python new workflow with pyproject.toml with poetry

Newer python development workflow use pyproject.toml. To get started let's install poetry. 

 pip install poetry

Then we create a project with the modern project settings. 

poetry new my-python-app

And it creates this 

my-python-app/

├── pyproject.toml

├── README.md

├── src/my-python-app           # Source code

│   └── __init__.py

├── tests/            # Tests (Automatically created!)

│   └── __init__.py

And to add dependencies, run the followings

poetry add --group dev pytest pytest-cov

To run tests

poetry run pytest

To package your app, run 

poetry build

To remove dependencies

poetry remove --group dev pytest

To create a different group, we can use 

poetry add --group linting black flake8

And then run black to format your python code

poetry run black src

To install specific dependencies

# Install main + dev + linting

poetry install --with linting

# Install ONLY main (no dev, no linting)

poetry install --only main

To verifying your projects 

# Show all installed packages

poetry show

# Show only dev dependencies

poetry show --with dev

# Check dependency tree

poetry show --tree