and uv.lock. The minimal example uses:

[project]
name = "usd-validation-minimal-plugin"
version = "0.1.0"
description = "Minimal NVIDIA USD Validation plugin example"
requires-python = ">=3.10,<3.13"
dependencies = [
    "usd-validation-nvidia[usd]",
]

[project.entry-points."usd_validation_nvidia"]
minimal_example = "main:Plugin"

[build-system]
requires = ["hatchling"]
build-backend = "hatchling.build"

[tool.hatch.build.targets.wheel]
only-include = ["main.py"]

Adding optional dependencies

For NumPy acceleration:

uv add "usd-validation-nvidia[numpy]"

For profile code generation, use the public package:

uv add usd-profiles-nvidia

Setup with pip

pip install "usd-validation-nvidia[usd]"
pip install -e .

Minimal main.py

Source: examples/python/minimal/pyproject.toml

Source: examples/python/minimal/main.py snippet custom-rule

Followed by: examples/python/minimal/main.py snippet plugin-entry-point

Asset: examples/assets/asset.usda

Run

From the repository root:

uv run \
  --no-project \
  --with usd-profiles-nvidia \
  python -m usd_profiles_nvidia.codegen \
    --docs-root specs \
    --destination-dir src \
    --package-name usd_validation_nvidia.capabilities \
    --reverse-domain com.nvidia.usd

uv run \
  --with . \
  --with examples/python/minimal \
  nvidia_usd_validate --rule ExampleDefaultPrimChecker examples/assets/asset.usda

On Windows:

uv run `
  --no-project `
  --with usd-profiles-nvidia `
  python -m usd_profiles_nvidia.codegen `
    --docs-root specs `
    --destination-dir src `
    --package-name usd_validation_nvidia.capabilities `
    --reverse-domain com.nvidia.usd
uv run `
  --with . `
  --with examples/python/minimal `
  nvidia_usd_validate --rule ExampleDefaultPrimChecker examples/assets/asset.usda

Note: replace --with . with --with usd-validation-nvidia to use the public build.

Key Types / Functions

• register_rule("Example"): registers the rule in the Example category; the string argument is the rule category shown by the CLI.
• BaseRuleChecker.CheckStage(...): validates the whole stage once.
• _AddFailedCheck(...): reports a validation failure.

Key Dependencies

Package	Purpose
usd-validation-nvidia[usd]	Engine, CLI, built-in validators, and usd-core runtime dependency
usd-validation-nvidia[numpy]	Optional NumPy acceleration
usd-profiles-nvidia	Profile/capability/feature/requirement modeling and code generation package
usd-profiles-nvidia[sphinx]	Optional Sphinx directives and roles for profile documentation

Limitations

• Covers basic rule plugins only; use validate-requirements for requirement-backed workflows.
• Does not publish packages or configure external CI.

Common Pitfalls

• usd-validation-nvidia requires Python 3.10-3.12.
• Install the plugin package into the same environment as usd-validation-nvidia.
• In a fresh source checkout, generate src/usd_validation_nvidia/capabilities with uv run --no-project --with usd-profiles-nvidia python -m usd_profiles_nvidia.codegen ... before commands that install the local repo with --with ..
• Point the entry point at main:Plugin when the package exposes a Plugin class.
• Confirm the custom rule appears in nvidia_usd_validate --help before debugging validation output.
• Project-specific profiles such as Prop-Robotics-Neutral must be installed and registered before use.

Troubleshooting

• If nvidia_usd_validate --help does not list the custom rule, confirm the plugin is installed in the same environment and the entry point targets main:Plugin.
• If local source installation fails because capabilities is missing, generate src/usd_validation_nvidia/capabilities from specs/ before using --with ..