This branch commit refactors the pvcnoded component to better adhere to
good programming practices. The previous Daemon.py was a massive file
which contained almost 2000 lines of direct, root-level code which was
directly imported. Not only was this poor practice, but this resulted
in a nigh-unmaintainable file which was hard even for me to understand.
This refactoring splits a large section of the code from Daemon.py into
separate small modules and functions in the `util/` directory. This will
hopefully make most of the functionality easy to find and modify without
having to dig through a single large file.
Further the existing subcomponents have been moved to the `objects/`
directory which clearly separates them.
Finally, the Daemon.py code has mostly been moved into a function,
`entrypoint()`, which is then called from the `pvcnoded.py` stub.
An additional item is that most format strings have been replaced by
f-strings to make use of the Python 3.6 features in Daemon.py and the
utility files.
This should be managed in ceph.conf with the `rbd default
features` configuration option instead, and thus can be tailored to the
underlying OS version.
If this isn't, the resize will be interpreted as a MB value and result
in an absurdly big volume instead. This is the same consistency
validation that occurs on add.
Convert from human to bytes, then to megabytes and always pass this to
the RBD command. This ensures consistency regardless of what is actually
passed by the user.
Before, "-y"/"--yes" only confirmed the reboot portion. Instead, modify
this to confirm both the diff portion and the restart portion, and add
separate flags to bypass one or the other independently, ensuring the
administrator has lots of flexibility. UNSAFE mode implies "-y" so both
would be auto-confirmed if that option is set.
We need to do a bit more finagling with the logger on termination to
ensure that all messages are written and the queue drained before
actually terminating.
Joshua Boniface