admin: fix encoding handling in remote idp metadata update (#45269)

tests/test_admin_pages.py

@@ -5076,7 +5076,7 @@ def test_settings_idp(pub):
 
     with mock.patch('wcs.qommon.misc.urlopen') as urlopen:
         idp_metadata_filename = os.path.join(os.path.dirname(__file__), 'idp_metadata.xml')
-        urlopen.side_effect = lambda *args: open(idp_metadata_filename)
+        urlopen.side_effect = lambda *args: open(idp_metadata_filename, 'rb')
         resp = app.get('/backoffice/settings/identification/idp/idp/')
         resp = resp.click('Create new from remote URL')
         resp.form['metadata_url'] = 'http://authentic.example.net/idp/saml2/metadata'

wcs/qommon/ident/idp.py

@@ -14,12 +14,14 @@
 # You should have received a copy of the GNU General Public License
 # along with this program; if not, see <http://www.gnu.org/licenses/>.
 
+import re
+
 try:
     import lasso
 except ImportError:
     lasso = None
 
-from django.utils.encoding import force_bytes
+from django.utils.encoding import force_bytes, force_text
 from django.utils.six.moves.urllib import parse as urllib
 from django.utils.six.moves.urllib import parse as urlparse
 
@@ -655,7 +657,7 @@ class AdminIDPUI(Directory):
             metadata_fd = misc.urlopen(metadata_url)
         except misc.ConnectionError:
             return template.error_page('failed to download')
-        metadata = metadata_fd.read()
+        metadata = force_text(metadata_fd.read())
 
         publickey_url = self.idp.get('publickey_url')
         if publickey_url: