When #152 is merged, user subclasses that override upath.core._FSSpecAccessor will very likely not work correctly with Python3.12, because the 3.12 implementation doesn't use the accessor.
There should be a recommended way for users to subclass UPath for Python3.12 AND Python3.8-Python3.11 without having to maintain two code paths.
Searching GitHub, I could collect an example set of user subclasses that can be split into ~3~ 4 intended use cases:
(1) customize fsspec filesystem creation
here the user wants to change the way the fsspec filesystem instance is created:
upath.UPath should offer a classmethod _make_fs() (?) to allow fsspec filesystem instance customization.
It should be possible too to support old code on python3.12 by detecting when the _default_accessor attribute is present and use that to make a compatible _make_fs() (?) fallback method.
(2) customize path formatting
here the user wants to change the way the path is formatted. Examples:
Not really specific to the Accessor subclassing, because the implementation is overriding __new__ in the UPath subclass. The intention is to extract additional fsspec storage_options from the provided args when instantiating UPath(). Example:
While this list in not complete, it does cover ~3~ 4 reasonably easy to solve cases for making the transition to 3.12 less bumpy for custom subclasses.
[x] (ALL) detect custom _accessor in py3.12 classes and provide warning with instructions on how to migrate.
[x] (1) provide customizable fsspec filesystem factory classmethod
[ ] (2) provide instructions for how to migrate to .path (with potential customization)
When #152 is merged, user subclasses that override
upath.core._FSSpecAccessorwill very likely not work correctly with Python3.12, because the 3.12 implementation doesn't use the accessor.There should be a recommended way for users to subclass
UPathfor Python3.12 AND Python3.8-Python3.11 without having to maintain two code paths.Searching GitHub, I could collect an example set of user subclasses that can be split into ~3~ 4 intended use cases:
(1) customize fsspec filesystem creation
here the user wants to change the way the fsspec filesystem instance is created:
upath.UPathshould offer a classmethod_make_fs()(?) to allow fsspec filesystem instance customization.It should be possible too to support old code on python3.12 by detecting when the
_default_accessorattribute is present and use that to make a compatible_make_fs()(?) fallback method.(2) customize path formatting
here the user wants to change the way the path is formatted. Examples:
(3) fix behavior of some accessor methods
here the behavior of a fsspec filesystem method is fixed by fixing the accessor method. Example:
boxfs.mkdir: https://github.com/IBM/boxfs/blob/718fb0071d20a7004f44fe2fa0eac26dc9c3d5d5/src/boxfs/_upath.py#L4-L12(4) customize storage_options extraction
Not really specific to the Accessor subclassing, because the implementation is overriding
__new__in the UPath subclass. The intention is to extract additional fsspec storage_options from the provided args when instantiatingUPath(). Example:ObjectStoragePathextracts a connection id from the urlpath: https://github.com/apache/airflow/blob/07fd3646fa765859a152731bf135ea944d0753d7/airflow/io/path.py#L96-L153TODO
While this list in not complete, it does cover ~3~ 4 reasonably easy to solve cases for making the transition to 3.12 less bumpy for custom subclasses.
_accessorinpy3.12classes and provide warning with instructions on how to migrate..path(with potential customization)UPath.mkdir, etc... directly.