[16.0][DOC] add documentation for safe_ldap_decode()

Author: oh2fih

users_ldap_groups/models/res_company_ldap_operator.py

@@ -45,6 +45,13 @@ def _query(self, ldap_entry, mapping):
         return bool(results)
 
     def safe_ldap_decode(self, attr):
+        """Safe LDAP decode; Base64 encode attributes containing binary data.
+        Binary data can be stored in Active Directory, e.g., thumbnailPhoto is
+        stored as binary. As Str.decoce() cannot handle binary, this method
+        Base64 encodes the data in the attribute, instead, if decode fails.
+        Using Base64 should be a suitable fallback, because the use cases of
+        users_ldap_groups do not really require comparing binary attributes.
+        """
         try:
             return attr.decode()
         except UnicodeDecodeError: