openstack/nova
Code Issues Proposed changes

libvirt: add docstring for _get_instance_disk_info

Browse Source 
While trying to read through bug 1370590 and the call chain for lxc
there, it gets confusing trying to keep track of just what disk_info is
here - is it a dict, a json string, a list?  This is especially
confusing when you have things like
nova.virt.libvirt.blockinfo.get_disk_info used around the same code
paths and that returns a dict.

So add some docstrings in this specific method to help keep track of
what's going on here.  Long-term we should probably create some typed
objects for these things.

Related-Bug: #1370590

Change-Id: I337a8907fabfa6b0e899d45beb736a569c3067c4
This commit is contained in:
Matt Riedemann
2015-08-19 14:52:33 -07:00
parent a8949cae62
commit 0efeefe88f
1 changed files with 15 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

16
nova/virt/libvirt/driver.py
View File

@@ -6297,7 +6297,7 @@ class LibvirtDriver(driver.ComputeDriver):
instance path to use, calculated externally to handle block
migrating an instance with an old style instance path
:param disk_info:
disk info specified in _get_instance_disk_info
disk info specified in _get_instance_disk_info (list of dicts)
:param fallback_from_host:
host where we can retrieve images if the glance images are
not available.
@@ -6421,6 +6421,20 @@ class LibvirtDriver(driver.ComputeDriver):
def _get_instance_disk_info(self, instance_name, xml,
block_device_info=None):
"""Get the non-volume disk information from the domain xml
:param str instance_name: the name of the instance (domain)
:param str xml: the libvirt domain xml for the instance
:param dict block_device_info: block device info for BDMs
:returns disk_info: list of dicts with keys:
* 'type': the disk type (str)
* 'path': the disk path (str)
* 'virt_disk_size': the virtual disk size (int)
* 'backing_file': backing file of a disk image (str)
* 'disk_size': physical disk size (int)
* 'over_committed_disk_size': virt_disk_size - disk_size or 0
"""
block_device_mapping = driver.block_device_info_get_mapping(
block_device_info)