save_and_reraise_exception: sometimes logging original exception is undesired

[Oleg Bondarev]

In some cases the whole purpose of exception handler is to reraise proper type of exception - for such cases there is often no need to log original exception being dropped as described here: https://bugs.launchpad.net/neutron/+bug/1288188

The proposal would be to add 'log_orig_exception' flag simular to 'reraise' to let user omit logging original exception. Example of usage:

        try:
            res = self._get_by_id(context, model, id)
        except exc.NoResultFound:
            with excutils.save_and_reraise_exception() as ctx:
                ctx.log_orig_exception = False
                if issubclass(model, Vip):
                    raise loadbalancer.VipNotFound(vip_id=id)
                elif issubclass(model, Pool):
                    raise loadbalancer.PoolNotFound(pool_id=id)
                elif issubclass(model, Member):
                    raise loadbalancer.MemberNotFound(member_id=id)
                elif issubclass(model, HealthMonitor):
                    raise loadbalancer.HealthMonitorNotFound(monitor_id=id)
                # if no match - log original exception
                ctx.log_orig_exception = True
        return res

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/80222

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/80222
Committed: https://git.openstack.org/cgit/openstack/oslo-incubator/commit/?id=33a2cee6a690ecfdb2cecfe8f01b0b1dacb5bd17
Submitter: Jenkins
Branch: master

commit 33a2cee6a690ecfdb2cecfe8f01b0b1dacb5bd17
Author: Oleg Bondarev <email address hidden>
Date: Thu Mar 13 13:32:09 2014 +0400

    save_and_reraise_exception: make logging respect the reraise parameter

    Do not log original exception if reraise is set to False

    Closes-Bug: #1291850
    Related-Bug: #1288188

    Change-Id: Icd5fcba25c2cd549cee70353a7a62d83bfe1255b