Differentiate between metadata NameIDFormat and AuthnRequest NameIDPolicy Format

The `name_id_format` configuration option is used to define

1. the value of the `<NameIDFormat>` metadata element
2. and the value of the `<NameIDPolicy>` `Format` attribute in an `AuthnRequest`

The configuration option to set what the value of `<NameIDFormat>` element is in the
metadata should be different from the configuration option to specify what should be
requested in an `AuthnRequest` through the `<NameIDPolicy Format="...">` attribute.

Introduce a new option (`name_id_policy_format`), or use the same name but scoped in a
specific section for metadata and AuthnRequest.

On the side of this, pysaml2 defaults to _transient_ as the `<NameIDPolicy
Format="...">` attribute value. To omit requesting a value for the `<NameIDPolicy
Format="">` attribute the value `"None"` (a string) must be set in the configuration.
This is unintuitive. It is better to be explicit and set transient to request a
transient NameID, than not setting a value and requesting transient by default. If no
value is set, no specific `<NameIDPolicy Format="...">` should be requested.

- Refactor the name_id_format usage
- Add name_id_policy_format configuration option
- Remove the "None" convention value

Signed-off-by: Ivan Kanakarakis <ivan.kanak@gmail.com>

1 files changed, 9 insertions, 7 deletions

diff --git a/src/saml2/metadata.py b/src/saml2/metadata.py
index b2317131..d80b41ac 100644
--- a/src/saml2/metadata.py
+++ b/src/saml2/metadata.py
@@ -379,13 +379,15 @@ def do_extensions(mname, item):
 
 
 def _do_nameid_format(cls, conf, typ):
-    namef = conf.getattr("name_id_format", typ)
-    if namef:
-        if isinstance(namef, six.string_types):
-            ids = [md.NameIDFormat(namef)]
-        else:
-            ids = [md.NameIDFormat(text=form) for form in namef]
-        setattr(cls, "name_id_format", ids)
+    name_id_format = conf.getattr("name_id_format", typ)
+    if not name_id_format:
+        return
+
+    if isinstance(name_id_format, six.string_types):
+        name_id_format = [name_id_format]
+
+    formats = [md.NameIDFormat(text=format) for format in name_id_format]
+    setattr(cls, "name_id_format", formats)
 
 
 def do_endpoints(conf, endpoints):