Skip to content

AnyPath Polymorphic Class

cloudpathlib implements a special AnyPath polymorphic class. This class will automatically instantiate a cloud path instance or a pathlib.Path instance appropriately from your input. It's also a virtual superclass of CloudPath and Path, so isinstance and issubclass checks will work in the expected way.

This functionality can be handy for situations when you want to support both local filepaths and cloud storage filepaths. If you use AnyPath, your code can switch between them seamlessly based on the contents of provided filepaths without the need of any if-else conditional blocks.

Example

from cloudpathlib import AnyPath

path = AnyPath("mydir/myfile.txt")
path
#> PosixPath('mydir/myfile.txt')

cloud_path = AnyPath("s3://mybucket/myfile.txt")
cloud_path
#> S3Path('s3://mybucket/myfile.txt')

isinstance(path, AnyPath)
#> True
isinstance(cloud_path, AnyPath)
#> True

file: URI Scheme

AnyPath also supports the file: URI scheme for paths that can be referenced with pathlib and returns a Path instance for those paths. If you need to roundtrip back to a file: URI, you can use the Path.as_uri method after any path manipulations that you do.

For example:

from cloudpathlib import AnyPath

# hostname omitted variant
path = AnyPath("file:/root/mydir/myfile.txt")
path
#> PosixPath('/root/mydir/myfile.txt')

# explicit local path variant
path = AnyPath("file:///root/mydir/myfile.txt")
path
#> PosixPath('/root/mydir/myfile.txt')

# manipulate the path and return the file:// URI
parent_uri = path.parent.as_uri()
parent_uri
#> 'file:///root/mydir'

How It Works

The constructor for AnyPath will first attempt to run the input through the CloudPath base class' constructor, which will validate the input against registered concrete CloudPath implementations. This will accept inputs that are already a cloud path class or a string with the appropriate URI scheme prefix (e.g., s3://). If no implementation validates successfully, it will then try to run the input through the Path constructor. If the Path constructor fails and raises a TypeError, then the AnyPath constructor will raise an AnyPathTypeError exception.

The virtual superclass functionality with isinstance and issubclass with the __instancecheck__ and __subclasscheck__ special methods per PEP 3119's specification.


Examples created with reprexlite