abseil-py

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Are there any plans to support a flags.DEFINE_path or something similar that utilizes python's pathlib module to support declaring os.PathLike operations for the default option?

For context, I often find myself doing the following:

from absl import app, flags
from pathlib import Path

FLAGS = flags.FLAGS
flags.DEFINE_string("filepath", "path/to/some.txt", "Input filepath for program")

def main(argv_):
    # Override FLAGS.filepath with a pathlib.Path version
    FLAGS.filepath = Path(FLAGS.filepath)
    
    # Rest of program uses pathlib for path operations

if __name__ == "__main__":
    app.run(main)

It would be awesome if there was an easy way to define a Path object from the DEFINE_ definition in the first place. If adding such a feature is not feasible, I'm curious how other people are using pathlib with absl.flags as well.

Thanks!

Internally I do see one recent user contributed library that implements its own DEFINE_path for use with absl. The gist of that goes something like this (simplified for illustration purposes) in apath_flag.py library:

flags.disclaim_key_flags()  # Prevent absl from attributing flags to this module.

class _PathParser(flags.ArgumentParser):
    def parse(self, value):
        return pathlib.PurePath(value)

class _PathSerializer(flags.ArgumentSerializer):
    def serialize(self, value):
        return str(value)

def DEFINE_path(...):
    return flags.DEFINE(_PathParser(), name, default, help, flag_values,
                        _PathSerializer(), **kwargs)

I agree, it'd make sense to add something like that to absl itself as pathlib is gaining popularity.

Internal source: pyglib.contrib.gpathlib - If we do this, presumably we might just refactor it out of that.

Just wondering if there was any update on this? I'd say the pathlib library is fairly standard now so it would be nice to have support from absl if possible.

Yes this is in my queue, hopefully I can get to it after the holidays if not earlier.

Perhaps DEFINE_path can happen by these holidays? :-)