3 ms·

Show HN: Poetry – Python dependency management and packaging made easy

7 points by sdispater 9y ago

sdispater 9y ago
Poetry is a new tool to help you manage your Python projects. It is both a dependency management tool and a packaging tool. Most of the reasons why I started this are detailed in the README (along with why I don’t want to use Pipenv) here: https://github.com/sdispater/poetry#why https://github.com/sdispater/poetry#why, but if you want to know the advantages of Poetry compared to existing tools, here are a few: - Exhaustive dependency resolver - Intuitive CLI (See https://poetry.eustace.io/docs/cli/ https://poetry.eustace.io/docs/cli/) - Emphasis on semantic versioning and constraint specification so that wildcard dependencies (`*`) will be considered bad practice - Support for dependencies caret, tilde, wildcard, inequality and multiple requirements. - Only one file: the standardised pyproject.toml which aims at being readable and clear. - Mandatory compatible python versions specification. Also, Poetry is Python 3.6+ only but can manage Python 2 projects without any problem. And finally, Poetry is not completely stable yet so internally things can change but the CLI and commands are pretty much stable so backwards-incompatible changes should not happen too often.
- detaro 9y ago
  Your example of the "better" dependency resolutions seems to violate one of the constraints pipenv sees. Does pipenv somehow assume a rule that isn't there or what's going on in that example?
  - sdispater 9y ago
    Pipenv sees the wrong constraint. It just aggregates the constraint for pbr that it sees. In details: oslo.utils==1.4.0 requires: - pbr (>= 0.6, != 0.7, < 1.0) - oslo.i18n (>= 1.3) So, poetry will take the latest version of oslo.i18n which requires: - pbr (!= 2.1, >= 2.0) Poetry will detect the conflict and backtrack oslo.i18n to version 2.1.0 which requires: - pbr (>= 0.11, < 2.0) This is compatible with the requirements of oslo.utils and pbr==0.11.1 will be installed

7 points by sdispater 9y ago

Poetry is a new tool to help you manage your Python projects. It is both a dependency management tool and a packaging tool. Most of the reasons why I started this are detailed in the README (along with why I don’t want to use Pipenv) here: https://github.com/sdispater/poetry#why https://github.com/sdispater/poetry#why, but if you want to know the advantages of Poetry compared to existing tools, here are a few: - Exhaustive dependency resolver - Intuitive CLI (See https://poetry.eustace.io/docs/cli/ https://poetry.eustace.io/docs/cli/) - Emphasis on semantic versioning and constraint specification so that wildcard dependencies (`*`) will be considered bad practice - Support for dependencies caret, tilde, wildcard, inequality and multiple requirements. - Only one file: the standardised pyproject.toml which aims at being readable and clear. - Mandatory compatible python versions specification. Also, Poetry is Python 3.6+ only but can manage Python 2 projects without any problem. And finally, Poetry is not completely stable yet so internally things can change but the CLI and commands are pretty much stable so backwards-incompatible changes should not happen too often.

detaro 9y ago
Your example of the "better" dependency resolutions seems to violate one of the constraints pipenv sees. Does pipenv somehow assume a rule that isn't there or what's going on in that example?
- sdispater 9y ago
  Pipenv sees the wrong constraint. It just aggregates the constraint for pbr that it sees. In details: oslo.utils==1.4.0 requires: - pbr (>= 0.6, != 0.7, < 1.0) - oslo.i18n (>= 1.3) So, poetry will take the latest version of oslo.i18n which requires: - pbr (!= 2.1, >= 2.0) Poetry will detect the conflict and backtrack oslo.i18n to version 2.1.0 which requires: - pbr (>= 0.11, < 2.0) This is compatible with the requirements of oslo.utils and pbr==0.11.1 will be installed