Added test file for tests around authentication requests

Added a file for holding tests around authentication requests
and added a first test to test that the IdP code can pick the
correct location from SAML metadata using the
AssertionConsumerServiceIndex from an authentication request.

Author: skoranda

tests/test_71_authn_request.py

@@ -0,0 +1,37 @@
+from contextlib import closing
+from saml2.client import Saml2Client
+from saml2.server import Server
+
+
+def test_authn_request_with_acs_by_index():
+    # ACS index and location from SP metadata in servera.xml.
+    ACS_INDEX = '4'
+    ACS_LOCATION = 'http://lingon.catalogix.se:8087/another/path'
+
+    # Create SP using the configuration found in servera_conf.py.
+    sp = Saml2Client(config_file="servera_conf")
+
+    # Generate an authn request object that uses AssertionConsumerServiceIndex
+    # instead of AssertionConsumerServiceURL. The index with label ACS_INDEX
+    # exists in the SP metadata in servera.xml.
+    request_id, authn_request = sp.create_authn_request(
+                                sp.config.entityid,
+                                assertion_consumer_service_index=ACS_INDEX)
+
+    # Make sure the authn_request contains AssertionConsumerServiceIndex.
+    acs_index = getattr(authn_request,
+                        'assertion_consumer_service_index', None)
+
+    assert acs_index == ACS_INDEX
+
+    # Create IdP.
+    with closing(Server(config_file="idp_all_conf")) as idp:
+
+        # Ask the IdP to pick out the binding and destination from the
+        # authn_request.
+        binding, destination = idp.pick_binding("assertion_consumer_service",
+                                                request=authn_request)
+
+        # Make sure the IdP pick_binding method picks the correct location
+        # or destination based on the ACS index in the authn request.
+        assert destination == ACS_LOCATION