Share Migration fails with empty files

[Rodrigo Barbieri]

If performing fallback migration, it fails if share has empty files. See trace below:

2016-08-16 07:01:24.632 ERROR manila.data.manager [req-5aeaaa9b-b5aa-4cbd-9602-db60c8ad777c 40f75400e1cb42e38ed9c2457946ac89 aa2c5f95139e4db89982b510053e18f0] Failed to copy contents from instance cd8a0847-5272-4c52-840b-b93676694055 to instance 9e720da1-15c1-4946-8bd7-0148bb15e096.
2016-08-16 07:01:24.632 TRACE manila.data.manager Traceback (most recent call last):
2016-08-16 07:01:24.632 TRACE manila.data.manager File "/opt/stack/manila/manila/data/manager.py", line 90, in migration_start
2016-08-16 07:01:24.632 TRACE manila.data.manager migration_info_dest)
2016-08-16 07:01:24.632 TRACE manila.data.manager File "/opt/stack/manila/manila/data/manager.py", line 282, in _copy_share_data
2016-08-16 07:01:24.632 TRACE manila.data.manager raise exception.ShareDataCopyFailed(reason=msg)
2016-08-16 07:01:24.632 TRACE manila.data.manager ShareDataCopyFailed: Share Data copy failed: Copying data from share instance cd8a0847-5272-4c52-840b-b93676694055 to 9e720da1-15c1-4946-8bd7-0148bb15e096 did not succeed.
2016-08-16 07:01:24.632 TRACE manila.data.manager
2016-08-16 07:01:24.636 WARNING manila.db.sqlalchemy.models [req-5aeaaa9b-b5aa-4cbd-9602-db60c8ad777c 40f75400e1cb42e38ed9c2457946ac89 aa2c5f95139e4db89982b510053e18f0] Property 'host' is deprecated. Please use appropriate property from share instance.
2016-08-16 07:01:24.637 DEBUG oslo_messaging._drivers.amqpdriver [req-5aeaaa9b-b5aa-4cbd-9602-db60c8ad777c 40f75400e1cb42e38ed9c2457946ac89 aa2c5f95139e4db89982b510053e18f0] CAST unique_id: d6436953ff834d9fa5375c3b2b648526 exchange 'openstack' topic 'manila-share' from (pid=5640) _send /usr/local/lib/python2.7/dist-packages/oslo_messaging/_drivers/amqpdriver.py:448
2016-08-16 07:01:24.640 ERROR oslo_messaging.rpc.server [req-5aeaaa9b-b5aa-4cbd-9602-db60c8ad777c 40f75400e1cb42e38ed9c2457946ac89 aa2c5f95139e4db89982b510053e18f0] Exception during message handling
2016-08-16 07:01:24.640 TRACE oslo_messaging.rpc.server Traceback (most recent call last):
2016-08-16 07:01:24.640 TRACE oslo_messaging.rpc.server File "/usr/local/lib/python2.7/dist-packages/oslo_messaging/rpc/server.py", line 133, in _process_incoming
2016-08-16 07:01:24.640 TRACE oslo_messaging.rpc.server res = self.dispatcher.dispatch(message)
2016-08-16 07:01:24.640 TRACE oslo_messaging.rpc.server File "/usr/local/lib/python2.7/dist-packages/oslo_messaging/rpc/dispatcher.py", line 150, in dispatch
2016-08-16 07:01:24.640 TRACE oslo_messaging.rpc.server return self._do_dispatch(endpoint, method, ctxt, args)
2016-08-16 07:01:24.640 TRACE oslo_messaging.rpc.server File "/usr/local/lib/python2.7/dist-packages/oslo_messaging/rpc/dispatcher.py", line 121, in _do_dispatch
2016-08-16 07:01:24.640 TRACE oslo_messaging.rpc.server result = func(ctxt, **new_args)
2016-08-16 07:01:24.640 TRACE oslo_messaging.rpc.server File "/opt/stack/manila/manila/data/manager.py", line 105, in migration_start
2016-08-16 07:01:24.640 TRACE oslo_messaging.rpc.server raise exception.ShareDataCopyFailed(reason=msg)
2016-08-16 07:01:24.640 TRACE oslo_messaging.rpc.server ShareDataCopyFailed: Share Data copy failed: Failed to copy contents from instance cd8a0847-5272-4c52-840b-b93676694055 to instance 9e720da1-15c1-4946-8bd7-0148bb15e096.
2016-08-16 07:01:24.640 TRACE oslo_messaging.rpc.server

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/355946

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/355946
Committed: https://git.openstack.org/cgit/openstack/manila/commit/?id=e4ddb090aede72b5a40cfaaa15bb2ff72d2a1e89
Submitter: Jenkins
Branch: master

commit e4ddb090aede72b5a40cfaaa15bb2ff72d2a1e89
Author: Rodrigo Barbieri <email address hidden>
Date: Tue Aug 16 10:49:35 2016 -0300

    Fix fallback share migration with empty files

    Fallback share migration fails with empty files. This patch fixes it
    by performing additional checks to address this specific scenario.

    Change-Id: I36d59740b4e52005e6025e5df5989bf55d6bade4
    Closes-bug: #1613713

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/manila 3.0.0.0b3 development milestone.