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2.0.0

Removed

The following were deprecated and have been removed.

  • DeviceTree.get_devices_by_serial (use a list comprehension)

    For example, this:

    devs = devicetree.get_devices_by_serial(serial)

    could be accomplished like this:

    devs = [d for d in devicetree.devices if d.serial == serial]

  • DeviceTree.get_devices_by_type (use a list comprehension)

  • DeviceTree.get_devices_by_instance (use a list comprehension)

  • BTRFSVolumeDevice.create_subvolumes

  • MDRaidArrayDevice.devices (use MDRaidArrayDevice.members)

  • MDBiosRaidArrayDevice.devices (use MDBiosRaidArrayDevice.members)

Moved

  • DeviceTree.register_action (use DeviceTree.actions.add)
  • DeviceTree.cancel_action (use DeviceTree.actions.remove)
  • DeviceTree.find_actions (use DeviceTree.actions.find)
  • DeviceTree.prune_actions (use DeviceTree.actions.prune)
  • DeviceTree.sort_actions (use DeviceTree.actions.sort)
  • DeviceTree.process_actions (use DeviceTree.actions.process)
  • DeviceTree.get_children (use Device.children)

API Stability

A complete public API specification can be found in the documentation, which is available in the source tree at doc/api.rst and doc/api/.

Beginning with version 2.0.0 the blivet project will be using semantic versioning -- actually, we will be using a variation developed by the OpenStack project which incorporates support for Python PEP440: http://docs.openstack.org/developer/pbr/semver.html

LUKS resize

Blivet now supports resize of block devices encrypted using LUKS, including the Blivet.resize_device method.

Handling of external storage events

Blivet now has the ability to listen for uevents on block devices and adjust to externally-initiated changes. Event handling is not enabled by default. For an example of how to enable this feature, see examples/uevents.py. Most of the code related to event handling is in the new blivet.events package. The main pieces are blivet.events.manager.event_manager (an instance of blivet.events.manager.UdevEventManager), blivet.events.manager.Event, and blivet.events.handler.EventHandlerMixin (a mixin class that augments DeviceTree).

A single class for all LVs

In order to be better prepared for supporting things like lvconvert, Blivet now represents all LVs with a single class (keeping the name LVMLogicalVolumeDevice).

Using the class

In order to create LVs of various types, different values of the seg_type parameter need to be passed. For example, to create a thin pool, thin-pool segment type needs to be specified (optionally together with the thin-pool-specific parameters like metadata_size) . The same applies to thin LVs and the thin segment type. To create a snapshot LV, one needs to specify the origin LV or set the vorigin flag to True. Internal LVs require parent_lv and int_type specifying the type of the internal LV.

To determine the type of some LV, the newly added is_thin_lv, is_thin_pool, is_snapshot_lv and is_internal_lv properties can be used.

Implementation details

To avoid having a single gigantic class with hundreds of lines of code, the LVMLogicalVolumeDevice class makes use of iheritance and "merges" together the LVMLogicalVolumeBase class and mixins for specific types of LVs (thin pool, thin LV,...) adding the type-specific methods and properties as well as type-specific implementations of various methods. The @type_specific decorator makes sure that the right implementation of a method is called whenever there is a type-specific one (for example thin pools are created in a different way than good old linear LVs).

The code that is common to all LVs lives in the LVMLogicalVolumeBase class together with properties that are required by this code. Type-specific code lives in the particular mixin classes and the generic/fallback implementations live in the (ultimate) LVMLogicalVolumeDevice class' methods decorated with the @type_specific decorator.

Devices know their children

Instances of blivet.device.Device now have a list of their direct descendants: Device.children. Accordingly, DeviceTree.get_children has been removed.

Thread safety

Blivet now uses a global reentrant lock to ensure thread-safety within the Blivet, DeviceTree, Device, and DeviceFormat classes.

LVM RAID

Blivet now recognizes and supports creation of new non-linear LVs. The segment type is properly reported in the seg_type attribute of the LVMLogicalVolumeDevice objects and the seg_type constructor parameter can be used to create new LVs with specific segment types. Please note that only the linear (default), striped, mirror and raidX segment types are supported so far. Also the LVMLogicalVolumeDevice class now inherits from the RaidDevice mixin.

Added properties:

  • LVMLogicalVolumeDevice
    • is_raid_lv, mirrored
    • data_vg_space_used, metadata_vg_space_used - space used by the data/metadata part of the LV in its VG taking the RAID level (i.e. the number of mirrors) into account
  • LVMPhysicalVolume
    • free - free space in the PV (for all existing and non-existing PVs)

Removed properties:

  • LVMLogicalVolumeDevice
    • copies

Revamped code to populate the device tree

blivet.populator.Populator has been rewritten to improve maintainability. Most of the code that does type-specific handling for devices or formatting has been moved into individual helper classes under blivet.populator.helpers. The populator class itself has been rewritten as a mixin (blivet.populator.PopulatorMixin) that augments DeviceTree.

PEP8 compatibility

All code in blivet now conforms to PEP8. As a result, all non-class names in the camelCase style have been renamed to the lower_case_with_underscores style. This applies to methods within classes, but not to the names of the classes themselves -- they still use CamelCase.

Changed Size implementation

The Size class now inherits from the bytesize.Size class provided by the libbytesize library. There should be no difference in behaviour except for potential speed-up and the human_readable() method having different parameters. It now accepts the min_unit, max_places and xlate parameters described in the documentation.