fitzyracing-fs (PyFilesystem2)

Part of 360 Bench, tested fixes for abandoned PyPI packages.

Python's Filesystem abstraction layer.

This is a fork of fs / PyFilesystem2 by Will McGugan, Martin Larralde and the PyFilesystem2 contributors, published as a drop-in replacement that can be imported again. The upstream package has not been released since 2.4.16 (May 2022). Since setuptools 82 (February 2026) removed pkg_resources, a fresh pip install fs can no longer be imported, and the pull requests that fix it have not been merged. The import name is still fs, so no code changes are needed. All credit for the original library goes to its authors and contributors; it remains available under the same MIT license.

What's fixed in this fork

Based on upstream fs==2.4.16 (tag v2.4.16); the API and behaviour are unchanged.

• import fs works again without pkg_resources. fs depended on an unpinned setuptools and called pkg_resources at import time, so with setuptools 82+ every fresh install failed with ModuleNotFoundError: No module named 'pkg_resources', on every Python version (older setuptools versions printed a UserWarning: pkg_resources is deprecated as an API instead). This fork:

  • declares fs and fs.opener as namespace packages with the standard library's pkgutil.extend_path instead of pkg_resources.declare_namespace, so extensions that add modules under fs.* / fs.opener.* (fs.sshfs, fs.smbfs, fs.dropboxfs, ...) are still found, even when they are installed in a different sys.path entry. (One edge case: a development checkout of an old extension that ships its own pkg_resources-style fs/__init__.py must not come before the fork on sys.path, or that file runs instead of the fork's. Wheels of the extensions listed above don't ship such a file.);
  • discovers opener plugins registered under the fs.opener entry point group (fs-s3fs, fs.sshfs, ...) with importlib.metadata instead of pkg_resources.iter_entry_points. It keeps the same semantics: plugins appear in registry.protocols, the first matching entry point wins, and the same EntryPointError messages are raised for broken plugins;
  • no longer depends on setuptools at all.

  Upstream issues: #577, #597; unmerged PRs: #589, #590, both by @eli-schwartz. The namespace change is #590 as proposed. The entry-point change follows #589 with one correction: on Python 3.10+, #589 as written calls entry_points(group=..., name=None), which matches no entry points. As a result registry.protocols silently lost every plugin protocol (opening a plugin URL still worked). The fork's tests cover that case with a dummy plugin.

• Packaging: pyproject.toml replaces setup.py; Python 3.9+ (Python 2.7 and 3.5 to 3.8 are no longer supported. If you are stuck on those, keep upstream fs==2.4.16 with setuptools<82).

Not included: the changes on upstream master that were merged after 2.4.16 but never released (new Walker glob filters, a reworked copy/move that raises new errors). They change behaviour, so they don't belong in a patch release that is meant to be a drop-in replacement.

Install

pip install fitzyracing-fs

Switching from fs

This distribution installs the same fs import package as the original, so your code keeps doing import fs / from fs import open_fs. Uninstall the original first, then install the fork:

pip uninstall -y fs
pip install fitzyracing-fs

The order matters. Both distributions own the same files, so if you install the fork first and uninstall fs afterwards, pip deletes the shared fs/ files and the import breaks. If that happens, run pip install --force-reinstall --no-deps fitzyracing-fs.

In requirements.txt / pyproject.toml, replace fs with fitzyracing-fs.

If you get fs through another package

pip has no equivalent of npm's overrides: it cannot replace a dependency with a differently named package. If one of your dependencies requires fs (fs-s3fs, fs.sshfs and others do), pip will keep installing the original. So you install the fork alongside it, and since both provide the same fs import name you then have to remove the original:

pip install fitzyracing-fs
pip uninstall -y fs
pip install --force-reinstall --no-deps fitzyracing-fs   # restore the files the uninstall removed

Afterwards pip check reports <package> requires fs, which is not installed; that is expected. Any later pip install/--upgrade that pulls fs back in will overwrite the fork's files, so repeat the steps above after upgrading the package that depends on it. If you can't switch, the other workaround is to pin setuptools<82 in that environment.

uv users can do this properly with an override that drops the original:

# pyproject.toml
[project]
dependencies = ["fitzyracing-fs", "...the package that depends on fs..."]

[tool.uv]
override-dependencies = ["fs; sys_platform == 'never'"]

(or uv pip install --override overrides.txt ... with that same line in overrides.txt).

Extensions that use pkg_resources themselves

Some extensions call pkg_resources in their own code. fs.sshfs 1.0.2 and fs.smbfs 1.0.7, for example, read their version with pkg_resources.resource_string. They fail to import without setuptools < 82 no matter which fs you use. With this fork, open_fs("ssh://...") then raises a clear EntryPointError: could not load entry point; No module named 'pkg_resources'. Extensions that don't use it, such as fs-s3fs, work as before.

Documentation

• Wiki
• API Documentation
• GitHub Repository
• Blog

Introduction

Think of PyFilesystem's FS objects as the next logical step to Python's file objects. In the same way that file objects abstract a single file, FS objects abstract an entire filesystem.

Let's look at a simple piece of code as an example. The following function uses the PyFilesystem API to count the number of non-blank lines of Python code in a directory. It works recursively, so it will find .py files in all sub-directories.

def count_python_loc(fs):
    """Count non-blank lines of Python code."""
    count = 0
    for path in fs.walk.files(filter=['*.py']):
        with fs.open(path) as python_file:
            count += sum(1 for line in python_file if line.strip())
    return count

We can call count_python_loc as follows:

from fs import open_fs
projects_fs = open_fs('~/projects')
print(count_python_loc(projects_fs))

The line project_fs = open_fs('~/projects') opens an FS object that maps to the projects directory in your home folder. That object is used by count_python_loc when counting lines of code.

To count the lines of Python code in a zip file, we can make the following change:

projects_fs = open_fs('zip://projects.zip')

Or to count the Python lines on an FTP server:

projects_fs = open_fs('ftp://ftp.example.org/projects')

No changes to count_python_loc are necessary, because PyFileystem provides a simple consistent interface to anything that resembles a collection of files and directories. Essentially, it allows you to write code that is independent of where and how the files are physically stored.

Contrast that with a version that purely uses the standard library:

def count_py_loc(path):
    count = 0
    for root, dirs, files in os.walk(path):
        for name in files:
            if name.endswith('.py'):
                with open(os.path.join(root, name), 'rt') as python_file:
                    count += sum(1 for line in python_file if line.strip())
    return count

This version is similar to the PyFilesystem code above, but would only work with the OS filesystem. Any other filesystem would require an entirely different API, and you would likely have to re-implement the directory walking functionality of os.walk.

Credits

This fork contains no new functionality; it exists only to keep PyFilesystem2 installable. The pkg_resources replacement is based on @eli-schwartz's upstream PRs #589 and #590. Fork maintained by Joshua Almeida.

The following developers have contributed code and their time to this projects:

• Will McGugan
• Martin Larralde
• Giampaolo Cimino
• Geoff Jukes

See CONTRIBUTORS.md for a full list of contributors.

PyFilesystem2 owes a massive debt of gratitude to the following developers who contributed code and ideas to the original version.

• Ryan Kelly
• Andrew Scheller
• Ben Timby

Apologies if I missed anyone, feel free to prompt me if your name is missing here.

Support

Problems specific to this fork (installation, pkg_resources): please use the fork's issue tracker.

If commercial support is required, please contact Will McGugan (this refers to the original project, not to the fork).

Security contact

To report a security vulnerability in this fork, please use GitHub private vulnerability reporting rather than a public issue.

License

MIT - Copyright (c) 2017-2021 The PyFilesystem2 contributors, Copyright (c) 2016-2019 Will McGugan. The original license and copyright notice are retained unchanged; fork changes are released under the same license.

Original project: https://github.com/PyFilesystem/pyfilesystem2