Added logic to validate the default values from the templates.

Incorporated the review comments and added unit testcase for the newly added
method.

Co-Authored-By: Sahdev Zala <spzala@us.ibm.com>

Related-bug: #1567552

Change-Id: I41f574a353495f25957b9b25ce6368fe6e92dbc2

toscaparser/parameters.py

@@ -53,7 +53,7 @@ class Input(object):
     def validate(self, value=None):
         self._validate_field()
         self.validate_type(self.type)
-        if value:
+        if value is not None:
             self._validate_value(value)
 
     def _validate_field(self):

toscaparser/tests/data/test_invalid_input_defaults.yaml

@@ -0,0 +1,12 @@
+tosca_definitions_version: tosca_simple_yaml_1_0
+
+description: Test template with default not matching required type.
+
+topology_template:
+  inputs:
+    invalid_default:
+      type: integer
+      default: two
+    valid_default:
+      type: integer
+      default: 2

toscaparser/tests/test_toscatplvalidation.py

@@ -1385,3 +1385,11 @@ heat-translator/master/translator/tests/data/custom_types/wordpress.yaml
             os.path.dirname(os.path.abspath(__file__)),
             "data/test_credential_datatype.yaml")
         self.assertIsNotNone(ToscaTemplate(tosca_tpl))
+
+    def test_invalid_default_value(self):
+        tpl_path = os.path.join(
+            os.path.dirname(os.path.abspath(__file__)),
+            "data/test_invalid_input_defaults.yaml")
+        self.assertRaises(exception.ValidationError, ToscaTemplate, tpl_path)
+        exception.ExceptionCollector.assertExceptionMessage(
+            ValueError, _('"two" is not an integer.'))

toscaparser/topology_template.py

@@ -65,6 +65,10 @@ class TopologyTemplate(object):
             input = Input(name, attrs)
             if self.parsed_params and name in self.parsed_params:
                 input.validate(self.parsed_params[name])
+            else:
+                default = input.default
+                if default:
+                    input.validate(default)
             inputs.append(input)
         return inputs