Hi! After playing around a bit for a few months with a bunch of proof-of-concept level scripts to be able to debug my btrfs file systems, the inevitable happened:
https://github.com/knorrie/python-btrfs/ Currently, the primary goal of this module is to be able to inspect the internals of an existing filesystem for educational purposes. In the last week I started sorting out the puzzle pieces I already assembled, and put most of them together into a proper python library to query a btrfs filesystem. The python module acts as a wrapper around the low level kernel calls and btrfs data structures, presenting them as python objects with interesting attributes and references to other objects. Using these helpers, it should be fairly easy to reimplement the same functionality as for example btrfs fi df, btrfs fi show and btrfs inspect-internal provide. For example: import btrfs fs = btrfs.FileSystem('/') for space in fs.space_info(): print("{0}, {1}: total={2}, used={3}".format( btrfs.utils.block_group_type_str(space.flags), btrfs.utils.block_group_profile_str(space.flags), btrfs.utils.pretty_size(space.total_bytes), btrfs.utils.pretty_size(space.used_bytes))) results in: Data, single: total=15.94GiB, used=6.30GiB System, DUP: total=32.00MiB, used=16.00KiB Metadata, DUP: total=768.00MiB, used=158.72MiB GlobalReserve, single: total=64.00MiB, used=0.00B The btrfs directory in the source is the python module which is to be imported as btrfs. The examples directory contains example programs that use the library. For all functionality that's added in the lib, there must be an example program that uses it. Currently, the code can look at devices, chunks, block groups with their usage and lists of data extents. I usually write quite elaborate git commit messages, so when looking through my commits or doing a git blame on code, you should (now and later) find a nice description about the hows whys etc of the code. Why?! * Because it's fun! * Because I get sick of using horrible ducttape regex solutions to programmatically parse human readable output of external tools to implement monitoring tools~~!11one. * Because I might to be able to help other people that also want to learn the internals of btrfs. * Much more... How? * It's a python library, so the code will have a decent level of pythonicity. The ioctl search returns a generator, the search key is a nice object you can just increment etc... * This is a work in progress. I can only add support for parts of btrfs that I understand myself first. Moo! Hans van Kranenburg -- Hans van Kranenburg - System / Network Engineer T +31 (0)10 2760434 | hans.van.kranenb...@mendix.com | www.mendix.com -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
