doc: Add configuration reference

Previously most (not all) openstack_auth configuration options
are documented in the horizon documentation.
It would be nice if we have the config reference in the same repo
so that we can easily manage the contents.

Horizon document will be updated to refer to this.

Change-Id: Ie1986a77bc5d69e27ae52f3b59377a41c3462e2b

2 files changed, 377 insertions, 0 deletions

diff --git a/doc/source/configuration/index.rst b/doc/source/configuration/index.rst
new file mode 100644
index 0000000..b442a3f
--- /dev/null
+++ b/doc/source/configuration/index.rst
@@ -0,0 +1,376 @@
+=============
+Configuration
+=============
+
+Django OpenStack Auth is configured through Django ``settings.py`` file.
+In most cases it is used combined with the OpenStack Dashboard,
+so the settings file will be ``local/local_settings.py`` file
+in your OpenStack Dashboard deployment.
+
+This page covers the configuration options referred by Django OpenStack Auth.
+
+:ref:`Some settings <settings-shared-with-horizon>` are also referred to
+by Horizon. Configure them carefully.
+
+General settings
+================
+
+``AUTHENTICATION_PLUGINS``
+--------------------------
+
+Default: ``['openstack_auth.plugin.password.PasswordPlugin', 'openstack_auth.plugin.token.TokenPlugin']``
+
+A list of authentication plugins to be used.
+In most cases, there is no need to configure this.
+
+``AVAILABLE_REGIONS``
+---------------------
+
+Default: ``None``
+
+A list of tuples which define multiple regions. The tuple format is
+``('http://{{ keystone_host }}:5000/v2.0', '{{ region_name }}')``. If any regions
+are specified the login form will have a dropdown selector for authenticating
+to the appropriate region, and there will be a region switcher dropdown in
+the site header when logged in.
+
+You should also define ``OPENSTACK_KEYSTONE_URL`` to indicate which of
+the regions is the default one.
+
+``OPENSTACK_API_VERSIONS``
+--------------------------
+
+Default::
+
+    {
+        "identity": 2.0,
+        ...,
+    }
+
+Overrides for OpenStack API versions. Use this setting to force the
+OpenStack dashboard to use a specific API version for a given service API.
+Django OpenStack Auth refers to only the ``"identity"`` entry.
+The current valid values are "2.0" or "3".
+
+.. note::
+
+   See `Horizon settings
+   <https://docs.openstack.org/developer/horizon/install/settings.html#openstack-api-versions>`__
+   for the full description of this setting.
+
+``OPENSTACK_ENDPOINT_TYPE``
+---------------------------
+
+Default: ``"publicURL"``
+
+A string which specifies the endpoint type to use for the endpoints in the
+Keystone service catalog. The default value for all services except for
+identity is ``"publicURL"``. The default value for the identity service is
+``"internalURL"``.
+
+``OPENSTACK_KEYSTONE_ADMIN_ROLES``
+----------------------------------
+
+Default: ``["admin"]``
+
+The list of roles that have administrator privileges in this OpenStack
+installation. This check is very basic and essentially only works with
+keystone v2.0 and v3 with the default policy file. The setting assumes there
+is a common ``admin`` like role(s) across services. Example uses of this
+setting are:
+
+* to rename the ``admin`` role to ``cloud-admin``
+* allowing multiple roles to have administrative privileges, like
+  ``["admin", "cloud-admin", "net-op"]``
+
+``OPENSTACK_KEYSTONE_DEFAULT_DOMAIN``
+-------------------------------------
+
+Default: ``"Default"``
+
+Overrides the default domain used when running on single-domain model
+with Keystone V3. All entities will be created in the default domain.
+
+.. note::
+
+   This value must be the name of the default domain, NOT the ID.
+   Also, you will most likely have a value in the keystone policy file like
+   ``"cloud_admin": "rule:admin_required and domain_id:<your domain id>"``.
+   This value must be the name of the domain whose ID is specified there.
+
+``OPENSTACK_KEYSTONE_MULTIDOMAIN_SUPPORT``
+------------------------------------------
+
+Default: ``False``
+
+Set this to True if running on multi-domain model. When this is enabled, it
+will require user to enter the Domain name in addition to username for login.
+
+``OPENSTACK_KEYSTONE_URL``
+--------------------------
+
+Default: ``"http://%s:5000/v2.0" % OPENSTACK_HOST``
+
+The full URL for the Keystone endpoint used for authentication. Unless you
+are using HTTPS, running your Keystone server on a nonstandard port, or using
+a nonstandard URL scheme you shouldn't need to touch this setting.
+
+``OPENSTACK_SSL_CACERT``
+------------------------
+
+Default: ``None``
+
+When unset or set to ``None`` the default CA certificate on the system is used
+for SSL verification.
+
+When set with the path to a custom CA certificate file, this overrides use of
+the default system CA certificate. This custom certificate is used to verify all
+connections to openstack services when making API calls.
+
+``OPENSTACK_SSL_NO_VERIFY``
+---------------------------
+
+Default: ``False``
+
+Disable SSL certificate checks in the OpenStack clients (useful for self-signed
+certificates).
+
+``OPENSTACK_TOKEN_HASH_ALGORITHM``
+----------------------------------
+
+Default: ``"md5"``
+
+The hash algorithm to use for authentication tokens. This must match the hash
+algorithm that the identity (Keystone) server and the auth_token middleware
+are using. Allowed values are the algorithms supported by Python's hashlib
+library.
+
+``OPENSTACK_TOKEN_HASH_ENABLED``
+--------------------------------
+
+(Deprecated)
+
+Default: ``True``
+
+Hashing tokens from Keystone keeps the Horizon session data smaller, but it
+doesn't work in some cases when using PKI tokens.  Uncomment this value and
+set it to False if using PKI tokens and there are 401 errors due to token
+hashing.
+
+This option is now marked as "deprecated" and will be removed in Ocata or a
+later release. PKI tokens currently work with hashing, and Keystone will soon
+deprecate usage of PKI tokens.
+
+``PASSWORD_EXPIRES_WARNING_THRESHOLD_DAYS``
+-------------------------------------------
+
+Default: ``-1``
+
+Password will have an expiration date when using keystone v3 and enabling the
+feature. This setting allows you to set the number of days that the user will
+be alerted prior to the password expiration. Once the password expires keystone
+will deny the access and users must contact an admin to change their password.
+Setting this value to ``N`` days means the user will be alerted when the
+password expires in less than ``N+1`` days. ``-1`` disables the feature.
+
+``POLICY_FILES``
+----------------
+
+Default: ``{'identity': 'keystone_policy.json', 'compute': 'nova_policy.json'}``
+
+This should essentially be the mapping of the contents of ``POLICY_FILES_PATH``
+to service types.  When policy.json files are added to ``POLICY_FILES_PATH``,
+they should be included here too.
+
+``POLICY_FILES_PATH``
+---------------------
+
+Default:  ``os.path.join(ROOT_PATH, "conf")``
+
+Specifies where service based policy files are located. These are used to
+define the policy rules actions are verified against.
+
+``SECURE_PROXY_ADDR_HEADER``
+----------------------------
+
+Default: ``False``
+
+If horizon is behind a proxy server and the proxy is configured, the IP address
+from request is passed using header variables inside the request. The header
+name depends on a proxy or a load-balancer. This setting specifies the name of
+the header with remote IP address. The main use is for authentication log
+(success or fail) displaing the IP address of the user.
+The commom value for this setting is ``HTTP_X_REAL_IP`` or
+``HTTP_X_FORWARDED_FOR``.
+If not present, then ``REMOTE_ADDR`` header is used. (``REMOTE_ADDR`` is the
+field of Django HttpRequest object which contains IP address of the client.)
+
+``SESSION_TIMEOUT``
+-------------------
+
+Default: ``"3600"``
+
+This ``SESSION_TIMEOUT`` is a method to supercede the token timeout with a
+shorter horizon session timeout (in seconds).  So if your token expires in
+60 minutes, a value of 1800 will log users out after 30 minutes.
+
+``TOKEN_DELETION_DISABLED``
+---------------------------
+
+Default: ``False``
+
+This setting allows deployers to control whether a token is deleted on log out.
+This can be helpful when there are often long running processes being run
+in the Horizon environment.
+
+``TOKEN_TIMEOUT_MARGIN``
+------------------------
+
+Default: ``0``
+
+A time margin in seconds to subtract from the real token's validity.
+An example usage is that the token can be valid once the middleware
+passed, and invalid (timed-out) during a view rendering and this
+generates authorization errors during the view rendering.
+By setting this value to some smaller seconds, you can avoid token
+expiration during a view rendering.
+
+``WEBROOT``
+-----------
+
+Default: ``"/"``
+
+Specifies the location where the access to the dashboard is configured in
+the web server.
+
+For example, if you're accessing the Dashboard via
+https://<your server>/dashboard, you would set this to ``"/dashboard/"``.
+
+.. note::
+
+    Additional settings may be required in the config files of your webserver
+    of choice. For example to make ``"/dashboard/"`` the web root in Apache,
+    the ``"sites-available/horizon.conf"`` requires a couple of additional
+    aliases set::
+
+        Alias /dashboard/static %HORIZON_DIR%/static
+
+        Alias /dashboard/media %HORIZON_DIR%/openstack_dashboard/static
+
+    Apache also requires changing your WSGIScriptAlias to reflect the desired
+    path.  For example, you'd replace ``/`` with ``/dashboard`` for the
+    alias.
+
+Web SSO (Single Sign On) settings
+=================================
+
+``WEBSSO_ENABLED``
+------------------
+
+Default: ``False``
+
+Enables keystone web single-sign-on if set to True. For this feature to work,
+make sure that you are using Keystone V3 and Django OpenStack Auth V1.2.0 or
+later.
+
+``WEBSSO_INITIAL_CHOICE``
+-------------------------
+
+Default: ``"credentials"``
+
+Determines the default authentication mechanism. When user lands on the login
+page, this is the first choice they will see.
+
+``WEBSSO_CHOICES``
+------------------
+
+Default::
+
+        (
+          ("credentials", _("Keystone Credentials")),
+          ("oidc", _("OpenID Connect")),
+          ("saml2", _("Security Assertion Markup Language"))
+        )
+
+This is the list of authentication mechanisms available to the user. It
+includes Keystone federation protocols such as OpenID Connect and SAML, and
+also keys that map to specific identity provider and federation protocol
+combinations (as defined in ``WEBSSO_IDP_MAPPING``). The list of choices is
+completely configurable, so as long as the id remains intact. Do not remove
+the credentials mechanism unless you are sure. Once removed, even admins will
+have no way to log into the system via the dashboard.
+
+``WEBSSO_IDP_MAPPING``
+----------------------
+
+Default: ``{}``
+
+A dictionary of specific identity provider and federation protocol combinations.
+From the selected authentication mechanism, the value will be looked up as keys
+in the dictionary. If a match is found, it will redirect the user to a identity
+provider and federation protocol specific WebSSO endpoint in keystone, otherwise
+it will use the value as the protocol_id when redirecting to the WebSSO by
+protocol endpoint.
+
+Example::
+
+        WEBSSO_CHOICES =  (
+            ("credentials", _("Keystone Credentials")),
+            ("oidc", _("OpenID Connect")),
+            ("saml2", _("Security Assertion Markup Language")),
+            ("acme_oidc", "ACME - OpenID Connect"),
+            ("acme_saml2", "ACME - SAML2")
+        )
+
+        WEBSSO_IDP_MAPPING = {
+            "acme_oidc": ("acme", "oidc"),
+            "acme_saml2": ("acme", "saml2")
+        }
+
+.. note::
+  The value is expected to be a tuple formatted as: (<idp_id>, <protocol_id>).
+
+K2K (Keystone to Keystone) Federation settings
+==============================================
+
+``KEYSTONE_PROVIDER_IDP_NAME``
+------------------------------
+
+Default: ``Local Keystone``
+
+The Keystone Provider drop down uses Keystone to Keystone federation
+to switch between Keystone service providers.
+This sets display name for Identity Provider (dropdown display name).
+
+``KEYSTONE_PROVIDER_IDP_ID``
+----------------------------
+
+Default:: ``localkeystone``
+
+This ID is used for only for comparison with the service provider IDs.
+This ID should not match any service provider IDs.
+
+.. _settings-shared-with-horizon:
+
+Settings shared with Horizon
+============================
+
+The following settings in Django OpenStack Auth are also used by Horizon.
+
+* ``AVAILABLE_REGIONS``
+* ``OPENSTACK_API_VERSIONS``
+* ``OPENSTACK_KEYSTONE_URL``
+* ``OPENSTACK_ENDPOINT_TYPE``
+* ``OPENSTACK_SSL_CACERT``
+* ``OPENSTACK_SSL_NO_VERIFY``
+* ``WEBROOT``
+
+Django OpenStack Auth also refers to the following Django settings.
+For more detail, see `Django settings documentation
+<https://docs.djangoproject.com/en/1.11/ref/settings/#auth>`__.
+They are usually configured as part of Horizon settings.
+
+* ``LOGIN_REDIRECT_URL``
+* ``LOGIN_URL``
+* ``SESSION_ENGINE``
+* ``USE_TZ``
diff --git a/doc/source/index.rst b/doc/source/index.rst
index 9f93215..d9ba571 100644
--- a/doc/source/index.rst
+++ b/doc/source/index.rst
@@ -12,6 +12,7 @@ The current version is designed to work with the Keystone V2 or V3 API.
    :maxdepth: 2
 
    install/index
+   configuration/index
    reference/index
 
 * :ref:`genindex`