[_708] new __slots__ members to prevent configuration miswrites

irods/client_configuration/__init__.py

@@ -45,6 +45,8 @@ def __new__(meta, name, bases, attrs):
 
 
 class ConnectionsProperties(iRODSConfiguration, metaclass=iRODSConfigAliasMetaclass):
+    __slots__ = ()
+
     @property
     def xml_parser_default(self):
         from irods.message import get_default_XML_by_name
@@ -59,10 +61,13 @@ def xml_parser_default(self, str_value):
 
 connections = ConnectionsProperties()
 
+
 class ConfigurationError(BaseException): pass
 class ConfigurationValueError(ValueError,ConfigurationError): pass
 
+
 class Genquery1_Properties(iRODSConfiguration, metaclass=iRODSConfigAliasMetaclass):
+    __slots__ = ()
 
     @property
     def irods_query_limit(self):
@@ -89,6 +94,7 @@ def irods_query_limit(self, target_value):
 
 
 class DataObjects(iRODSConfiguration):
+
     __slots__ = (
         "auto_close",
         "allow_redirect",

irods/test/client_configuration_test.py

@@ -0,0 +1,43 @@
+import unittest
+
+import irods.client_configuration as cfg
+
+
+# Test assignments on the negative and positive space of the
+# client configuration.
+class TestClientConfigurationAttributes(unittest.TestCase):
+    def test_configuration_writes_and_miswrites__issue_708(self):
+        # For caching configuration objects
+        configuration_level = {}
+        leaf_names = []
+
+        for dotted_name, value, is_conf in cfg._var_items_as_generator():  # noqa: SLF001
+            with self.subTest(dotted_name=dotted_name):
+                name_parts = dotted_name.split('.')
+                namespace = '.'.join(name_parts[:-1])
+                attribute_name = name_parts[-1]
+                if isinstance(value, cfg.iRODSConfiguration):
+                    # Store a parent object corresponding to a namespace.  For any leaf value 
+                    # subsequently found in the top-down descent, to be sitting directly within
+                    # that namespace, the "else is_conf" part of this if/else will run the core
+                    # part of the test on the corresponding configuration setting.
+                    configuration_level[dotted_name] = value
+                elif is_conf:
+                    # A configuration setting was actually found (i.e. a "leaf" value within a dotted name.)
+
+                    # Store the leaf name for proof positive of subtests actually run.
+                    leaf_names.append(attribute_name)
+
+                    # Test the positive space, i.e. the 'hit'.  This simply tests that the
+                    # setting may be written to without error:
+                    setattr(configuration_level[namespace], attribute_name, value)
+
+                    # Test the negative space, i.e. a deliberate 'miss'.  This time we must fail;
+                    # otherwise we'd get a silent miswrite in the form of a write to the incorrect attribute.
+                    # (The new __slots__ members are there to prevent this):
+                    with self.assertRaises(AttributeError):
+                        setattr(configuration_level[namespace], attribute_name + '_1', value)
+
+        # These cases were identified as likely ones for possible failed writes via misspelling.
+        self.assertIn('irods_query_limit', leaf_names)
+        self.assertIn('xml_parser_default', leaf_names)