Introduction Poetry is a tool for dependency management and packaging in Python. It allows you to declare the libraries your project depends on and it will manage (install/update) them for you. Poetry offers a lockfile to ensure repeatable installs, and can build your project for distribution. System requirements Poetry requires Python 3.8+. It is multi-platform and the goal is to make it work equally well on Linux, macOS and Windows.

FAQ Why is the dependency resolution process slow? While the dependency resolver at the heart of Poetry is highly optimized and should be fast enough for most cases, with certain sets of dependencies it can take time to find a valid solution. This is due to the fact that not all libraries on PyPI have properly declared their metadata and, as such, they are not available via the PyPI JSON API.

Managing environments Poetry makes project environment isolation one of its core features. What this means is that it will always work isolated from your global Python installation. To achieve this, it will first check if it’s currently running inside a virtual environment. If it is, it will use it directly without creating a new one. But if it’s not, it will use one that it has already created or create a brand new one for you.

Dependency specification Dependencies for a project can be specified in various forms, which depend on the type of the dependency and on the optional constraints that might be needed for it to be installed. Version constraints Caret requirements Caret requirements allow SemVer compatible updates to a specified version. An update is allowed if the new version number does not modify the left-most non-zero digit in the major, minor, patch grouping. For instance, if we previously ran poetry add requests@^2.

Repositories Poetry supports the use of PyPI and private repositories for discovery of packages as well as for publishing your projects. By default, Poetry is configured to use the PyPI repository, for package installation and publishing. So, when you add dependencies to your project, Poetry will assume they are available on PyPI. This represents most cases and will likely be enough for most users. Private Repository Example Installing from private package sources By default, Poetry discovers and installs packages from PyPI.

Community Badge For any projects using Poetry, you may add its official badge somewhere prominent like the README. Markdown [](https://python-poetry.org/) reStructuredText .. image:: https://img.shields.io/endpoint?url=https://python-poetry.org/badge/v0.json :alt: Poetry :target: https://python-poetry.

FAQ Why is the dependency resolution process slow? While the dependency resolver at the heart of Poetry is highly optimized and should be fast enough for most cases, with certain sets of dependencies it can take time to find a valid solution. This is due to the fact that not all libraries on PyPI have properly declared their metadata and, as such, they are not available via the PyPI JSON API.

Commands You’ve already learned how to use the command-line interface to do some things. This chapter documents all the available commands. To get help from the command-line, simply call poetry to see the complete list of commands, then --help combined with any of those can give you more information. Global options --verbose (-v|vv|vvv): Increase the verbosity of messages: “-v” for normal output, “-vv” for more verbose output and “-vvv” for debug.

pre-commit hooks pre-commit is a framework for building and running git hooks. See the official documentation for more information: pre-commit.com This document provides a list of available pre-commit hooks provided by Poetry. Note If you specify the args: for a hook in your .pre-commit-config.yaml, the defaults are overwritten. You must fully specify all arguments for your hook if you make use of args:. Note If the pyproject.toml file is not in the root directory, you can specify args: ["-C", ".

Basic usage For the basic usage introduction we will be installing pendulum, a datetime library. If you have not yet installed Poetry, refer to the Introduction chapter. Project setup First, let’s create our new project, let’s call it poetry-demo: poetry new poetry-demo This will create the poetry-demo directory with the following content: poetry-demo ├── pyproject.toml ├── README.md ├── poetry_demo │ └── __init__.py └── tests └── __init__.py The pyproject.toml file is what is the most important here.