What migrate_instance did around the migration itself:
- It checked the destination with a 1 s TCP probe of the libvirt port,
which passes while libvirt is down or refuses the login. It now uses
the compute's connection status, as the rest of the app does.
- Two requests for the same VM waited for the compute locks one after
the other; the second then migrated with the VM's old location. The
VM's record is read again under the locks, and the request is
refused when the VM is no longer on the source.
- Restoring autostart on the destination came after the migration but
before the database move; when it failed, the VM ran on the
destination while the app recorded it on the source. Autostart is
now read from libvirt and a failure to restore it is only logged.
- A database failure after a successful migration was logged as
nothing; the log now says the VM migrated and recording it failed.
- When the destination's list had already made a record for the VM,
the merge kept the owners but dropped the template mark.
Web views:
- 34 views returned to request.META["HTTP_REFERER"] + "#tab": without
a Referer they failed with a TypeError (500), and a Referer from
another site was followed (open redirect). They return through
_back(), which keeps a same-site Referer and otherwise opens the VM
page at the tab. get_safe_redirect uses the same check. Rejected disk
options also return to the VM's disks tab instead of the VM list.
- migrate_instance returned silently when the target was the current
compute or unreachable, so the web view logged "Instance is migrated"
and the API answered "instance migrate is started". It now raises;
the view reports the error and logs only a completed migration, and
an unknown compute id is a 404 instead of a 500. The automatic
migration after a clone skips a target that is the current compute.
- add_owner and del_owner failed with a 500 without their ids, add_owner
also when the user was already an owner, and del_owner deleted the
given ownership record even when it belonged to another VM. Ids are
validated, a record of another VM is a 404, and a repeated owner is
reported.
- Broad handlers that hid programming errors are narrowed: clone catches
libvirt, value and OS errors (a lock timeout included), ownership
lookups catch DoesNotExist. The DRBD status no longer needs its bare
except: the VM name is escaped in the regex, which was the only thing
that could fail there.
API:
- A libvirt error under /api/ is JSON with status 400, and a lock
timeout 409, instead of the HTML error page. This lives in the
existing ExceptionMiddleware, so existing settings need no change.
- Volume create/delete on an inactive pool answer 409, and invalid
volume data 400 with the serializer errors, instead of 200.
The new tests cover every view that returns with _back() without a
Referer and with a foreign one, the migrate failures on web and API,
the owner ids, the API error format and the volume statuses; nine of
the ten fail on the previous code.