Adds support for RequestedAuthnContext SSO kwarg

Author: pandafy

djangosaml2/views.py

@@ -249,13 +249,21 @@ def get(self, request, *args, **kwargs):
 
         # SSO options
         sign_requests = getattr(conf, '_sp_authn_requests_signed', False)
-
-        if sign_requests:
-            csc = settings.SAML_CONFIG['service']['sp']
-            sso_kwargs["sigalg"] = csc.get('signing_algorithm',
-                                           saml2.xmldsig.SIG_RSA_SHA256)
-            sso_kwargs["digest_alg"] = csc.get('digest_algorithm',
-                                               saml2.xmldsig.DIGEST_SHA256)
+        sso_kwargs['requested_authn_context'] = getattr(
+            conf,
+            '_sp_requested_authn_context',
+            None
+        )
+        csc = settings.SAML_CONFIG.get(
+            'service',
+            None
+        ).get('sp', None)
+        if csc:
+            if sign_requests and csc:
+                sso_kwargs["sigalg"] = csc.get('signing_algorithm',
+                                            saml2.xmldsig.SIG_RSA_SHA256)
+                sso_kwargs["digest_alg"] = csc.get('digest_algorithm',
+                                                saml2.xmldsig.DIGEST_SHA256)
 
         # pysaml needs a string otherwise: "cannot serialize True (type bool)"
         if getattr(conf, '_sp_force_authn', False):