Log module: memory footprint size used in contextual information twice bigger than expected

[Bertrand Lallau]

The log ContextAdapter used to specify contextual informations in logging output produce a context twice bigger than expected ("extra" informations are duplicated).
Actually the following is generated:

kwargs={
    'extra': {
        'project_name': 'project_name',
        'extra': {
            'project_name': 'project_name',
            'timestamp': '2014-01-13T09: 10: 10.942287',
            'auth_token': '47b920091df0492ca16314e22c3f5ff9',
            'remote_address': '127.0.0.1',
            'quota_class': None,
            'is_admin': False,
            'user': '6d029d604ed54d8e93ccae62d665aa64',
            'service_catalog': [

            ],
            'tenant': '1b7a085905d84b3793d58f219774a86a',
            'user_id': '6d029d604ed54d8e93ccae62d665aa64',
            'roles': [
                'user'
            ],
            'project': 'nova.api.openstack.compute.servers',
            'instance': '',
            'version': 'unknown',
            'read_deleted': 'no',
            'request_id': 'req-128e3666-57a9-44e1-a60a-a16a099b0da9',
            'instance_lock_checked': False,
            'project_id': '1b7a085905d84b3793d58f219774a86a',
            'user_name': 'project_name'
        },
        'timestamp': '2014-01-13T09: 10: 10.942287',
        'auth_token': '47b920091df0492ca16314e22c3f5ff9',
        'remote_address': '127.0.0.1',
        'quota_class': None,
        'is_admin': False,
        'user': '6d029d604ed54d8e93ccae62d665aa64',
        'service_catalog': [

        ],
        'tenant': '1b7a085905d84b3793d58f219774a86a',
        'user_id': '6d029d604ed54d8e93ccae62d665aa64',
        'roles': [
            'user'
        ],
        'project': 'nova.api.openstack.compute.servers',
        'instance': '',
        'version': 'unknown',
        'read_deleted': 'no',
        'request_id': 'req-128e3666-57a9-44e1-a60a-a16a099b0da9',
        'instance_lock_checked': False,
        'project_id': '1b7a085905d84b3793d58f219774a86a',
        'user_name': 'project_name'
    }
}

It should be:

kwargs={
    'extra': {
        'project_name': 'project_name',
        'timestamp': '2014-01-13T09: 10: 10.942287',
        'auth_token': '47b920091df0492ca16314e22c3f5ff9',
        'remote_address': '127.0.0.1',
        'quota_class': None,
        'is_admin': False,
        'user': '6d029d604ed54d8e93ccae62d665aa64',
        'service_catalog': [

        ],
        'tenant': '1b7a085905d84b3793d58f219774a86a',
        'user_id': '6d029d604ed54d8e93ccae62d665aa64',
        'roles': [
            'user'
        ],
        'project': 'nova.api.openstack.compute.servers',
        'instance': '',
        'version': 'unknown',
        'read_deleted': 'no',
        'request_id': 'req-128e3666-57a9-44e1-a60a-a16a099b0da9',
        'instance_lock_checked': False,
        'project_id': '1b7a085905d84b3793d58f219774a86a',
        'user_name': 'project_name'
    }
}

ContextAdapter is called each time an Openstack service produced a log,
hence memory impacted is really not insignificant.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/66458

[Balazs Gibizer (balazs-gibizer)]

It seems the original problem does not exists in the current oslo.log lib, see https://github.com/openstack/oslo.log/blob/master/oslo_log/log.py#L165