drivers

Metador driver abstraction in order to enable different underlying implementations.

MetadorDriver module-attribute

MetadorDriver = Union[h5py.File, IH5Record]

Union of all supported classes (for static type check).

METADOR_DRIVERS module-attribute

METADOR_DRIVERS = MetadorDriverEnum.to_dict()

Dict representation of MetadorDriverEnum.

METADOR_DRIVER_CLASSES module-attribute

METADOR_DRIVER_CLASSES = tuple(METADOR_DRIVERS.values())

Tuple of all supported classes (for instance check).

MetadorDriverEnum

Bases: Enum

Supported classes that work with MetadorContainer.

Note that they must be unrelated (i.e. not subclasses of each other).

Source code in src/metador_core/container/drivers.py

class MetadorDriverEnum(Enum):
    """Supported classes that work with MetadorContainer.

    Note that they must be unrelated (i.e. not subclasses of each other).
    """

    HDF5 = h5py.File
    IH5 = IH5Record

    @classmethod
    def to_dict(cls):
        return {x: x.value for x in iter(cls)}

get_driver_type

get_driver_type(
    raw_cont: MetadorDriver,
) -> MetadorDriverEnum

Return the driver type of container (if it is a suitable (sub)class).

Source code in src/metador_core/container/drivers.py

def get_driver_type(raw_cont: MetadorDriver) -> MetadorDriverEnum:
    """Return the driver type of container (if it is a suitable (sub)class)."""
    for val, cls in METADOR_DRIVERS.items():
        if isinstance(raw_cont, cls):
            return val
    raise ValueError(f"Object not of known container driver type: {raw_cont}")

get_source

get_source(
    raw_cont: MetadorDriver,
    driver: MetadorDriverEnum = None,
) -> Any

Return an object (i.e. input resource(s)) needed to re-open the given container.

Source code in src/metador_core/container/drivers.py

def get_source(raw_cont: MetadorDriver, driver: MetadorDriverEnum = None) -> Any:
    """Return an object (i.e. input resource(s)) needed to re-open the given container."""
    c = cast(Any, raw_cont)
    driver = driver or get_driver_type(raw_cont)
    if driver == MetadorDriverEnum.HDF5:
        return c.filename
    elif driver == MetadorDriverEnum.IH5:
        return c.ih5_files

to_h5filelike

to_h5filelike(
    name_or_obj: Union[MetadorDriver, Any],
    mode: OpenMode = "r",
    *,
    driver: Optional[Type[MetadorDriver]] = None
) -> H5FileLike

Given a container or a resource with a driver, try to return a H5FileLike.

If first argument is instance of a known driver is returned unchanged. Otherwise, will try to open it using the driver (h5py.File by default).

Returns a H5FileLike compatible with MetadorContainer, or raises ValueError.

Source code in src/metador_core/container/drivers.py

def to_h5filelike(
    name_or_obj: Union[MetadorDriver, Any],
    mode: OpenMode = "r",
    *,
    # NOTE: driver takes actual class instead of enum, to also allow subclasses
    driver: Optional[Type[MetadorDriver]] = None,
) -> H5FileLike:
    """Given a container or a resource with a driver, try to return a H5FileLike.

    If first argument is instance of a known driver is returned unchanged.
    Otherwise, will try to open it using the driver (h5py.File by default).

    Returns a H5FileLike compatible with MetadorContainer, or raises ValueError.
    """
    if isinstance(name_or_obj, METADOR_DRIVER_CLASSES):
        # user has passed a h5file-like object already
        return cast(H5FileLike, name_or_obj)
    else:
        # user passed arguments to try instantiating a container object
        driver = driver or h5py.File
        if not issubclass(driver, METADOR_DRIVER_CLASSES):
            msg = f"Passed driver class not supported: {driver}"
            raise ValueError(msg)
        return cast(H5FileLike, driver(cast(Any, name_or_obj), mode))