robot-python-projects

Development

Guidelines for robot Python projects — api/, robot-server/, hardware/, auth-server/, shared-data/, server-utils/, system-server/, update-server/, usb-bridge/, g-code-testing/. Use when working with Python files in these directories or their pyproject.toml files.

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Robot Python Projects

The following directories contain the robot Python projects — packages that run on or support Opentrons robots:

Project	Directory	Description
`opentrons`	`api/`	Core Opentrons Python API for protocol execution
`robot-server`	`robot-server/`	HTTP API server that runs on the robot
`opentrons-hardware`	`hardware/`	Low-level hardware control and CAN bus communication
`auth-server`	`auth-server/`	Authentication server for Flex
`opentrons-shared-data`	`shared-data/`	Shared data definitions (labware, pipettes, modules)
`server-utils`	`server-utils/`	Common utilities for Python servers
`system-server`	`system-server/`	System-level server for robot management
`otupdate`	`update-server/`	Server for software and firmware updates
`ot3usb`	`usb-bridge/`	USB bridge daemon for Flex
`g-code-testing`	`g-code-testing/`	G-code testing and emulation tools

Common Patterns

Build system: pyproject.toml with hatchling (hatchling==1.27.0)
Dependency management: uv with uv.lock files (not pipenv or poetry)
Python version: 3.12 (set via UV_PYTHON = 3.12 in scripts/python-uv.mk)
Testing: pytest 9+ with config in [tool.pytest] section of pyproject.toml
Linting: ruff (replaces flake8 + isort) with config in [tool.ruff] sections of pyproject.toml
Type checking: mypy with config in [tool.mypy] section of pyproject.toml (not mypy.ini)
Shared Make includes: all Makefiles include ../scripts/python-uv.mk which provides common targets

Running Tests

Prefer running tests scoped to the project where your changes are:

# From the project directory
cd api && make test

# Or from the monorepo root
make -C api test

Each project has a Makefile with a test target. The exception is shared-data, which uses test-py:

make -C shared-data test-py

Checking Types and Linting

Each project has a Makefile with a lint target (runs ruff check + mypy). shared-data uses lint-py:

make -C api lint
make -C shared-data lint-py

Formatting

Each project has a Makefile with a format target (runs ruff format + isort fix). shared-data uses format-py:

make -C api format
make -C shared-data format-py

Setup and Teardown

Each project has setup and teardown targets. Setup runs uv sync --frozen --group dev --python 3.12. shared-data uses setup-py and teardown-py:

make -C api setup
make -C shared-data setup-py

Or from the monorepo root for all robot Python projects at once:

make setup-py      # setup all
make teardown-py   # teardown all

Dependency Management

cd api  # or any robot Python project

uv add <package>              # add production dependency
uv add --group dev <package>  # add dev dependency
uv remove <package>           # remove dependency
uv lock                       # re-resolve after manual pyproject.toml edits

After changing dependencies, commit both pyproject.toml and uv.lock.