如何在Poetry管理的单仓（Monorepo）中复用pyproject.toml配置？

Great question! Managing shared configurations across a Poetry-based monorepo is a common pain point, but there are a few straightforward, maintainable ways to solve it—let’s break down the best approaches:

1. Use Poetry’s Built-In extends for Centralized Parent Configuration #

Poetry 1.2+ introduced the extends field, which lets child projects inherit configuration from a parent pyproject.toml file. This is perfect for sharing tooling settings like taskipy, isort, and black.

Step 1: Create a Root Parent Configuration #

In your monorepo root, create a pyproject.toml (it doesn’t need to be a full Poetry project—just a container for shared settings):

# monorepo/pyproject.toml
[tool.taskipy.tasks]
lint = "isort . && black . && flake8"
test = "pytest tests/"
format = "isort . --fix && black ."

[tool.isort]
profile = "black"
line_length = 88
include_trailing_comma = true
multi_line_output = 3

[tool.black]
line-length = 88
target-version = ["py310", "py311"]
include = '\.pyi?$'

# Optional: Share common dev dependencies too
[tool.poetry.group.dev.dependencies]
pytest = "^7.4.0"
isort = "^5.12.0"
black = "^23.7.0"
taskipy = "^1.13.0"
flake8 = "^6.0.0"

Step 2: Inherit from the Parent in Child Projects #

In each child project’s pyproject.toml, add the extends field to pull in the root configuration. You can also override or add project-specific settings as needed:

# monorepo/a/pyproject.toml
[tool.poetry]
name = "a"
version = "0.1.0"
authors = ["Your Name <you@example.com>"]
extends = "../pyproject.toml"  # Inherit root config

# Project-specific dependencies
[tool.poetry.dependencies]
python = "^3.10"
requests = "^2.31.0"

# Optional: Inherit shared dev dependencies + add project-specific ones
[tool.poetry.group.dev]
inherit = true  # Pull in root dev dependencies
[tool.poetry.group.dev.dependencies]
pytest-cov = "^4.1.0"  # Add a dev dep unique to project a

# Optional: Override a shared tool setting (e.g., adjust black's line length for this project)
[tool.black]
line-length = 100

2. Split Shared Configs into a Dedicated File (Alternative) #

If you prefer to keep shared tooling settings separate from the root pyproject.toml, create a standalone configuration file (e.g., common-tools.toml) and point child projects to it via extends:

# monorepo/common-tools.toml
[tool.taskipy.tasks]
lint = "isort . && black ."
test = "pytest"

[tool.isort]
profile = "black"

Then in child projects:

[tool.poetry]
extends = "../common-tools.toml"

Key Notes for Success #

• Poetry Version: Ensure you’re using Poetry 1.2.0 or newer—older versions don’t support extends or dependency group inheritance.
• Configuration Merging: Child project settings will override parent settings for any fields you redefine. For tools like taskipy, child tasks are added to the parent tasks (not replaced).
• Consistency: Run commands from the child project directory (e.g., cd a && poetry run task lint)—Poetry will resolve the inherited configuration correctly.

These methods eliminate duplicate configs, make updates easier (change once, apply everywhere), and keep your monorepo organized.

内容的提问来源于stack exchange，提问作者northtree