---
features:
  - |
    Glance is now packaged with a WSGI script entrypoint, enabling it to be
    run as a WSGI application hosted by a performant web server.  See `Running
    Glance in HTTPD
    <https://docs.openstack.org/glance/latest/admin/apache-httpd.html>`_
    in the Glance documentation for details.

    There are some limitations with this method of deploying Glance and we
    do not recommend its use in production environments at this time.  See
    the `Known Issues`_ section of this document for more information.

issues:
  - |
    Although support has been added for Glance to be run as a WSGI application
    hosted by a web server, the atypical nature of the Images APIs provided by
    Glance, which enable transfer of copious amounts of image data, makes it
    difficult for this approach to work without careful configuration.  Glance
    relies on the use of chunked transfer encoding for image uploads, and
    the support of chunked transfer encoding is not required by the
    `WSGI specification`_.

    The Glance documentation section `Running Glance in HTTPD`_ outlines some
    approaches to use (and not to use) Glance with the Apache httpd server. This
    is the way Glance is configured as a WSGI application in devstack, so it's
    the method with which we've had the most experience.  If you try deploying
    Glance using a different web server, please consider contributing your
    findings to the Glance documentation.

    Currently, we are experiencing some problems in the gate when Glance is
    configured to run in devstack following the guidelines recommended in the
    documentation.  You can follow `Bug 1703856`_ to learn more.

    As far as the Glance team can determine, the difficulties running Glance
    as a WSGI application are caused by issues external to Glance.  Thus
    the Glance team recommends that Glance be run in its normal standalone
    configuration, particularly in production environments.  If you choose
    to run Glance as a WSGI application in a web server, be sure to test
    your installation carefully with realistic usage scenarios.

    .. _`WSGI specification`: https://www.python.org/dev/peps/pep-0333/
    .. _`Running Glance in HTTPD`: https://docs.openstack.org/glance/latest/admin/apache-httpd.html
    .. _`Bug 1703856`: https://bugs.launchpad.net/glance/+bug/1703856