Add logging for requests.

Author: Alexander Schrijver

src/onelogin/saml2/auth.py

@@ -11,8 +11,10 @@
 
 """
 
+import logging
 import xmlsec
 
+
 from onelogin.saml2 import compat
 from onelogin.saml2.authn_request import OneLogin_Saml2_Authn_Request
 from onelogin.saml2.constants import OneLogin_Saml2_Constants
@@ -24,6 +26,9 @@
 from onelogin.saml2.xmlparser import tostring
 
 
+logger = logging.getLogger(__name__)
+
+
 class OneLogin_Saml2_Auth(object):
     """
 
@@ -389,22 +394,29 @@ def _create_authn_request(
 
     def login_post(self, return_to=None, **authn_kwargs):
         authn_request = self._create_authn_request(**authn_kwargs)
+
+        url = self.get_sso_url()
+        data = authn_request.get_request(deflate=False, base64_encode=False)
         saml_request = OneLogin_Saml2_Utils.b64encode(
             OneLogin_Saml2_Utils.add_sign(
-                authn_request.get_request(deflate=False, base64_encode=False),
+                data,
                 self.__settings.get_sp_key(), self.__settings.get_sp_cert(),
                 sign_algorithm=OneLogin_Saml2_Constants.RSA_SHA256,
                 digest_algorithm=OneLogin_Saml2_Constants.SHA256,),
 
         )
+        logger.debug(
+            "Returning form-data to the user for a AuthNRequest to %s with SAMLRequest %s",
+            url, OneLogin_Saml2_Utils.b64decode(saml_request).decode('utf-8')
+        )
         parameters = {'SAMLRequest': saml_request}
 
         if return_to is not None:
             parameters['RelayState'] = return_to
         else:
             parameters['RelayState'] = OneLogin_Saml2_Utils.get_self_url_no_query(self.__request_data)
 
-        return self.get_sso_url(), parameters
+        return url, parameters
 
     def login(self, return_to=None, **authn_kwargs):
         """