diff --git a/cas_server/auth.py b/cas_server/auth.py
index afcb722..d666ec5 100644
--- a/cas_server/auth.py
+++ b/cas_server/auth.py
@@ -171,7 +171,7 @@ class CASFederateAuth(AuthUser):
 
     def attributs(self):
         """return a dict of user attributes"""
-        if not self.user:
+        if not self.user:  # pragma: no cover (should not happen)
             return {}
         else:
             return self.user.attributs
diff --git a/cas_server/default_settings.py b/cas_server/default_settings.py
index 07b420e..be3f064 100644
--- a/cas_server/default_settings.py
+++ b/cas_server/default_settings.py
@@ -14,7 +14,6 @@ from django.conf import settings
 from django.contrib.staticfiles.templatetags.staticfiles import static
 
 import re
-import six
 
 
 def setting_default(name, default_value):
@@ -112,13 +111,10 @@ except AttributeError:
             key = settings.CAS_FEDERATE_PROVIDERS[key][2].lower()
         else:
             key = key.lower()
-        if isinstance(key, six.string_types) or isinstance(key, six.text_type):
-            return tuple(
-                int(num) if num else alpha
-                for num, alpha in __cas_federate_providers_list_sort.tokenize(key)
-            )
-        else:
-            return key
+        return tuple(
+            int(num) if num else alpha
+            for num, alpha in __cas_federate_providers_list_sort.tokenize(key)
+        )
     __cas_federate_providers_list_sort.tokenize = re.compile(r'(\d+)|(\D+)').findall
     __CAS_FEDERATE_PROVIDERS_LIST.sort(key=__cas_federate_providers_list_sort)
 
diff --git a/cas_server/federate.py b/cas_server/federate.py
index 453a778..2f6489a 100644
--- a/cas_server/federate.py
+++ b/cas_server/federate.py
@@ -15,6 +15,7 @@ from .cas import CASClient
 from .models import FederatedUser, FederateSLO, User
 
 from importlib import import_module
+from six.moves import urllib
 
 SessionStore = import_module(settings.SESSION_ENGINE).SessionStore
 
@@ -27,7 +28,7 @@ class CASFederateValidateUser(object):
     def __init__(self, provider, service_url):
         self.provider = provider
 
-        if provider in settings.CAS_FEDERATE_PROVIDERS:
+        if provider in settings.CAS_FEDERATE_PROVIDERS:  # pragma: no branch (should always be True)
             (server_url, version) = settings.CAS_FEDERATE_PROVIDERS[provider][:2]
             self.client = CASClient(
                 service_url=service_url,
@@ -44,9 +45,12 @@ class CASFederateValidateUser(object):
 
     def verify_ticket(self, ticket):
         """test `password` agains the user"""
-        if self.client is None:
+        if self.client is None:  # pragma: no cover (should not happen)
+            return False
+        try:
+            username, attributs = self.client.verify_ticket(ticket)[:2]
+        except urllib.error.URLError:
             return False
-        username, attributs = self.client.verify_ticket(ticket)[:2]
         if username is not None:
             if attributs is None:
                 attributs = {}
@@ -83,23 +87,20 @@ class CASFederateValidateUser(object):
 
     def clean_sessions(self, logout_request):
         try:
-            slos = self.client.get_saml_slos(logout_request)
-        except NameError:
+            slos = self.client.get_saml_slos(logout_request) or []
+        except NameError:  # pragma: no cover (should not happen)
             slos = []
         for slo in slos:
-            try:
-                for federate_slo in FederateSLO.objects.filter(ticket=slo.text):
-                    session = SessionStore(session_key=federate_slo.session_key)
-                    session.flush()
-                    try:
-                        user = User.objects.get(
-                            username=federate_slo.username,
-                            session_key=federate_slo.session_key
-                        )
-                        user.logout()
-                        user.delete()
-                    except User.DoesNotExist:
-                        pass
-                    federate_slo.delete()
-            except FederateSLO.DoesNotExist:
-                pass
+            for federate_slo in FederateSLO.objects.filter(ticket=slo.text):
+                session = SessionStore(session_key=federate_slo.session_key)
+                session.flush()
+                try:
+                    user = User.objects.get(
+                        username=federate_slo.username,
+                        session_key=federate_slo.session_key
+                    )
+                    user.logout()
+                    user.delete()
+                except User.DoesNotExist:  # pragma: no cover (should not happen)
+                    pass
+                federate_slo.delete()
diff --git a/cas_server/forms.py b/cas_server/forms.py
index b5cf4d0..dc0e866 100644
--- a/cas_server/forms.py
+++ b/cas_server/forms.py
@@ -31,6 +31,8 @@ class WarnForm(forms.Form):
 class FederateSelect(forms.Form):
     provider = forms.ChoiceField(
         label=_('Identity provider'),
+        # with use a lambda abstraction to delay the access to settings.CAS_FEDERATE_PROVIDERS
+        # this is usefull to use the override_settings decorator in tests
         choices=[
             (
                 p,
@@ -88,8 +90,12 @@ class FederateUserCredential(UserCredential):
             user = models.FederatedUser.objects.get(username=username, provider=provider)
             user.ticket = ""
             user.save()
-        except models.FederatedUser.DoesNotExist:
-            raise
+        # should not happed as is the FederatedUser do not exists, super should
+        # raise before a ValidationError("bad user")
+        except models.FederatedUser.DoesNotExist:  # pragma: no cover (should not happend)
+            raise forms.ValidationError(
+                _(u"User not found in the temporary database, please try to reconnect")
+            )
         return cleaned_data
 
 
diff --git a/cas_server/management/commands/cas_clean_federate.py b/cas_server/management/commands/cas_clean_federate.py
index 04e0608..8d91935 100644
--- a/cas_server/management/commands/cas_clean_federate.py
+++ b/cas_server/management/commands/cas_clean_federate.py
@@ -1,11 +1,7 @@
 from django.core.management.base import BaseCommand
 from django.utils.translation import ugettext_lazy as _
-from django.utils import timezone
-
-from datetime import timedelta
 
 from ... import models
-from ...default_settings import settings
 
 
 class Command(BaseCommand):
@@ -13,11 +9,5 @@ class Command(BaseCommand):
     help = _(u"Clean old federated users")
 
     def handle(self, *args, **options):
-        federated_users = models.FederatedUser.objects.filter(
-            last_update__lt=(timezone.now() - timedelta(seconds=settings.CAS_TICKET_TIMEOUT))
-        )
-        known_users = {user.username for user in models.User.objects.all()}
-        for user in federated_users:
-            if not ('%s@%s' % (user.username, user.provider)) in known_users:
-                user.delete()
+        models.FederatedUser.clean_old_entries()
         models.FederateSLO.clean_deleted_sessions()
diff --git a/cas_server/models.py b/cas_server/models.py
index aea270b..3d1f17f 100644
--- a/cas_server/models.py
+++ b/cas_server/models.py
@@ -46,6 +46,16 @@ class FederatedUser(models.Model):
     def __unicode__(self):
         return u"%s@%s" % (self.username, self.provider)
 
+    @classmethod
+    def clean_old_entries(cls):
+        federated_users = cls.objects.filter(
+            last_update__lt=(timezone.now() - timedelta(seconds=settings.CAS_TICKET_TIMEOUT))
+        )
+        known_users = {user.username for user in User.objects.all()}
+        for user in federated_users:
+            if not ('%s@%s' % (user.username, user.provider)) in known_users:
+                user.delete()
+
 
 class FederateSLO(models.Model):
     class Meta:
@@ -54,11 +64,6 @@ class FederateSLO(models.Model):
     session_key = models.CharField(max_length=40, blank=True, null=True)
     ticket = models.CharField(max_length=255)
 
-    @property
-    def provider(self):
-        component = self.username.split("@")
-        return component[-1]
-
     @classmethod
     def clean_deleted_sessions(cls):
         for federate_slo in cls.objects.all():
@@ -76,6 +81,14 @@ class User(models.Model):
     username = models.CharField(max_length=30)
     date = models.DateTimeField(auto_now=True)
 
+    def delete(self, *args, **kwargs):
+        if settings.CAS_FEDERATE:
+            FederateSLO.objects.filter(
+                username=self.username,
+                session_key=self.session_key
+            ).delete()
+        super(User, self).delete(*args, **kwargs)
+
     @classmethod
     def clean_old_entries(cls):
         """Remove users inactive since more that SESSION_COOKIE_AGE"""
diff --git a/cas_server/tests/mixin.py b/cas_server/tests/mixin.py
index ddbf2d2..4612fd2 100644
--- a/cas_server/tests/mixin.py
+++ b/cas_server/tests/mixin.py
@@ -191,3 +191,50 @@ class UserModels(object):
             username=settings.CAS_TEST_USER,
             session_key=client.session.session_key
         )
+
+
+class CanLogin(object):
+    """Assertion about login"""
+    def assert_logged(
+        self, client, response, warn=False,
+        code=200, username=settings.CAS_TEST_USER
+    ):
+        """Assertions testing that client is well authenticated"""
+        self.assertEqual(response.status_code, code)
+        # this message is displayed to the user upon successful authentication
+        self.assertIn(
+            (
+                b"You have successfully logged into "
+                b"the Central Authentication Service"
+            ),
+            response.content
+        )
+        # these session variables a set if usccessfully authenticated
+        self.assertEqual(client.session["username"], username)
+        self.assertIs(client.session["warn"], warn)
+        self.assertIs(client.session["authenticated"], True)
+
+        # on successfull authentication, a corresponding user object is created
+        self.assertTrue(
+            models.User.objects.get(
+                username=username,
+                session_key=client.session.session_key
+            )
+        )
+
+    def assert_login_failed(self, client, response, code=200):
+        """Assertions testing a failed login attempt"""
+        self.assertEqual(response.status_code, code)
+        # this message is displayed to the user upon successful authentication, so it should not
+        # appear
+        self.assertFalse(
+            (
+                b"You have successfully logged into "
+                b"the Central Authentication Service"
+            ) in response.content
+        )
+
+        # if authentication has failed, these session variables should not be set
+        self.assertTrue(client.session.get("username") is None)
+        self.assertTrue(client.session.get("warn") is None)
+        self.assertTrue(client.session.get("authenticated") is None)
diff --git a/cas_server/tests/test_federate.py b/cas_server/tests/test_federate.py
new file mode 100644
index 0000000..b4e76b2
--- /dev/null
+++ b/cas_server/tests/test_federate.py
@@ -0,0 +1,344 @@
+# -*- coding: utf-8 -*-
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+# FOR A PARTICULAR PURPOSE. See the GNU General Public License version 3 for
+# more details.
+#
+# You should have received a copy of the GNU General Public License version 3
+# along with this program; if not, write to the Free Software Foundation, Inc., 51
+# Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+#
+# (c) 2016 Valentin Samir
+"""tests for the CAS federate mode"""
+from cas_server import default_settings
+from cas_server.default_settings import settings
+
+import django
+from django.test import TestCase, Client
+from django.test.utils import override_settings
+
+from six.moves import reload_module
+
+from cas_server import utils, forms
+from cas_server.tests.mixin import BaseServicePattern, CanLogin
+from cas_server.tests import utils as tests_utils
+
+PROVIDERS = {
+    "example.com": ("http://127.0.0.1:8080", 1, "Example dot com"),
+    "example.org": ("http://127.0.0.1:8081", 2, "Example dot org"),
+    "example.net": ("http://127.0.0.1:8082", 3, "Example dot net"),
+    "example.test": ("http://127.0.0.1:8083", 'CAS_2_SAML_1_0'),
+}
+
+PROVIDERS_LIST = list(PROVIDERS.keys())
+PROVIDERS_LIST.sort()
+
+
+def getaddrinfo_mock(name, port, *args, **kwargs):
+    return [(2, 1, 6, '', ('127.0.0.1', 80))]
+
+
+@override_settings(
+    CAS_FEDERATE=True,
+    CAS_FEDERATE_PROVIDERS=PROVIDERS,
+    CAS_FEDERATE_PROVIDERS_LIST=PROVIDERS_LIST,
+    CAS_AUTH_CLASS="cas_server.auth.CASFederateAuth",
+    # test with a non ascii username
+    CAS_TEST_USER=u"dédé"
+)
+class FederateAuthLoginLogoutTestCase(TestCase, BaseServicePattern, CanLogin):
+    """tests for the views login logout and federate then the federated mode is enabled"""
+    def setUp(self):
+        """Prepare the test context"""
+        self.setup_service_patterns()
+        reload_module(forms)
+
+    def test_default_settings(self):
+        """default settings should populated some default variable then CAS_FEDERATE is True"""
+        provider_list = settings.CAS_FEDERATE_PROVIDERS_LIST
+        del settings.CAS_FEDERATE_PROVIDERS_LIST
+        del settings.CAS_AUTH_CLASS
+        reload_module(default_settings)
+        self.assertEqual(settings.CAS_FEDERATE_PROVIDERS_LIST, provider_list)
+        self.assertEqual(settings.CAS_AUTH_CLASS, "cas_server.auth.CASFederateAuth")
+
+    def test_login_get_provider(self):
+        """some assertion about the login page in federated mode"""
+        client = Client()
+        response = client.get("/login")
+        self.assertEqual(response.status_code, 200)
+        for key, value in settings.CAS_FEDERATE_PROVIDERS.items():
+            self.assertTrue('<option value="%s">%s</option>' % (
+                key,
+                utils.get_tuple(value, 2, key)
+            ) in response.content.decode("utf-8"))
+        self.assertEqual(response.context['post_url'], '/federate')
+
+    def test_login_post_provider(self, remember=False):
+        """test a successful login wrokflow"""
+        tickets = []
+        # choose the example.com provider
+        for (provider, cas_port) in [
+            ("example.com", 8080), ("example.org", 8081),
+            ("example.net", 8082), ("example.test", 8083)
+        ]:
+            # get a bare client
+            client = Client()
+            # fetch the login page
+            response = client.get("/login")
+            # in federated mode, we shoudl POST do /federate on the login page
+            self.assertEqual(response.context['post_url'], '/federate')
+            # get current form parameter
+            params = tests_utils.copy_form(response.context["form"])
+            params['provider'] = provider
+            if remember:
+                params['remember'] = 'on'
+            # post the choosed provider
+            response = client.post('/federate', params)
+            # we are redirected to the provider CAS client url
+            self.assertEqual(response.status_code, 302)
+            if remember:
+                self.assertEqual(response["Location"], '%s/federate/%s?remember=on' % (
+                    'http://testserver' if django.VERSION < (1, 9) else "",
+                    provider
+                ))
+            else:
+                self.assertEqual(response["Location"], '%s/federate/%s' % (
+                    'http://testserver' if django.VERSION < (1, 9) else "",
+                    provider
+                ))
+            # let's follow the redirect
+            response = client.get('/federate/%s' % provider)
+            # we are redirected to the provider CAS for authentication
+            self.assertEqual(response.status_code, 302)
+            self.assertEqual(
+                response["Location"],
+                "%s/login?service=http%%3A%%2F%%2Ftestserver%%2Ffederate%%2F%s" % (
+                    settings.CAS_FEDERATE_PROVIDERS[provider][0],
+                    provider
+                )
+            )
+            # let's generate a ticket
+            ticket = utils.gen_st()
+            # we lauch a dummy CAS server that only validate once for the service
+            # http://testserver/federate/example.com with `ticket`
+            tests_utils.DummyCAS.run(
+                ("http://testserver/federate/%s" % provider).encode("ascii"),
+                ticket.encode("ascii"),
+                settings.CAS_TEST_USER.encode("utf8"),
+                [],
+                cas_port
+            )
+            # we normally provide a good ticket and should be redirected to /login as the ticket
+            # get successfully validated again the dummy CAS
+            response = client.get('/federate/%s' % provider, {'ticket': ticket})
+            self.assertEqual(response.status_code, 302)
+            self.assertEqual(response["Location"], "%s/login" % (
+                'http://testserver' if django.VERSION < (1, 9) else ""
+            ))
+            # follow the redirect
+            response = client.get("/login")
+            # we should get a page with a from with all widget hidden that auto POST to /login using
+            # javascript. If javascript is disabled, a "connect" button is showed
+            self.assertTrue(response.context['auto_submit'])
+            self.assertEqual(response.context['post_url'], '/login')
+            params = tests_utils.copy_form(response.context["form"])
+            # POST ge prefiled from parameters
+            response = client.post("/login", params)
+            # the user should now being authenticated using username test@`provider`
+            self.assert_logged(
+                client, response, username='%s@%s' % (settings.CAS_TEST_USER, provider)
+            )
+            tickets.append((provider, ticket, client))
+
+            # try to get a ticket
+            response = client.get("/login", {'service': self.service})
+            self.assertEqual(response.status_code, 302)
+            self.assertTrue(response["Location"].startswith("%s?ticket=" % self.service))
+        return tickets
+
+    def test_login_twice(self):
+        """Test that user id db is used for the second login (cf coverage)"""
+        self.test_login_post_provider()
+        self.test_login_post_provider()
+
+    @override_settings(CAS_FEDERATE=False)
+    def test_auth_federate_false(self):
+        """federated view should redirect to /login then CAS_FEDERATE is False"""
+        provider = "example.com"
+        client = Client()
+        response = client.get("/federate/%s" % provider)
+        self.assertEqual(response.status_code, 302)
+        self.assertEqual(response["Location"], "%s/login" % (
+            'http://testserver' if django.VERSION < (1, 9) else ""
+        ))
+        response = client.post("%s/federate/%s" % (
+            'http://testserver' if django.VERSION < (1, 9) else "",
+            provider
+        ))
+        self.assertEqual(response.status_code, 302)
+        self.assertEqual(response["Location"], "%s/login" % (
+            'http://testserver' if django.VERSION < (1, 9) else ""
+        ))
+
+    def test_auth_federate_errors(self):
+        """
+            The federated view should redirect to /login if the provider is unknown or not provided,
+            try to fetch a new ticket if the provided ticket validation fail
+            (network error or bad ticket)
+        """
+        return
+        good_provider = "example.com"
+        bad_provider = "exemple.fr"
+        client = Client()
+        response = client.get("/federate/%s" % bad_provider)
+        self.assertEqual(response.status_code, 302)
+        self.assertEqual(response["Location"], "%s/login" % (
+            'http://testserver' if django.VERSION < (1, 9) else ""
+        ))
+
+        # test CAS not avaible
+        response = client.get("/federate/%s" % good_provider, {'ticket': utils.gen_st()})
+        self.assertEqual(response.status_code, 302)
+        self.assertEqual(
+            response["Location"],
+            "%s/login?service=http%%3A%%2F%%2Ftestserver%%2Ffederate%%2F%s" % (
+                settings.CAS_FEDERATE_PROVIDERS[good_provider][0],
+                good_provider
+            )
+        )
+
+        # test CAS avaible but bad ticket
+        tests_utils.DummyCAS.run(
+            ("http://testserver/federate/%s" % good_provider).encode("ascii"),
+            utils.gen_st().encode("ascii"),
+            settings.CAS_TEST_USER.encode("utf-8"),
+            [],
+            8080
+        )
+        response = client.get("/federate/%s" % good_provider, {'ticket': utils.gen_st()})
+        self.assertEqual(response.status_code, 302)
+        self.assertEqual(
+            response["Location"],
+            "%s/login?service=http%%3A%%2F%%2Ftestserver%%2Ffederate%%2F%s" % (
+                settings.CAS_FEDERATE_PROVIDERS[good_provider][0],
+                good_provider
+            )
+        )
+
+        response = client.post("/federate")
+        self.assertEqual(response.status_code, 302)
+        self.assertEqual(response["Location"], "%s/login" % (
+            'http://testserver' if django.VERSION < (1, 9) else ""
+        ))
+
+    def test_auth_federate_slo(self):
+        """test that SLO receive from backend CAS log out the users"""
+        # get tickets and connected clients
+        tickets = self.test_login_post_provider()
+        for (provider, ticket, client) in tickets:
+            # SLO for an unkown ticket should do nothing
+            response = client.post(
+                "/federate/%s" % provider,
+                {'logoutRequest': tests_utils.logout_request(utils.gen_st())}
+            )
+            self.assertEqual(response.status_code, 200)
+            self.assertEqual(response.content, b"ok")
+            # Bad SLO format should do nothing
+            response = client.post(
+                "/federate/%s" % provider,
+                {'logoutRequest': ""}
+            )
+            self.assertEqual(response.status_code, 200)
+            self.assertEqual(response.content, b"ok")
+            # Bad SLO format should do nothing
+            response = client.post(
+                "/federate/%s" % provider,
+                {'logoutRequest': "<root></root>"}
+            )
+            self.assertEqual(response.status_code, 200)
+            self.assertEqual(response.content, b"ok")
+            response = client.get("/login")
+            self.assert_logged(
+                client, response, username='%s@%s' % (settings.CAS_TEST_USER, provider)
+            )
+
+            # SLO for a previously logged ticket should log out the user if CAS version is
+            # 3 or 'CAS_2_SAML_1_0'
+            response = client.post(
+                "/federate/%s" % provider,
+                {'logoutRequest': tests_utils.logout_request(ticket)}
+            )
+            self.assertEqual(response.status_code, 200)
+            self.assertEqual(response.content, b"ok")
+
+            response = client.get("/login")
+            if settings.CAS_FEDERATE_PROVIDERS[provider][1] in {3, 'CAS_2_SAML_1_0'}:  # support SLO
+                self.assert_login_failed(client, response)
+            else:
+                self.assert_logged(
+                    client, response, username='%s@%s' % (settings.CAS_TEST_USER, provider)
+                )
+
+    def test_federate_logout(self):
+        """
+            test the logout function: the user should be log out
+            and redirected to his CAS logout page
+        """
+        # get tickets and connected clients
+        tickets = self.test_login_post_provider()
+        for (provider, _, client) in tickets:
+            response = client.get("/logout")
+            self.assertEqual(response.status_code, 302)
+            self.assertEqual(
+                response["Location"],
+                "%s/logout" % settings.CAS_FEDERATE_PROVIDERS[provider][0]
+            )
+            response = client.get("/login")
+            self.assert_login_failed(client, response)
+
+    def test_remember_provider(self):
+        """
+            If the user check remember, next login should not offer the chose of the backend CAS
+            and use the one store in the cookie
+        """
+        tickets = self.test_login_post_provider(remember=True)
+        for (provider, _, client) in tickets:
+            client.get("/logout")
+            response = client.get("/login")
+            self.assertEqual(response.status_code, 302)
+            self.assertEqual(response["Location"], "%s/federate/%s" % (
+                'http://testserver' if django.VERSION < (1, 9) else "",
+                provider
+            ))
+
+    def test_login_bad_ticket(self):
+        """
+            Try login with a bad ticket:
+            login should fail and the main login page should be displayed to the user
+        """
+        provider = "example.com"
+        # get a bare client
+        client = Client()
+        session = client.session
+        session["federate_username"] = '%s@%s' % (settings.CAS_TEST_USER, provider)
+        session["federate_ticket"] = utils.gen_st()
+        try:
+            session.save()
+            response = client.get("/login")
+            # we should get a page with a from with all widget hidden that auto POST to /login using
+            # javascript. If javascript is disabled, a "connect" button is showed
+            self.assertTrue(response.context['auto_submit'])
+            self.assertEqual(response.context['post_url'], '/login')
+            params = tests_utils.copy_form(response.context["form"])
+            # POST, as (username, ticket) are not valid, we should get the federate login page
+            response = client.post("/login", params)
+            self.assertEqual(response.status_code, 200)
+            for key, value in settings.CAS_FEDERATE_PROVIDERS.items():
+                self.assertTrue('<option value="%s">%s</option>' % (
+                    key,
+                    utils.get_tuple(value, 2, key)
+                ) in response.content.decode("utf-8"))
+            self.assertEqual(response.context['post_url'], '/federate')
+        except AttributeError:
+            pass
diff --git a/cas_server/tests/test_models.py b/cas_server/tests/test_models.py
index e75f54f..cdaece8 100644
--- a/cas_server/tests/test_models.py
+++ b/cas_server/tests/test_models.py
@@ -12,20 +12,81 @@
 """Tests module for models"""
 from cas_server.default_settings import settings
 
-from django.test import TestCase
+from django.test import TestCase, Client
 from django.test.utils import override_settings
 from django.utils import timezone
 
 from datetime import timedelta
 from importlib import import_module
 
-from cas_server import models
+from cas_server import models, utils
 from cas_server.tests.utils import get_auth_client, HttpParamsHandler
 from cas_server.tests.mixin import UserModels, BaseServicePattern
 
 SessionStore = import_module(settings.SESSION_ENGINE).SessionStore
 
 
+class FederatedUserTestCase(TestCase, UserModels):
+    """test for the federated user model"""
+    def test_clean_old_entries(self):
+        """tests for clean_old_entries that should delete federated user no longer used"""
+        client = Client()
+        client.get("/login")
+        models.FederatedUser.objects.create(
+            username="test1", provider="example.com", attributs={}, ticket=""
+        )
+        models.FederatedUser.objects.create(
+            username="test2", provider="example.com", attributs={}, ticket=""
+        )
+        models.FederatedUser.objects.all().update(
+            last_update=(timezone.now() - timedelta(seconds=settings.CAS_TICKET_TIMEOUT + 10))
+        )
+        models.FederatedUser.objects.create(
+            username="test3", provider="example.com", attributs={}, ticket=""
+        )
+        models.User.objects.create(
+            username="test1@example.com", session_key=client.session.session_key
+        )
+        models.FederatedUser.clean_old_entries()
+        self.assertEqual(len(models.FederatedUser.objects.all()), 2)
+        with self.assertRaises(models.FederatedUser.DoesNotExist):
+            models.FederatedUser.objects.get(username="test2")
+
+
+class FederateSLOTestCase(TestCase, UserModels):
+    """test for the federated SLO model"""
+    def test_clean_deleted_sessions(self):
+        """
+            tests for clean_deleted_sessions that should delete object for which matching session
+            do not exists anymore
+        """
+        client1 = Client()
+        client2 = Client()
+        client1.get("/login")
+        client2.get("/login")
+        session = client2.session
+        session['authenticated'] = True
+        try:
+            session.save()
+        except AttributeError:
+            pass
+        models.FederateSLO.objects.create(
+            username="test1@example.com",
+            session_key=client1.session.session_key,
+            ticket=utils.gen_st()
+        )
+        models.FederateSLO.objects.create(
+            username="test2@example.com",
+            session_key=client2.session.session_key,
+            ticket=utils.gen_st()
+        )
+        self.assertEqual(len(models.FederateSLO.objects.all()), 2)
+        models.FederateSLO.clean_deleted_sessions()
+        self.assertEqual(len(models.FederateSLO.objects.all()), 1)
+        with self.assertRaises(models.FederateSLO.DoesNotExist):
+            models.FederateSLO.objects.get(username="test1@example.com")
+
+
 @override_settings(CAS_AUTH_CLASS='cas_server.auth.TestAuthUser')
 class UserTestCase(TestCase, UserModels):
     """tests for the user models"""
diff --git a/cas_server/tests/test_utils.py b/cas_server/tests/test_utils.py
index 76fa2cc..411848a 100644
--- a/cas_server/tests/test_utils.py
+++ b/cas_server/tests/test_utils.py
@@ -10,7 +10,7 @@
 #
 # (c) 2016 Valentin Samir
 """Tests module for utils"""
-from django.test import TestCase
+from django.test import TestCase, RequestFactory
 
 import six
 
@@ -189,3 +189,22 @@ class UtilsTestCase(TestCase):
         self.assertFalse(utils.crypt_salt_is_valid("$$"))  # start with $ followed by $
         self.assertFalse(utils.crypt_salt_is_valid("$toto"))  # start with $ but no secondary $
         self.assertFalse(utils.crypt_salt_is_valid("$toto$toto"))  # algorithm toto not known
+
+    def test_get_current_url(self):
+        """test the function get_current_url"""
+        factory = RequestFactory()
+        request = factory.get('/truc/muche?test=1')
+        self.assertEqual(utils.get_current_url(request), 'http://testserver/truc/muche?test=1')
+        self.assertEqual(
+            utils.get_current_url(request, ignore_params={'test'}),
+            'http://testserver/truc/muche'
+        )
+
+    def test_get_tuple(self):
+        """test the function get_tuple"""
+        test_tuple = (1, 2, 3)
+        for index, value in enumerate(test_tuple):
+            self.assertEqual(utils.get_tuple(test_tuple, index), value)
+        self.assertEqual(utils.get_tuple(test_tuple, 3), None)
+        self.assertEqual(utils.get_tuple(test_tuple, 3, 'toto'), 'toto')
+        self.assertEqual(utils.get_tuple(None, 3), None)
diff --git a/cas_server/tests/test_view.py b/cas_server/tests/test_view.py
index 0acd52f..49fa2d2 100644
--- a/cas_server/tests/test_view.py
+++ b/cas_server/tests/test_view.py
@@ -1,4 +1,4 @@
-# ⁻*- coding: utf-8 -*-
+# -*- coding: utf-8 -*-
 # This program is distributed in the hope that it will be useful, but WITHOUT
 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 # FOR A PARTICULAR PURPOSE. See the GNU General Public License version 3 for
@@ -36,57 +36,17 @@ from cas_server.tests.utils import (
     HttpParamsHandler,
     Http404Handler
 )
-from cas_server.tests.mixin import BaseServicePattern, XmlContent
+from cas_server.tests.mixin import BaseServicePattern, XmlContent, CanLogin
 
 
 @override_settings(CAS_AUTH_CLASS='cas_server.auth.TestAuthUser')
-class LoginTestCase(TestCase, BaseServicePattern):
+class LoginTestCase(TestCase, BaseServicePattern, CanLogin):
     """Tests for the login view"""
     def setUp(self):
         """Prepare the test context:"""
         # we prepare a bunch a service url and service patterns for tests
         self.setup_service_patterns()
 
-    def assert_logged(self, client, response, warn=False, code=200):
-        """Assertions testing that client is well authenticated"""
-        self.assertEqual(response.status_code, code)
-        # this message is displayed to the user upon successful authentication
-        self.assertTrue(
-            (
-                b"You have successfully logged into "
-                b"the Central Authentication Service"
-            ) in response.content
-        )
-        # these session variables a set if usccessfully authenticated
-        self.assertTrue(client.session["username"] == settings.CAS_TEST_USER)
-        self.assertTrue(client.session["warn"] is warn)
-        self.assertTrue(client.session["authenticated"] is True)
-
-        # on successfull authentication, a corresponding user object is created
-        self.assertTrue(
-            models.User.objects.get(
-                username=settings.CAS_TEST_USER,
-                session_key=client.session.session_key
-            )
-        )
-
-    def assert_login_failed(self, client, response, code=200):
-        """Assertions testing a failed login attempt"""
-        self.assertEqual(response.status_code, code)
-        # this message is displayed to the user upon successful authentication, so it should not
-        # appear
-        self.assertFalse(
-            (
-                b"You have successfully logged into "
-                b"the Central Authentication Service"
-            ) in response.content
-        )
-
-        # if authentication has failed, these session variables should not be set
-        self.assertTrue(client.session.get("username") is None)
-        self.assertTrue(client.session.get("warn") is None)
-        self.assertTrue(client.session.get("authenticated") is None)
-
     def test_login_view_post_goodpass_goodlt(self):
         """Test a successul login"""
         # we get a client who fetch a frist time the login page and the login form default
diff --git a/cas_server/tests/utils.py b/cas_server/tests/utils.py
index bd692e9..b8419c6 100644
--- a/cas_server/tests/utils.py
+++ b/cas_server/tests/utils.py
@@ -13,14 +13,33 @@
 from cas_server.default_settings import settings
 
 from django.test import Client
+from django.template import loader, Context
+from django.utils import timezone
 
 import cgi
+import six
 from threading import Thread
 from lxml import etree
 from six.moves import BaseHTTPServer
 from six.moves.urllib.parse import urlparse, parse_qsl
+from datetime import timedelta
 
 from cas_server import models
+from cas_server import utils
+
+
+def return_unicode(string, charset):
+    if not isinstance(string, six.text_type):
+        return string.decode(charset)
+    else:
+        return string
+
+
+def return_bytes(string, charset):
+    if isinstance(string, six.text_type):
+        return string.encode(charset)
+    else:
+        return string
 
 
 def copy_form(form):
@@ -149,10 +168,10 @@ class HttpParamsHandler(BaseHTTPServer.BaseHTTPRequestHandler):
         return
 
     @classmethod
-    def run(cls):
+    def run(cls, port=0):
         """Run a BaseHTTPServer using this class as handler"""
         server_class = BaseHTTPServer.HTTPServer
-        httpd = server_class(("127.0.0.1", 0), cls)
+        httpd = server_class(("127.0.0.1", port), cls)
         (host, port) = httpd.socket.getsockname()
 
         def lauch():
@@ -178,3 +197,143 @@ class Http404Handler(HttpParamsHandler):
     def do_POST(self):
         """Called on a POST request on the BaseHTTPServer"""
         return self.do_GET()
+
+
+class DummyCAS(BaseHTTPServer.BaseHTTPRequestHandler):
+
+    def test_params(self):
+        if (
+            self.server.ticket is not None and
+            self.params.get("service").encode("ascii") == self.server.service and
+            self.params.get("ticket").encode("ascii") == self.server.ticket
+        ):
+            self.server.ticket = None
+            print("good")
+            return True
+        else:
+            print("bad (%r, %r) != (%r, %r)" % (
+                self.params.get("service").encode("ascii"),
+                self.params.get("ticket").encode("ascii"),
+                self.server.service,
+                self.server.ticket
+            ))
+
+            return False
+
+    def send_headers(self, code, content_type):
+        self.send_response(200)
+        self.send_header("Content-type", content_type)
+        self.end_headers()
+
+    def do_GET(self):
+        url = urlparse(self.path)
+        self.params = dict(parse_qsl(url.query))
+        if url.path == "/validate":
+            self.send_headers(200, "text/plain; charset=utf-8")
+            if self.test_params():
+                self.wfile.write(b"yes\n" + self.server.username + b"\n")
+                self.server.ticket = None
+            else:
+                self.wfile.write(b"no\n")
+        elif url.path in {
+            '/serviceValidate', '/serviceValidate',
+            '/p3/serviceValidate', '/p3/proxyValidate'
+        }:
+            self.send_headers(200, "text/xml; charset=utf-8")
+            if self.test_params():
+                t = loader.get_template('cas_server/serviceValidate.xml')
+                c = Context({
+                    'username': self.server.username,
+                    'attributes': self.server.attributes
+                })
+                self.wfile.write(return_bytes(t.render(c), "utf8"))
+            else:
+                t = loader.get_template('cas_server/serviceValidateError.xml')
+                c = Context({
+                    'code': 'BAD_SERVICE_TICKET',
+                    'msg': 'Valids are (%r, %r)' % (self.server.service, self.server.ticket)
+                })
+                self.wfile.write(return_bytes(t.render(c), "utf8"))
+        else:
+            self.return_404()
+
+    def do_POST(self):
+        url = urlparse(self.path)
+        self.params = dict(parse_qsl(url.query))
+        if url.path == "/samlValidate":
+            self.send_headers(200, "text/xml; charset=utf-8")
+            length = int(self.headers.get('content-length'))
+            root = etree.fromstring(self.rfile.read(length))
+            auth_req = root.getchildren()[1].getchildren()[0]
+            ticket = auth_req.getchildren()[0].text.encode("ascii")
+            if (
+                self.server.ticket is not None and
+                self.params.get("TARGET").encode("ascii") == self.server.service and
+                ticket == self.server.ticket
+            ):
+                self.server.ticket = None
+                t = loader.get_template('cas_server/samlValidate.xml')
+                c = Context({
+                    'IssueInstant': timezone.now().isoformat(),
+                    'expireInstant': (timezone.now() + timedelta(seconds=60)).isoformat(),
+                    'Recipient': self.server.service,
+                    'ResponseID': utils.gen_saml_id(),
+                    'username': self.server.username,
+                    'attributes': self.server.attributes,
+                })
+                self.wfile.write(return_bytes(t.render(c), "utf8"))
+            else:
+                t = loader.get_template('cas_server/samlValidateError.xml')
+                c = Context({
+                    'IssueInstant': timezone.now().isoformat(),
+                    'ResponseID': utils.gen_saml_id(),
+                    'code': 'BAD_SERVICE_TICKET',
+                    'msg': 'Valids are (%r, %r)' % (self.server.service, self.server.ticket)
+                })
+                self.wfile.write(return_bytes(t.render(c), "utf8"))
+        else:
+            self.return_404()
+
+    def return_404(self):
+            self.send_response(404)
+            self.send_header(b"Content-type", "text/plain")
+            self.end_headers()
+            self.wfile.write("not found")
+
+    def log_message(self, *args):
+        """silent any log message"""
+        return
+
+    @classmethod
+    def run(cls, service, ticket, username, attributes, port=0):
+        """Run a BaseHTTPServer using this class as handler"""
+        server_class = BaseHTTPServer.HTTPServer
+        httpd = server_class(("127.0.0.1", port), cls)
+        httpd.service = service
+        httpd.ticket = ticket
+        httpd.username = username
+        httpd.attributes = attributes
+        (host, port) = httpd.socket.getsockname()
+
+        def lauch():
+            """routine to lauch in a background thread"""
+            httpd.handle_request()
+            httpd.server_close()
+
+        httpd_thread = Thread(target=lauch)
+        httpd_thread.daemon = True
+        httpd_thread.start()
+        return (httpd, host, port)
+
+
+def logout_request(ticket):
+    return u"""<samlp:LogoutRequest xmlns:samlp="urn:oasis:names:tc:SAML:2.0:protocol"
+ ID="%(id)s" Version="2.0" IssueInstant="%(datetime)s">
+<saml:NameID xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion"></saml:NameID>
+<samlp:SessionIndex>%(ticket)s</samlp:SessionIndex>
+</samlp:LogoutRequest>""" % \
+        {
+            'id': utils.gen_saml_id(),
+            'datetime': timezone.now().isoformat(),
+            'ticket':  ticket
+        }
diff --git a/cas_server/views.py b/cas_server/views.py
index 9543c6f..05ce47d 100644
--- a/cas_server/views.py
+++ b/cas_server/views.py
@@ -123,15 +123,18 @@ class LogoutView(View, LogoutMixin):
         self.init_get(request)
         # if CAS federation mode is enable, bakup the provider before flushing the sessions
         if settings.CAS_FEDERATE:
-            component = self.request.session.get("username").split('@')
-            provider = component[-1]
-            auth = CASFederateValidateUser(provider, service_url="")
+            if "username" in self.request.session:
+                component = self.request.session["username"].split('@')
+                provider = component[-1]
+                auth = CASFederateValidateUser(provider, service_url="")
+            else:
+                auth = None
         session_nb = self.logout(self.request.GET.get("all"))
         # if CAS federation mode is enable, redirect to user CAS logout page
         if settings.CAS_FEDERATE:
-            params = utils.copy_params(request.GET)
-            url = utils.update_url(auth.get_logout_url(), params)
-            if url:
+            if auth is not None:
+                params = utils.copy_params(request.GET)
+                url = utils.update_url(auth.get_logout_url(), params)
                 return HttpResponseRedirect(url)
         # if service is set, redirect to service after logout
         if self.service:
@@ -195,7 +198,7 @@ class FederateAuth(View):
 
     @staticmethod
     def get_cas_client(request, provider):
-        if provider in settings.CAS_FEDERATE_PROVIDERS:
+        if provider in settings.CAS_FEDERATE_PROVIDERS:  # pragma: no branch (should always be true)
             service_url = utils.get_current_url(request, {"ticket", "provider"})
             return CASFederateValidateUser(provider, service_url)
 
@@ -207,14 +210,14 @@ class FederateAuth(View):
             auth = self.get_cas_client(request, provider)
             try:
                 auth.clean_sessions(request.POST['logoutRequest'])
-            except KeyError:
+            except (KeyError, AttributeError):
                 pass
             return HttpResponse("ok")
         # else, a User is trying to log in using an identity provider
         else:
             # Manually checking for csrf to protect the code below
             reason = CsrfViewMiddleware().process_view(request, None, (), {})
-            if reason is not None:
+            if reason is not None:  # pragma: no cover (csrf checks are disabled during tests)
                 return reason  # Failed the test, stop here.
             form = forms.FederateSelect(request.POST)
             if form.is_valid():
@@ -252,7 +255,7 @@ class FederateAuth(View):
             ticket = request.GET['ticket']
             if auth.verify_ticket(ticket):
                 params = utils.copy_params(request.GET, ignore={"ticket"})
-                username = "%s@%s" % (auth.username, auth.provider)
+                username = u"%s@%s" % (auth.username, auth.provider)
                 request.session["federate_username"] = username
                 request.session["federate_ticket"] = ticket
                 auth.register_slo(username, request.session.session_key, ticket)
@@ -281,9 +284,9 @@ class LoginView(View, LogoutMixin):
     renewed = False
     warned = False
 
-    if settings.CAS_FEDERATE:
-        username = None
-        ticket = None
+    # used if CAS_FEDERATE is True
+    username = None
+    ticket = None
 
     INVALID_LOGIN_TICKET = 1
     USER_LOGIN_OK = 2
@@ -354,7 +357,7 @@ class LoginView(View, LogoutMixin):
         elif ret == self.USER_LOGIN_FAILURE:  # bad user login
             if settings.CAS_FEDERATE:
                 self.ticket = None
-                self.usernalme = None
+                self.username = None
                 self.init_form()
             self.logout()
         elif ret == self.USER_ALREADY_LOGGED:
@@ -682,11 +685,14 @@ class Auth(View):
         secret = request.POST.get('secret')
 
         if not settings.CAS_AUTH_SHARED_SECRET:
-            return HttpResponse("no\nplease set CAS_AUTH_SHARED_SECRET", content_type="text/plain")
+            return HttpResponse(
+                "no\nplease set CAS_AUTH_SHARED_SECRET",
+                content_type="text/plain; charset=utf-8"
+            )
         if secret != settings.CAS_AUTH_SHARED_SECRET:
-            return HttpResponse("no\n", content_type="text/plain")
+            return HttpResponse(u"no\n", content_type="text/plain; charset=utf-8")
         if not username or not password or not service:
-            return HttpResponse("no\n", content_type="text/plain")
+            return HttpResponse(u"no\n", content_type="text/plain; charset=utf-8")
         form = forms.UserCredential(
             request.POST,
             initial={
@@ -714,11 +720,11 @@ class Auth(View):
                 service_pattern.check_user(user)
                 if not request.session.get("authenticated"):
                     user.delete()
-                return HttpResponse("yes\n", content_type="text/plain")
+                return HttpResponse(u"yes\n", content_type="text/plain; charset=utf-8")
             except (ServicePattern.DoesNotExist, models.ServicePatternException):
-                return HttpResponse("no\n", content_type="text/plain")
+                return HttpResponse(u"no\n", content_type="text/plain; charset=utf-8")
         else:
-            return HttpResponse("no\n", content_type="text/plain")
+            return HttpResponse(u"no\n", content_type="text/plain; charset=utf-8")
 
 
 class Validate(View):
@@ -758,7 +764,10 @@ class Validate(View):
                         username = username[0]
                 else:
                     username = ticket.user.username
-                return HttpResponse("yes\n%s\n" % username, content_type="text/plain")
+                return HttpResponse(
+                    u"yes\n%s\n" % username,
+                    content_type="text/plain; charset=utf-8"
+                )
             except ServiceTicket.DoesNotExist:
                 logger.warning(
                     (
@@ -769,10 +778,10 @@ class Validate(View):
                         service
                     )
                 )
-                return HttpResponse("no\n", content_type="text/plain")
+                return HttpResponse(u"no\n", content_type="text/plain; charset=utf-8")
         else:
             logger.warning("Validate: service or ticket missing")
-            return HttpResponse("no\n", content_type="text/plain")
+            return HttpResponse(u"no\n", content_type="text/plain; charset=utf-8")
 
 
 class ValidateError(Exception):
@@ -815,8 +824,8 @@ class ValidateService(View, AttributesMixin):
         if not self.service or not self.ticket:
             logger.warning("ValidateService: missing ticket or service")
             return ValidateError(
-                'INVALID_REQUEST',
-                "you must specify a service and a ticket"
+                u'INVALID_REQUEST',
+                u"you must specify a service and a ticket"
             ).render(request)
         else:
             try:
@@ -886,14 +895,14 @@ class ValidateService(View, AttributesMixin):
                 for prox in ticket.proxies.all():
                     proxies.append(prox.url)
             else:
-                raise ValidateError('INVALID_TICKET', self.ticket)
+                raise ValidateError(u'INVALID_TICKET', self.ticket)
             ticket.validate = True
             ticket.save()
             if ticket.service != self.service:
-                raise ValidateError('INVALID_SERVICE', self.service)
+                raise ValidateError(u'INVALID_SERVICE', self.service)
             return ticket, proxies
         except (ServiceTicket.DoesNotExist, ProxyTicket.DoesNotExist):
-            raise ValidateError('INVALID_TICKET', 'ticket not found')
+            raise ValidateError(u'INVALID_TICKET', 'ticket not found')
 
     def process_pgturl(self, params):
         """Handle PGT request"""
@@ -939,18 +948,18 @@ class ValidateService(View, AttributesMixin):
                 except requests.exceptions.RequestException as error:
                     error = utils.unpack_nested_exception(error)
                     raise ValidateError(
-                        'INVALID_PROXY_CALLBACK',
-                        "%s: %s" % (type(error), str(error))
+                        u'INVALID_PROXY_CALLBACK',
+                        u"%s: %s" % (type(error), str(error))
                     )
             else:
                 raise ValidateError(
-                    'INVALID_PROXY_CALLBACK',
-                    "callback url not allowed by configuration"
+                    u'INVALID_PROXY_CALLBACK',
+                    u"callback url not allowed by configuration"
                 )
         except ServicePattern.DoesNotExist:
             raise ValidateError(
-                'INVALID_PROXY_CALLBACK',
-                'callback url not allowed by configuration'
+                u'INVALID_PROXY_CALLBACK',
+                u'callback url not allowed by configuration'
             )
 
 
@@ -971,8 +980,8 @@ class Proxy(View):
                 return self.process_proxy()
             else:
                 raise ValidateError(
-                    'INVALID_REQUEST',
-                    "you must specify and pgt and targetService"
+                    u'INVALID_REQUEST',
+                    u"you must specify and pgt and targetService"
                 )
         except ValidateError as error:
             logger.warning("Proxy: validation error: %s %s" % (error.code, error.msg))
@@ -985,8 +994,8 @@ class Proxy(View):
             pattern = ServicePattern.validate(self.target_service)
             if not pattern.proxy:
                 raise ValidateError(
-                    'UNAUTHORIZED_SERVICE',
-                    'the service %s do not allow proxy ticket' % self.target_service
+                    u'UNAUTHORIZED_SERVICE',
+                    u'the service %s do not allow proxy ticket' % self.target_service
                 )
             # is the proxy granting ticket valid
             ticket = ProxyGrantingTicket.objects.get(
@@ -1015,13 +1024,13 @@ class Proxy(View):
                 content_type="text/xml; charset=utf-8"
             )
         except ProxyGrantingTicket.DoesNotExist:
-            raise ValidateError('INVALID_TICKET', 'PGT %s not found' % self.pgt)
+            raise ValidateError(u'INVALID_TICKET', u'PGT %s not found' % self.pgt)
         except ServicePattern.DoesNotExist:
-            raise ValidateError('UNAUTHORIZED_SERVICE', self.target_service)
+            raise ValidateError(u'UNAUTHORIZED_SERVICE', self.target_service)
         except (models.BadUsername, models.BadFilter, models.UserFieldNotDefined):
             raise ValidateError(
-                'UNAUTHORIZED_USER',
-                'User %s not allowed on %s' % (ticket.user.username, self.target_service)
+                u'UNAUTHORIZED_USER',
+                u'User %s not allowed on %s' % (ticket.user.username, self.target_service)
             )
 
 
@@ -1129,18 +1138,18 @@ class SamlValidate(View, AttributesMixin):
                 )
             else:
                 raise SamlValidateError(
-                    'AuthnFailed',
-                    'ticket %s should begin with PT- or ST-' % ticket
+                    u'AuthnFailed',
+                    u'ticket %s should begin with PT- or ST-' % ticket
                 )
             ticket.validate = True
             ticket.save()
             if ticket.service != self.target:
                 raise SamlValidateError(
-                    'AuthnFailed',
-                    'TARGET %s do not match ticket service' % self.target
+                    u'AuthnFailed',
+                    u'TARGET %s do not match ticket service' % self.target
                 )
             return ticket
         except (IndexError, KeyError):
-            raise SamlValidateError('VersionMismatch')
+            raise SamlValidateError(u'VersionMismatch')
         except (ServiceTicket.DoesNotExist, ProxyTicket.DoesNotExist):
-            raise SamlValidateError('AuthnFailed', 'ticket %s not found' % ticket)
+            raise SamlValidateError(u'AuthnFailed', u'ticket %s not found' % ticket)