Add parameter type validation before stack-create

If a number parameter accept a string that can't convert to number,
it will break heat functions and heat cli can't get any stack
information but a ValuerError message.
Add Number and Boolean parameter type validation before stack
create, so we can avoid above situation.

Change-Id: I25a41543027f929201a9b053d123d8e2b16e2725
Closes-Bug: #1329152

heat/engine/parameters.py

@@ -278,6 +278,10 @@ def __float__(self):
         return float(super(NumberParam, self).value())
 
     def _validate(self, val, context):
+        try:
+            Schema.str_to_num(val)
+        except ValueError as ex:
+            raise exception.StackValidationFailed(message=six.text_type(ex))
         self.schema.validate_value(self.name, val, context)
 
     def value(self):
@@ -288,6 +292,10 @@ class BooleanParam(Parameter):
     '''A template parameter of type "Boolean".'''
 
     def _validate(self, val, context):
+        try:
+            strutils.bool_from_string(val, strict=True)
+        except ValueError as ex:
+            raise exception.StackValidationFailed(message=six.text_type(ex))
         self.schema.validate_value(self.name, val, context)
 
     def value(self):

heat/tests/test_parameters.py

@@ -210,6 +210,12 @@ def test_number_high(self):
                                 self.new_parameter, 'p', schema, '3')
         self.assertIn('wibble', str(err))
 
+    def test_number_bad(self):
+        schema = {'Type': 'Number'}
+        err = self.assertRaises(exception.StackValidationFailed,
+                                self.new_parameter, 'p', schema, 'str')
+        self.assertIn('float', str(err))
+
     def test_number_value_list_good(self):
         schema = {'Type': 'Number',
                   'AllowedValues': ['1', '3', '5']}
@@ -318,8 +324,8 @@ def test_bool_value_false(self):
 
     def test_bool_value_invalid(self):
         schema = {'Type': 'Boolean'}
-        bo = self.new_parameter('bo', schema, 'foo')
-        err = self.assertRaises(ValueError, bo.value)
+        err = self.assertRaises(exception.StackValidationFailed,
+                                self.new_parameter, 'bo', schema, 'foo')
         self.assertIn("Unrecognized value 'foo'", unicode(err))
 
     def test_missing_param(self):