Migration 015 should not use internal Glance classes

[Dan Prince]

I recently made some Glance backend storage changes and was a bit surprised I had to change glance/db/sqlalchemy/migrate_repo/versions/015_quote_swift_credentials.py (a database migration) in order for tests to pass.

It would be best if Glance migrations did not rely on internal Glance classes when performing data migrations. If we need access to a backend storage class we should implement an inline version in this migration.

[Mark Washenberger (markwash)]

This also affects 017_quote_encrypted_swift_credentials.py

This is a big deal because the StoreLocation code could easily change, and thus break the expectations being placed on it in migrations. We also don't want to have to prevent beneficial changes in StoreLocation just because they might break migrations.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/24552

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/24552
Committed: http://github.com/openstack/glance/commit/62068a3cf9d8803a22f80c0fad7044861d3e3399
Submitter: Jenkins
Branch: master

commit 62068a3cf9d8803a22f80c0fad7044861d3e3399
Author: John Bresnahan <email address hidden>
Date: Fri Mar 15 09:41:26 2013 -1000

    Remove internal store references from migration 015

    Migration 015 was accessing a object internal to the swift store driver
    and changing its behavior in order to do the migration. This worked but
    it made the assumption that the driver logic would not change without
    also changing the migration code. These two should not be dependent
    upon each other. This patch removes all dependencies on swift from the
    migration code.

    Fixes bug: 1025746
    Change-Id: Ic9559ae809b8784d0992cb5275d3911a725110c8