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:mod:`!importlib.resources.abc` -- Abstract base classes for resources

.. module:: importlib.resources.abc
    :synopsis: Abstract base classes for resources

Source code: :source:`Lib/importlib/resources/abc.py`

.. versionadded:: 3.11

Superseded by TraversableResources

An :term:`abstract base class` to provide the ability to read resources.

From the perspective of this ABC, a resource is a binary artifact that is shipped within a package. Typically this is something like a data file that lives next to the __init__.py file of the package. The purpose of this class is to help abstract out the accessing of such data files so that it does not matter if the package and its data file(s) are stored e.g. in a zip file versus on the file system.

For any of methods of this class, a resource argument is expected to be a :term:`path-like object` which represents conceptually just a file name. This means that no subdirectory paths should be included in the resource argument. This is because the location of the package the reader is for, acts as the "directory". Hence the metaphor for directories and file names is packages and resources, respectively. This is also why instances of this class are expected to directly correlate to a specific package (instead of potentially representing multiple packages or a module).

Loaders that wish to support resource reading are expected to provide a method called get_resource_reader(fullname) which returns an object implementing this ABC's interface. If the module specified by fullname is not a package, this method should return :const:`None`. An object compatible with this ABC should only be returned when the specified module is a package.

.. deprecated:: 3.12
   Use :class:`importlib.resources.abc.TraversableResources` instead.


.. method:: open_resource(resource)
   :abstractmethod:

   Returns an opened, :term:`file-like object` for binary reading
   of the *resource*.

   If the resource cannot be found, :exc:`FileNotFoundError` is
   raised.


.. method:: resource_path(resource)
   :abstractmethod:

   Returns the file system path to the *resource*.

   If the resource does not concretely exist on the file system,
   raise :exc:`FileNotFoundError`.


.. method:: is_resource(name)
   :abstractmethod:

   Returns ``True`` if the named *name* is considered a resource.
   :exc:`FileNotFoundError` is raised if *name* does not exist.


.. method:: contents()
   :abstractmethod:

   Returns an :term:`iterable` of strings over the contents of
   the package. Do note that it is not required that all names
   returned by the iterator be actual resources, e.g. it is
   acceptable to return names for which :meth:`is_resource` would
   be false.

   Allowing non-resource names to be returned is to allow for
   situations where how a package and its resources are stored
   are known a priori and the non-resource names would be useful.
   For instance, returning subdirectory names is allowed so that
   when it is known that the package and resources are stored on
   the file system then those subdirectory names can be used
   directly.

   The abstract method returns an iterable of no items.

An object with a subset of :class:`pathlib.Path` methods suitable for traversing directories and opening files.

For a representation of the object on the file-system, use :meth:`importlib.resources.as_file`.

.. attribute:: name

   Abstract. The base name of this object without any parent references.


.. method:: iterdir()
   :abstractmethod:

   Yield Traversable objects in self.


.. method:: is_dir()
   :abstractmethod:

   Return ``True`` if self is a directory.


.. method:: is_file()
   :abstractmethod:

   Return ``True`` if self is a file.


.. method:: joinpath(*pathsegments)
   :abstractmethod:

   Traverse directories according to *pathsegments* and return
   the result as :class:`!Traversable`.

   Each *pathsegments* argument may contain multiple names separated by
   forward slashes (``/``, ``posixpath.sep`` ).
   For example, the following are equivalent::

       files.joinpath('subdir', 'subsubdir', 'file.txt')
       files.joinpath('subdir/subsubdir/file.txt')

   Note that some :class:`!Traversable` implementations
   might not be updated to the latest version of the protocol.
   For compatibility with such implementations, provide a single argument
   without path separators to each call to ``joinpath``. For example::

       files.joinpath('subdir').joinpath('subsubdir').joinpath('file.txt')

   .. versionchanged:: 3.11

      ``joinpath`` accepts multiple *pathsegments*, and these segments
      may contain forward slashes as path separators.
      Previously, only a single *child* argument was accepted.


.. method:: __truediv__(child)
   :abstractmethod:

   Return Traversable child in self.
   Equivalent to ``joinpath(child)``.


.. method:: open(mode='r', *args, **kwargs)
   :abstractmethod:

   *mode* may be 'r' or 'rb' to open as text or binary. Return a handle
   suitable for reading (same as :attr:`pathlib.Path.open`).

   When opening as text, accepts encoding parameters such as those
   accepted by :class:`io.TextIOWrapper`.


.. method:: read_bytes()

   Read contents of self as bytes.


.. method:: read_text(encoding=None)

   Read contents of self as text.

An abstract base class for resource readers capable of serving the :meth:`importlib.resources.files` interface. Subclasses :class:`ResourceReader` and provides concrete implementations of the :class:`!ResourceReader`'s abstract methods. Therefore, any loader supplying :class:`!TraversableResources` also supplies :class:`!ResourceReader`.

Loaders that wish to support resource reading are expected to implement this interface.

.. method:: files()
   :abstractmethod:

   Returns a :class:`importlib.resources.abc.Traversable` object for the loaded
   package.