Deprecate allowed_direct_url_schemes and nova.image.download.modules

The only in-tree implementation of the nova.image.download.modules
extension point was nova.image.download.file which was removed in
Pike: I7687cc89545a7a8b295dd6535b4ccebc913a2e0e

At the time of that removal, there was an operators ML thread
asking if anyone was using this code, or the extension point,
and the answer was no (or no answer at all).

Since we have no in-tree implementation of this extension point
and the extension point itself is not maintained or documented,
and even the TransferBase base class was removed in Pike, we
should deprecate the extension point and the configuration option
associated with its use so that we can simplify our internal
glance API client code.

Note that the libvirt Rbd image backend which does support
direct_url / image locations configuration for fast clones is
still supported and unrelated to this code.

Change-Id: I13162ebc9050dd2c468d0f8b969b96409f60afa8
This commit is contained in:
Matt Riedemann 2017-10-06 12:49:33 -04:00
parent f1317c016c
commit dd4ebfad13
3 changed files with 30 additions and 0 deletions

View File

@ -47,6 +47,14 @@ an image to / from glance. 0 means no retries.
"""),
cfg.ListOpt('allowed_direct_url_schemes',
default=[],
deprecated_for_removal=True,
deprecated_since='17.0.0',
deprecated_reason="""
This was originally added for the 'nova.image.download.file' FileTransfer
extension which was removed in the 16.0.0 Pike release. The
'nova.image.download.modules' extension point is not maintained
and there is no indication of its use in production clouds.
""",
help="""
List of url schemes that can be directly accessed.

View File

@ -41,4 +41,14 @@ def load_transfer_modules():
else:
module_dictionary[scheme] = mgr.driver
if module_dictionary:
LOG.warning('The nova.image.download.modules extension point is '
'deprecated for removal starting in the 17.0.0 Queens '
'release and may be removed as early as the 18.0.0 Rocky '
'release. It is not maintained and there is no indication '
'of its use in production clouds. If you are using this '
'extension point, please make the nova development team '
'aware by contacting us in the #openstack-nova freenode '
'IRC channel or on the openstack-dev mailing list.')
return module_dictionary

View File

@ -0,0 +1,12 @@
---
deprecations:
- |
The ``[glance]/allowed_direct_url_schemes`` configuration option and
``nova.image.download.modules`` extension point have been deprecated for
removal. These were originally added for the *nova.image.download.file*
FileTransfer extension which was removed in the 16.0.0 Pike release. The
``nova.image.download.modules`` extension point is not maintained
and there is no indication of its use in production clouds. If you are
using this extension point, please make the nova development team
aware by contacting us in the #openstack-nova freenode IRC channel or
on the openstack-dev mailing list.