Move auth token opts calculation into auth_token

The list of all auth token opts is currently calculated in opts.py.
That module is included in auth_token/__init__.py, which in turn owns
some opts that are needed by the former.

This creates a circular import dependency.

In order to fix such situation, this patch proposes to move the auth
token opts calculation into auth_token/__init__.py, so that it will
no longer need opts.py.

Co-Authored-By: Alfredo Moralejo <amoralej@redhat.com>

Closes-Bug: #1591913
Change-Id: If67d8bdb68a5ab9c07b960ad0111e2310ad82c83

keystonemiddleware/auth_token/__init__.py

@@ -207,6 +207,7 @@ object is stored.
 """
 
 import binascii
+import copy
 import datetime
 import logging
 
@@ -228,11 +229,11 @@ from keystonemiddleware.auth_token import _base
 from keystonemiddleware.auth_token import _cache
 from keystonemiddleware.auth_token import _exceptions as ksm_exceptions
 from keystonemiddleware.auth_token import _identity
+from keystonemiddleware.auth_token import _opts
 from keystonemiddleware.auth_token import _request
 from keystonemiddleware.auth_token import _revocations
 from keystonemiddleware.auth_token import _signing_dir
 from keystonemiddleware.auth_token import _user_plugin
-from keystonemiddleware import opts
 from keystonemiddleware.i18n import _, _LC, _LE, _LI, _LW
 
 
@@ -240,6 +241,36 @@ _LOG = logging.getLogger(__name__)
 _CACHE_INVALID_INDICATOR = 'invalid'
 
 
+AUTH_TOKEN_OPTS = [
+    (_base.AUTHTOKEN_GROUP,
+     _opts._OPTS + _auth.OPTS + loading.get_auth_common_conf_options())
+]
+
+
+def list_opts():
+    """Return a list of oslo_config options available in auth_token middleware.
+
+    The returned list includes all oslo_config options which may be registered
+    at runtime by the project.
+
+    Each element of the list is a tuple. The first element is the name of the
+    group under which the list of elements in the second element will be
+    registered. A group name of None corresponds to the [DEFAULT] group in
+    config files.
+
+    NOTE: This function is no longer used for oslo_config sample generation.
+    Some services rely on this function for listing ALL (including deprecated)
+    options and registering them into their own config objects which we do not
+    want for sample config files.
+
+    See: :py:func:`keystonemiddleware.auth_token._opts.list_opts` for sample
+    config files.
+
+    :returns: a list of (group_name, opts) tuples
+    """
+    return [(g, copy.deepcopy(o)) for g, o in AUTH_TOKEN_OPTS]
+
+
 class _BIND_MODE(object):
     DISABLED = 'disabled'
     PERMISSIVE = 'permissive'
@@ -464,7 +495,7 @@ class AuthProtocol(BaseAuthProtocol):
 
         self._conf = config.Config('auth_token',
                                    _base.AUTHTOKEN_GROUP,
-                                   opts.list_auth_token_opts(),
+                                   list_opts(),
                                    conf)
 
         super(AuthProtocol, self).__init__(

keystonemiddleware/opts.py

@@ -16,39 +16,8 @@ __all__ = (
     'list_auth_token_opts',
 )
 
-import copy
+from keystonemiddleware import auth_token
-
-from keystoneauth1 import loading
-
-from keystonemiddleware.auth_token import _auth
-from keystonemiddleware.auth_token import _base
-from keystonemiddleware.auth_token import _opts
-
-auth_token_opts = [
-    (_base.AUTHTOKEN_GROUP,
-     _opts._OPTS + _auth.OPTS + loading.get_auth_common_conf_options())
-]
 
 
 def list_auth_token_opts():
-    """Return a list of oslo_config options available in auth_token middleware.
+    return auth_token.list_opts()
-
-    The returned list includes all oslo_config options which may be registered
-    at runtime by the project.
-
-    Each element of the list is a tuple. The first element is the name of the
-    group under which the list of elements in the second element will be
-    registered. A group name of None corresponds to the [DEFAULT] group in
-    config files.
-
-    NOTE: This function is no longer used for oslo_config sample generation.
-    Some services rely on this function for listing ALL (including deprecated)
-    options and registering them into their own config objects which we do not
-    want for sample config files.
-
-    See: :py:func:`keystonemiddleware.auth_token._opts.list_opts` for sample
-    config files.
-
-    :returns: a list of (group_name, opts) tuples
-    """
-    return [(g, copy.deepcopy(o)) for g, o in auth_token_opts]