Publish a package on PyPi using Poetry

You can also read that article on my blog or on medium !

First thing first, you need Poetry if you don't have it already.

Poetry is the new standard for creating and managing virtual environment for your Python project. It is also a Python dependency management tool that is working differently as pip. It uses the new standard pyproject.toml decided by the Python Packaging Authority with PEP-518. This file merges all the previous config files that were necessary before, setup.py, requirements.txt, setup.cfg, MANIFEST.in et Pipfile, in one unique file to rule them all ! Ok, enough of Lord of the Ring.

I advise you to follow along with the documentation of poetry open.

Install Poetry

curl -sSL https://raw.githubusercontent.com/sdispater/poetry/master/get-poetry.py | python

Feel free to look here for more instructions. Updating Poetry is very easy by the way poetry update.

Create the package you want to publish on PyPi

Poetry has a nice command that can create your project tree at once poetry new <package_name>.

/<package_name>
├── README.rst # I personnaly change it to .md as I prefer writing in Markdown
├── <package_name>
│   └── __init__.py
├── pyproject.toml
└── tests
    ├── __init__.py
    └── test_package_name.py

You will need to add things to the generated pyproject.toml file, feel free to check the poetry documentation to see all the options.

[tool.poetry]
name = "vspoetry"
version = "0.1.0"
description = "Description of your package"
authors = ["MattiooFR <dugue.mathieu@gmail.com>"]
keywords = ["keyword", "another_keyword"]
readme = "README.md"
license = "MIT"
homepage = "https://github.com/MattiooFR/package_name"
repository = "https://github.com/MattiooFR/package_name"
include = [
    "LICENSE",
]

[tool.poetry.dependencies]
python = "^3.5"

[tool.poetry.dev-dependencies]

[tool.poetry.scripts]
cli_command_name = 'package_name:function'

[build-system]
requires = ["poetry>=0.12"]
build-backend = "poetry.masonry.api"

The beginning of the file is pretty straightforward. Lets focus on those three part :

• [tool.poetry.dependencies]: This is where you can list all the dependencies that your package needs to work. It's like the old requirements.txt file. You can do it by hand and then call the command poetry install to install them all for your package development and working purposes. If you use poetry add <dependency_name> (equivalent to the pip install <dependency_name>), poetry will add it there for you.
• [tool.poetry.dev-dependencies]: If you need development dependencies, that's where they go. Again, you can also install them with poetry add <dependency_name> --dev (or -D) and poetry will also put that in the right place in your pyproject.toml file.

• [tool.poetry.scripts]: This last block is very important if you want your package to have script callable from the terminal.
  

  script_name = '{package_name}:{function_name}'
  

By the way, if you still need to have a requirements.txt with all the dependencies (if you use Heroku for example), you can easily have it with this command :

poetry export -f requirements.txt > requirements.txt

Build your package

When your package is ready, simply do poetry build to create the package files

❯ poetry build
Building package_name (0.1.0)
 - Building sdist
 - Built package_name-0.1.0.tar.gz

 - Building wheel
 - Built package_name-0.1.0-py3-none-any.whl

You can test your package by doing

pip install <path_to_package_name-0.1.0-py3-none-any.whl>

If everything works, congrats ! Now lets publish it to PyPi so others can use your great package too.

Publish your package

Before publishing you should first create an account on PyPi. You can also register an account on TestPyPi if you want publishing on a test repository before trying on the official one.

Your package need to be built, so first run poetry build if you haven't done it already.

Then simply run poetry publish and your package will be publish on PyPi :

❯ poetry publish

Publishing vspoetry (0.1.0) to PyPI
Username: Mattioo
Password:
 - Uploading vspoetry-0.1.0-py3-none-any.whl 100%
 - Uploading vspoetry-0.1.0.tar.gz 100%

If you need to update your package, simply increment the version in the pyproject.toml file and use poetry publish (after you build the new package with poetry build).

Once you have done that you can then install your package :

pip install <your_package>

poetry add <your_package> # but lets be honest now you use Poetry so you would do this !

Congrats on publishing your package on PyPi and experiencing the simplicity of using a tool like Poetry.

Happy coding !

End notes

I actually just published my first package, vspoetry, while writing this tutorial. It is a package that add the vspoetry script command to my terminal and this simply add the path of the current poetry virtual environment of the project to VScode settings.json. This tells to VScode where to grab the project python venv because VScode does not do that automatically yet.