Hi Devs,
I want your opinion about bug: https://bugs.launchpad.net/nova/+bug/1680130
When user passes incorrect formatted UUID, volume UUID like:
11111111-2222-4444-5555--666666666666(please note double hyphen) for attaching
a volume to an instance using "volume-attach" API then it results into
DBDataError with following error message: "Data too long for column
'volume_id'". The reason is in database "block_device_mapping" table has
"volume_id" field of 36 characters only so while inserting data to the table
through 'BlockDeviceMapping' object it raises DBDaTaError.
In current code, volume_id is of 'UUID' format so it uses "is_uuid_like"[4]
method of oslo_utils and in this method, it removes all the hyphens and checks
32 length UUID and returns true or false. As
"11111111-2222-4444-5555--666666666666" this UUID treated as valid and further
it goes into database table for insertion, as its size is more than 36
characters it gives DBDataError.
There are various solutions we can apply to validate volume UUID in this case:
Solution 1:
We can restrict the length of volume UUID using maxlength property in schema
validation.
Advantage:
This solution is better than solution 2 and 3 as we can restrict the invalid
UUID at schema [1] level itself by adding 'maxLength'[2].
Solution 2:
Before creating a volume BDM object, we can check that the provided volume is
actually present or not.
Advantage:
Volume BDM creation can be avoided if the volume does not exists.
Disadvantage:
IMO this solution is not better because we need to change the current code.
Because in the current code after creating volume BDM it is checking volume is
exists or not.
We have to check volume existence before creating volume BDM object. For that
we need to modify the "_check_attach_and_reserve_volume" method [3]. But this
method get used at 3 places. According to it, we have to modify all the
occurrences as per behavior.
Solution 3:
We can check UUID in central place means in "is_uuid_like" method of oslo_utils
[4].
Advantage:
If we change the "is_uuid_like" method then same issue might be solved for the
rest of the APIs.
Disadvantage:
IMO this also not a better solution because if we change the "is_uuid_like"
method then it will affect on several different projects.
Please let me know your opinion for the same.
[1]
https://github.com/openstack/nova/blob/master/nova/api/openstack/compute/schemas/volumes.py#L65
[2]
https://github.com/openstack/nova/blob/master/nova/api/validation/parameter_types.py#L297
[3] https://github.com/openstack/nova/blob/master/nova/compute/api.py#L3721
[4]
https://github.com/openstack/oslo.utils/blob/master/oslo_utils/uuidutils.py#L45
______________________________________________________________________
Disclaimer: This email and any attachments are sent in strictest confidence
for the sole use of the addressee and may contain legally privileged,
confidential, and proprietary data. If you are not the intended recipient,
please advise the sender by replying promptly to this email and then delete
and destroy this email and any attachments without any further use, copying
or forwarding.
__________________________________________________________________________
OpenStack Development Mailing List (not for usage questions)
Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe
http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
