Comment 4 for bug 890888

Reviewed: https://review.openstack.org/11126
Committed: http://github.com/openstack/swift/commit/edd38035be4f64d547938f44fb2d96a72eeb672a
Submitter: Jenkins
Branch: master

commit edd38035be4f64d547938f44fb2d96a72eeb672a
Author: MORITA Kazutaka <email address hidden>
Date: Fri Aug 10 14:00:09 2012 +0900

    handle exception correctly in _make_app_iter_reader

    _make_app_iter_reader uses a queue to pass read data to
    _make_app_iter, and uses an empty string as a terminator. The problem
    is that it pushes the same terminator even if it fails to reads the
    data. If an exception happens before pushing all data to the queue,
    _make_app_iter exits without yielding all data. In that case,
    proxy-server stops in the middle of sending data, and a client waits
    for all data to come infinitely.

    This patch uses a boolean value for the terminator instead of an empty
    string to distinguish the results, and raises an exception in the
    error cases. Fixes bug 890888.

    Change-Id: Ie4d48025843aa1bb600446da6f4fc49f82a440bf