The 'tripleoclient.export.export_stack' contains a race condition

[Jiri Podivin]

Description
===========

The 'export_stack' function contains a race condition.
With the correct operation of the function depending on particular order of the 'tripleoclient.constants.EXPORT_DATA' dictionary item and presence of the the required json files.

If the requested file isn't found, and the loop has underwent one successful iteration immediately prior, the 'export_data' variable will be filled with the values obtained at during the previous successful iteration.

If the requested file isn't successfully found and decoded, the error, or warning, is still logged, but the execution continues with the following statements. [0]

As the 'export_data' still contains value obtained in previous iteration, the condition[1] will be cleared and the 'param' key in the 'data' dictionary will be filled with the value contained within the 'export_data' variable.

Source
------
    for export_key, export_param in constants.EXPORT_DATA.items():
        param = export_param["parameter"]
        if "file" in export_param:
            # get file data
            file = os.path.join(config_download_dir,
                                stack,
                                export_param["file"])
            if not os.path.exists(file):
    [0]-------> LOG.warning('File %s was not found during export' %
                            file)
            with open(file, 'r') as ff:
                try:
                    export_data = json.load(ff)
                except (TypeError, json.JSONDecodeError) as e:
                    LOG.error(
                        _('Could not read file %s') % file)
                    LOG.error(e)

        else:
            # get stack data
            export_data = oooutils.get_stack_output_item(
                            heat_stack, export_key)

        if export_data: <---------------------------------------[1]
            # When we export information from a cell controller stack
            # we don't want to filter.
            if "filter" in export_param and should_filter:
                for filter_key in export_param["filter"]:
                    if filter_key in export_data:
                        element = {filter_key: export_data[filter_key]}
                        data.setdefault(param, {}).update(element)
            else:
                data[param] = export_data

        else:
            raise Exception(
                "No data returned to export %s from." % param)

https://opendev.org/openstack/python-tripleoclient/src/branch/master/tripleoclient/export.py#L78-L115

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/openstack/python-tripleoclient/+/805409

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/python-tripleoclient/+/805409
Committed: https://opendev.org/openstack/python-tripleoclient/commit/fdd988948879ec20ac3b4c06a3097e52d94b795b
Submitter: "Zuul (22348)"
Branch: master

commit fdd988948879ec20ac3b4c06a3097e52d94b795b
Author: Jiri Podivin <email address hidden>
Date: Fri Aug 20 16:55:48 2021 +0200

    Eliminating a race condition in the export_stack function

    The correct export of the stack parameters no longer depends
    on order of the tripleclient.constants.EXPORT_DATA,
    as the lack of expected json file with parameters to export
    raises exception, rather than filling the requested key with
    data obtained in the previous iteration.

    The I/O logic was moved to the tripleoclient.utils to keep
    things more consistent.

    No longer necessary json import was removed.

    Tests were adjusted to mock more selectively.

    Closes-Bug: #1940685

    Signed-off-by: Jiri Podivin <email address hidden>
    Change-Id: Ia7fb232261eb00c53d4e9bb352e572568704000f

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/wallaby
Review: https://review.opendev.org/c/openstack/python-tripleoclient/+/807845

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/python-tripleoclient/+/807845
Committed: https://opendev.org/openstack/python-tripleoclient/commit/ef151db52ec1d7957be7850bb1bb7634c45a1bb4
Submitter: "Zuul (22348)"
Branch: stable/wallaby

commit ef151db52ec1d7957be7850bb1bb7634c45a1bb4
Author: Jiri Podivin <email address hidden>
Date: Fri Aug 20 16:55:48 2021 +0200

    Eliminating a race condition in the export_stack function

    The correct export of the stack parameters no longer depends
    on order of the tripleclient.constants.EXPORT_DATA,
    as the lack of expected json file with parameters to export
    raises exception, rather than filling the requested key with
    data obtained in the previous iteration.

    The I/O logic was moved to the tripleoclient.utils to keep
    things more consistent.

    No longer necessary json import was removed.

    Tests were adjusted to mock more selectively.

    Closes-Bug: #1940685

    Signed-off-by: Jiri Podivin <email address hidden>
    Change-Id: Ia7fb232261eb00c53d4e9bb352e572568704000f
    (cherry picked from commit fdd988948879ec20ac3b4c06a3097e52d94b795b)

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/python-tripleoclient 17.1.0 release.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/python-tripleoclient 16.5.0 release.