'Return an index listing of images available to the request.
:param req: `wsgi.Request` object'

@wsgi.Controller.api_version('2.1', MAX_PROXY_API_SUPPORT_VERSION)
@extensions.expected_errors(400)
def index(self, req):

    context = req.environ['nova.context']
    filters = self._get_filters(req)
    page_params = common.get_pagination_params(req)
    try:
        images = self._image_api.get_all(context, filters=filters, **page_params)
    except exception.Invalid as e:
        raise webob.exc.HTTPBadRequest(explanation=e.format_message())
    return self._view_builder.index(req, images)
