python-project-setup

Python Project Setup

Instructions

Step 1: Gather Requirements

Ask:

1. What type of project? (library/package, web app, CLI tool, data pipeline)
2. Minimum Python version? (default: 3.11+)
3. Package manager preference? (pip, uv, poetry, pdm)
4. Layout preference? (src-layout or flat-layout)
5. What frameworks? (FastAPI, Django, Flask, Click, Typer)
6. CI platform? (GitHub Actions, GitLab CI)

Step 2: Project Structure

src-layout (recommended for libraries):

my-project/
  src/
    my_package/
      __init__.py
      main.py
      models.py
  tests/
    __init__.py
    conftest.py
    test_main.py
  pyproject.toml
  README.md
  .pre-commit-config.yaml
  .github/
    workflows/
      ci.yml

flat-layout (simpler, for apps):

my-project/
  my_package/
    __init__.py
    main.py
  tests/
    conftest.py
    test_main.py
  pyproject.toml
  README.md

Use src-layout by default. It prevents accidental imports of the source during testing.

Step 3: Generate pyproject.toml

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

[project]
name = "my-package"
version = "0.1.0"
description = "A brief description of the project"
readme = "README.md"
license = "MIT"
requires-python = ">=3.11"
authors = [
    { name = "Your Name", email = "[email protected]" },
]
dependencies = []

[project.optional-dependencies]
dev = [
    "pytest>=8.0",
    "pytest-cov>=5.0",
    "ruff>=0.4",
    "mypy>=1.10",
    "pre-commit>=3.7",
]

[project.scripts]
my-cli = "my_package.main:cli"

[tool.pytest.ini_options]
testpaths = ["tests"]
addopts = [
    "--strict-markers",
    "--strict-config",
    "-ra",
]

[tool.ruff]
target-version = "py311"
line-length = 88

[tool.ruff.lint]
select = [
    "E",    # pycodestyle errors
    "W",    # pycodestyle warnings
    "F",    # pyflakes
    "I",    # isort
    "B",    # flake8-bugbear
    "C4",   # flake8-comprehensions
    "UP",   # pyupgrade
    "SIM",  # flake8-simplify
]

[tool.ruff.lint.isort]
known-first-party = ["my_package"]

[tool.mypy]
python_version = "3.11"
strict = true
warn_return_any = true
warn_unused_configs = true

[tool.coverage.run]
source = ["src/my_package"]
branch = true

[tool.coverage.report]
fail_under = 80
show_missing = true
exclude_lines = [
    "pragma: no cover",
    "if TYPE_CHECKING:",
]