ISCSIDriver has no 'target_helper' member

[Eric Harney]

$ pylint -E cinder/volume/driver.py
************* Module cinder.volume.driver
E:1046,12: Instance of 'ISCSIDriver' has no 'target_helper' member (no-member)
E:1064,12: Instance of 'ISCSIDriver' has no 'target_helper' member (no-member)

1045 if CONF.iscsi_helper == 'lioadm':
1046 self.target_helper.initialize_connection(volume, connector)

https://review.openstack.org/#/c/130399/ put code into driver.py that is specific to the LVM driver.

[John Griffith (john-griffith)]

Additional info: if you set the iscsi_helper to lioadm in this case, any driver that used to inherit from the base iSCSIDriver class for initialize_connection will fail and stack trace.

The reason is that the iscsi_helper is set in global CONF so if set to lioadm (even if not used) will always eval to true in that method and attempt the target_helper.initialize_connection call; but most drivers don't need this and won't have it so we'll fail for the error described in the pylint output above.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/141660

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/141660
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=7095e1c5a7477ca77c8698d96a969a7d78090a18
Submitter: Jenkins
Branch: master

commit 7095e1c5a7477ca77c8698d96a969a7d78090a18
Author: John Griffith <email address hidden>
Date: Sun Dec 14 12:02:30 2014 -0700

    Remove iscsi_helper calls from base iscsi driver

    There are a number of drivers that inherit from the base
    iscsi driver, using the base implementation of initialize_connection
    and terminate_connection. These drivers also don't have iscsi_helper
    defined.

    We've kept all iscsi_helper specific code in the tgt helpers
    themselves, or in the various versions of the LVM driver
    which is where they belong.

    Over time however there have been some iscsi_helper specific
    calls that have crept in to the base volume.driver:ISCSIDriver
    class. These were LIO specific calls and as a result when a
    configuration is set with multi-backend to use lioadm as the
    target helper, or even if it's not used but the default iscsi_helper
    is set to lioadm the initialize_connection and terminate_connection
    calls will try and access the LIO specific calls and raise because
    the drivers inheriting from this class don't have target_helper
    members.

    This went unnoticed mostly because there's no significant LIO testing
    in place and there were no distros setting LIO as the default iscsi_helper,
    it appears that this has changed however.

    This patch moves the LIO specific calls back where they belong
    and keeps the base ISCSIDriver generic. I've also added a test
    case for this in the SolidFire driver because it's impacted by
    this.

    Change-Id: Ibe010b62bb2518685753dd515326e56ffcc99cea
    Closes-Bug: #1400804

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/icehouse
Review: https://review.openstack.org/183464

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/juno
Review: https://review.openstack.org/183465

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/183465
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=9c0a64f3d7153bc262ce4fa0280a895992a9994f
Submitter: Jenkins
Branch: stable/juno

commit 9c0a64f3d7153bc262ce4fa0280a895992a9994f
Author: John Griffith <email address hidden>
Date: Sun Dec 14 12:02:30 2014 -0700

    Remove iscsi_helper calls from base iscsi driver

    There are a number of drivers that inherit from the base
    iscsi driver, using the base implementation of initialize_connection
    and terminate_connection. These drivers also don't have iscsi_helper
    defined.

    We've kept all iscsi_helper specific code in the tgt helpers
    themselves, or in the various versions of the LVM driver
    which is where they belong.

    Over time however there have been some iscsi_helper specific
    calls that have crept in to the base volume.driver:ISCSIDriver
    class. These were LIO specific calls and as a result when a
    configuration is set with multi-backend to use lioadm as the
    target helper, or even if it's not used but the default iscsi_helper
    is set to lioadm the initialize_connection and terminate_connection
    calls will try and access the LIO specific calls and raise because
    the drivers inheriting from this class don't have target_helper
    members.

    This went unnoticed mostly because there's no significant LIO testing
    in place and there were no distros setting LIO as the default iscsi_helper,
    it appears that this has changed however.

    This patch moves the LIO specific calls back where they belong
    and keeps the base ISCSIDriver generic. I've also added a test
    case for this in the SolidFire driver because it's impacted by
    this.

    Change-Id: Ibe010b62bb2518685753dd515326e56ffcc99cea
    Closes-Bug: #1400804
    (cherry picked from commit 7095e1c5a7477ca77c8698d96a969a7d78090a18)

[OpenStack Infra (hudson-openstack)]

Change abandoned by Gorka Eguileor (<email address hidden>) on branch: stable/icehouse
Review: https://review.openstack.org/183464
Reason: Icehouse is on Security Patches only.