---
features:
  - |
    Inclusion of a project_id in API URLs is now optional. The `Block Storage
    API V3 <https://docs.openstack.org/api-ref/block-storage/v3>`_ reference
    guide continues to show URLs with a project_id because the legacy behavior
    continues to be supported.

    A new API microversion V3.67 is introduced to inform clients when
    inclusion of a project_id in API URLs is optional. The V3.67 microversion
    is only used as an indicator that the API accepts a URL without a
    project_id, and this applies to all requests regardless of the
    microversion in the request. For example, an API node serving V3.67 or
    greater will accept a URL without a project_id even if the request asks
    for V3.0. Likewise, it will accept a URL containing a project_id even if
    the request asks for V3.67.
upgrade:
  - |
    Upgrades are not affected by the new functionality whereby a project_id
    is no longer required in API URLs. The legacy behavior in which a
    project_id is included in the URL continues to be supported.

    Detection of whether a URL includes a project_id is based on the value of
    a new ``project_id_regex`` option.  The default value matches UUIDs
    created by keystone.