astroclark / fuse-posix

POSIX interface to Rucio namespace

Rucio FUSE-posix interface

This repository carries the best attempt at making the Rucio namespace posix-mountable.

It is based on C code (for the custom FUSE specialization) and on C++11 for utilities and wrappers.

This tool is intended as an alpha version unless explicitly said and has to be considered WIP.

Please note that the first target is to get a read-only file system.

Access pattern

The Rucio file catalog is much flatter than that of a usual POSIX filesystems and as such its representation has to be structured according to that:

• the root of the mount is intended to be a cvmfs-like "/rucio";
• the first level of the tree (namely /rucio/*) should be filled with all the available scopes;
• each scope should appear as a directory filled with its DiDs;
• file DiDs will appear as files;
• container and dataset DiDs will appear as directories;
• datasets and containers might include already represented DiDs: a routine to handle such loops should be present.

DONEs

• Curl-REST wrapper based on libcurl has been implemented in the form of GET and POST methods, for the moment. The GET method has been tested widely and appears to be consistent with the output of the curl CLI.
• The curl-REST wrapper uses a singleton-equipped curl instance to limit memory fingerprint.
• Rucio-API wrappers, based on Rucio's RESTFul interface, are being developed. At the moment access token retrieval through userpass authentication and scopes listing are implemented and tested.

TODOs

• implement getattr, readdir and read methods
• surely a lot more...

How to build

To build the software please run:

./build.sh

This has been tested on CentOS7 and Mac OS X Mojave 10.14.6 .

To complete the build libcurl-devel, fuse-libs and fuse-devel packages (or equivalent) must be present: cmake will try to locate them for you and trigger some build messages if unable to do so. Please note that cmake version 3 or greater is needed.