Metadata hook plugins

---

Metadata hooks allow for the modification of project metadata after it has been loaded.

Known third-party

• hatch-docstring-description - set the project description using docstrings
• hatch-fancy-pypi-readme - dynamically construct the README
• hatch-nodejs-version - uses fields from NodeJS package.json files
• hatch-odoo - determine dependencies based on manifests of Odoo add-ons
• hatch-requirements-txt - read project dependencies from requirements.txt files

MetadataHookInterface

Example usage:

plugin.py hooks.py

from hatchling.metadata.plugin.interface import MetadataHookInterface


class SpecialMetadataHook(MetadataHookInterface):
    PLUGIN_NAME = 'special'
    ...

from hatchling.plugin import hookimpl

from .plugin import SpecialMetadataHook


@hookimpl
def hatch_register_metadata_hook():
    return SpecialMetadataHook

Source code in backend/src/hatchling/metadata/plugin/interface.py

class MetadataHookInterface(ABC):  # no cov
    """
    Example usage:

    ```python tab="plugin.py"
    from hatchling.metadata.plugin.interface import MetadataHookInterface


    class SpecialMetadataHook(MetadataHookInterface):
        PLUGIN_NAME = 'special'
        ...
    ```

    ```python tab="hooks.py"
    from hatchling.plugin import hookimpl

    from .plugin import SpecialMetadataHook


    @hookimpl
    def hatch_register_metadata_hook():
        return SpecialMetadataHook
    ```
    """

    PLUGIN_NAME = ''
    """The name used for selection."""

    def __init__(self, root: str, config: dict) -> None:
        self.__root = root
        self.__config = config

    @property
    def root(self) -> str:
        """
        The root of the project tree.
        """
        return self.__root

    @property
    def config(self) -> dict:
        """
        The hook configuration.

        ```toml config-example
        [tool.hatch.metadata.hooks.<PLUGIN_NAME>]
        ```
        """
        return self.__config

    @abstractmethod
    def update(self, metadata: dict) -> None:
        """
        This updates the metadata mapping of the `project` table in-place.
        """

    def get_known_classifiers(self) -> list[str]:  # noqa: PLR6301
        """
        This returns extra classifiers that should be considered valid in addition to the ones known to PyPI.
        """
        return []

PLUGIN_NAME = '' class-attribute instance-attribute

The name used for selection.

root: str property

The root of the project tree.

config: dict property

The hook configuration.

pyproject.toml hatch.toml

[tool.hatch.metadata.hooks.<PLUGIN_NAME>]

[metadata.hooks.<PLUGIN_NAME>]

update(metadata: dict) -> None abstractmethod

This updates the metadata mapping of the project table in-place.

Source code in backend/src/hatchling/metadata/plugin/interface.py

@abstractmethod
def update(self, metadata: dict) -> None:
    """
    This updates the metadata mapping of the `project` table in-place.
    """

get_known_classifiers() -> list[str]

This returns extra classifiers that should be considered valid in addition to the ones known to PyPI.

Source code in backend/src/hatchling/metadata/plugin/interface.py

def get_known_classifiers(self) -> list[str]:  # noqa: PLR6301
    """
    This returns extra classifiers that should be considered valid in addition to the ones known to PyPI.
    """
    return []