"""This module implements a container that holds the path to a file as data"""
import logging
import pathlib
from typing import Union
from ..mixins import ForwardAttrsToDataMixin
from . import BaseDataContainer, is_container
log = logging.getLogger(__name__)
# -----------------------------------------------------------------------------
[docs]@is_container
class PathContainer(ForwardAttrsToDataMixin, BaseDataContainer):
"""A container that maps to a file system path.
It uses :py:class:`pathlib.Path` to represent the given path and allow
easy access and manipulation.
To have direct access to the underlying :py:class:`pathlib.Path` object,
use the :py:meth:`.fs_path` property.
.. note::
The paths can also be paths to directories. However, it's worth
considering using a :py:class:`~dantro.groups.dirpath.DirectoryGroup`
if it is desired to carry over the directory tree structure into the
data tree.
Unlike in :py:class:`~dantro.groups.dirpath.DirectoryGroup`, the local
file system path is set via the ``data`` argument during initialization
and not via a data attribute.
"""
[docs] def __init__(
self,
*args,
name: str,
data: Union[str, pathlib.Path] = None,
parent: "DirectoryGroup" = None,
**kwargs,
):
"""Sets up a container that holds a filesystem path as data.
.. note::
The filesystem path need not necessarily exist and it also need
not be equivalent to the path within the data tree.
Args:
*args: Passed to parent class init
name (str): The name of this container
data (Union[str, pathlib.Path], optional): The filesystem path
this object is meant to represent. Can be empty if this
container is initialized from a ``parent`` directory group, in
which case the information stored therein and the ``name`` of
this container will be used to generate the path.
parent (DirectoryGroup, optional): If ``data`` was not given, the
path of this parent group and the ``name`` of this container
will be used to generate a path.
**kwargs: Passed to parent class init
"""
from ..groups import DirectoryGroup
if data is None:
if parent is not None and isinstance(parent, DirectoryGroup):
data = parent.fs_path.joinpath(name)
else:
raise TypeError(
f"If not supplying `data` argument to {self.classname} "
f"'{name}', need a parent that is a DirectoryGroup and "
"that can be used to deduce a path. "
f"Parent was: {parent}"
)
data = pathlib.Path(data)
super().__init__(*args, name=name, data=data, parent=parent, **kwargs)
@property
def fs_path(self) -> pathlib.Path:
"""Returns the filesystem path associated with this container.
This property is identical to the ``data`` property.
"""
return self.data
def __delitem__(self, key):
raise NotImplementedError("Cannot delete path elements.")
def __setitem__(self, key, value):
raise NotImplementedError("Cannot set path elements.")
def __getitem__(self, key):
raise NotImplementedError("Cannot get path elements.")
