XRootDPyFS

XRootDPyFS is a PyFilesystem interface to XRootD.

XRootD protocol aims at giving high performance, scalable fault tolerant access to data repositories of many kinds. The XRootDPyFS adds a high-level interface on top of the existing Python interface (pyxrootd) and makes it easy to e.g. copy a directory in parallel or recursively remove a directory.

Further documentation is available on https://xrootdpyfs.readthedocs.io/.

Getting started

If you just want to try out the library, the easiest is to use Docker.

Build the image:

$ docker build --platform linux/amd64 -t xrootd .

Run the container and launch xrootd:

$ docker run --platform linux/amd64 -h xrootdpyfs -it xrootd bash

You will see the logs in the stdout. Next, in another shell, connect the container and fire up an ipython shell:

$ docker ps  # find the container id
$ docker exec -it <container-id> bash
[xrootdpyfs@xrootdpyfs code]$ ipython

Quick examples

Here is a quick example of a file listing with the xrootd PyFilesystem integration:

>>> from xrootdpyfs import XRootDPyFS
>>> fs = XRootDPyFS("root://localhost//tmp/")
>>> fs.listdir("xrootdpyfs")
['test.txt']

Or, alternatively using the PyFilesystem opener (note the first import xrootdpyfs is required to ensure the XRootDPyFS opener is registered):

>>> import xrootdpyfs
>>> from fs.opener import open_fs
>>> fs = open_fs("root://localhost//tmp/")
>>> fs.listdir("xrootdpyfs")
['test.txt']

Reading files:

>>> f = fs.open("xrootdpyfs/test.txt")
>>> f.read()
b'Hello XRootD!\n'
>>> f.close()

Reading files using the readtext() method:

>>> fs.readtext("xrootdpyfs/test.txt")
b'Hello XRootD!\n'

Writing files:

>>> f = fs.open("xrootdpyfs/hello.txt", "w+")
>>> f.write("World")
>>> f.close()

Writing files using the writetext() method:

>>> fs.writetext("xrootdpyfs/test.txt", "World")

Development

The easiest way to develop is to build the Docker image and mount the source code as a volume to test any code modification with a running XRootD server:

$ docker build --platform linux/amd64 -t xrootd --progress=plain .
$ docker run --platform linux/amd64 -h xrootdpyfs -it -v <absolute path to this project>:/code xrootd bash
[xrootdpyfs@xrootdpyfs code]$ xrootd

In another shell:

$ docker ps  # find the container id
$ docker exec -it <container-id> bash
[xrootdpyfs@xrootdpyfs code]$ python -m pytest -vvv tests

If you want to test a specific version of xrootd, run:

$ docker build --platform linux/amd64 --build-arg xrootd_version=4.12.7 -t xrootd --progress=plain .

Documentation

Documentation is available at <http://xrootdpyfs.readthedocs.io/> or can be build using Sphinx:

pip install Sphinx
python setup.py build_sphinx

Testing

Running the tests are most easily done using docker:

$ docker build --platform linux/amd64 -t xrootd . && docker run --platform linux/amd64 -h xrootdpyfs -it xrootd