'Nullable' attributes are correctly parsed and reviewed.

Changes:
- Consistent way of parsing bool attributes
- Supports 'Nullable' attribute for properties (default: True)
- Supports 'Nullable' attribute for function import parameters (default: False)

Issue: #98

Author: Vasilii Khomutov

CHANGELOG.md

@@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Fixed
 - removed superfluous debug print when parsing FunctionImports from metadata - Jakub Filak
+- property 'Nullable' attributes are correctly parsed and respected - Vasilii Khomutov
 
 ## [1.4.0]
 

pyodata/v2/model.py

@@ -1668,7 +1668,7 @@ def from_etree(entity_type_property_node):
         return StructTypeProperty(
             entity_type_property_node.get('Name'),
             Types.parse_type_name(entity_type_property_node.get('Type')),
-            entity_type_property_node.get('Nullable'),
+            attribute_get_bool(entity_type_property_node, 'Nullable', True),
             entity_type_property_node.get('MaxLength'),
             entity_type_property_node.get('Precision'),
             entity_type_property_node.get('Scale'),
@@ -2364,7 +2364,7 @@ def from_etree(function_import_node, config: Config):
         for param in function_import_node.xpath('edm:Parameter', namespaces=config.namespaces):
             param_name = param.get('Name')
             param_type_info = Types.parse_type_name(param.get('Type'))
-            param_nullable = param.get('Nullable')
+            param_nullable = attribute_get_bool(param, 'Nullable', False)
             param_max_length = param.get('MaxLength')
             param_precision = param.get('Precision')
             param_scale = param.get('Scale')
@@ -2401,8 +2401,7 @@ def sap_attribute_get_string(node, attr):
     return sap_attribute_get(node, attr)
 
 
-def sap_attribute_get_bool(node, attr, default):
-    value = sap_attribute_get(node, attr)
+def str_to_bool(value, attr, default):
     if value is None:
         return default
 
@@ -2415,6 +2414,14 @@ def sap_attribute_get_bool(node, attr, default):
     raise TypeError('Not a bool attribute: {0} = {1}'.format(attr, value))
 
 
+def attribute_get_bool(node, attr, default):
+    return str_to_bool(node.get(attr), attr, default)
+
+
+def sap_attribute_get_bool(node, attr, default):
+    return str_to_bool(sap_attribute_get(node, attr), attr, default)
+
+
 ANNOTATION_NAMESPACES = {
     'edm': 'http://docs.oasis-open.org/odata/ns/edm',
     'edmx': 'http://docs.oasis-open.org/odata/ns/edmx'

tests/metadata.xml

@@ -303,6 +303,7 @@
                 <Property Name="ID" Type="Edm.Int32" Nullable="false"/>
                 <Property Name="NameFirst" Type="Edm.String" Nullable="true"/>
                 <Property Name="NameLast" Type="Edm.String" Nullable="true"/>
+                <Property Name="NickName" Type="Edm.String"/>
                 <NavigationProperty Name="Addresses" Relationship="EXAMPLE_SRV_SETS.AssociationEmployeeAddress"
                                     FromRole="EmployeeRole" ToRole="AddressRole"/>
             </EntityType>

tests/test_model_v2.py

@@ -147,6 +147,19 @@ def test_edmx(schema):
     assert typ_ex_info.value.args[0] == 'Type FooBar does not exist in Schema Namespace EXAMPLE_SRV'
 
 
+def test_schema_entity_type_nullable(schema):
+    emp_entity = schema.entity_type('Employee')
+
+    id_property = emp_entity.proprty('ID')
+    assert not id_property.nullable
+
+    firstname_property = emp_entity.proprty('NameFirst')
+    assert firstname_property.nullable
+
+    nickname_property = emp_entity.proprty('NickName')
+    assert nickname_property.nullable
+
+
 def test_schema_entity_sets(schema):
     """Test Schema methods for EntitySets"""