unearth

A utility to fetch and download python packages

Why this project?

This project exists as the last piece to complete the puzzle of a package manager. The other pieces are:

resolvelib - Resolves concrete dependencies from a set of (abstract) requirements.
unearth (This project) - Finds and downloads the best match(es) for a given requirement.
build - Builds wheels from the source code.
installer - Installs packages from wheels.

They provide all the low-level functionalities that are needed to resolve and install packages.

Why not pip?

The core functionality is basically extracted from pip. However, pip is not designed to be used as a library and hence the API is not very stable. Unearth serves as a stable replacement for pip's PackageFinder API. It will follow the conventions of Semantic Versioning so that downstream projects can use it to develop their own package finding and downloading.

Requirements

unearth requires Python >=3.8

Installation

$ python -m pip install --upgrade unearth

Quickstart

Get the best matching candidate for a requirement:

>>> from unearth import PackageFinder
>>> finder = PackageFinder(index_urls=["https://pypi.org/simple/"])
>>> result = finder.find_best_match("flask>=2")
>>> result.best
Package(name='flask', version='2.1.2')

Using the CLI:

$ unearth "flask>=2"
{
  "name": "flask",
  "version": "3.0.0",
  "link": {
    "url": "https://files.pythonhosted.org/packages/36/42/015c23096649b908c809c69388a805a571a3bea44362fe87e33fc3afa01f/flask-3.0.0-py3-none-any.whl",
    "comes_from": "https://pypi.org/simple/flask/",
    "yank_reason": null,
    "requires_python": ">=3.8",
    "metadata": "https://files.pythonhosted.org/packages/36/42/015c23096649b908c809c69388a805a571a3bea44362fe87e33fc3afa01f/flask-3.0.0-py3-none-any.whl.metadata"
  }
}