Validation of imported templates

Validated First level sections of imported templates,First level
sub-sections of node_types and policy_types
and added testcases for the same

Change-Id: I51f4e2496fea567fb0e5672f77899334c7556909
Partially Implements: #1516177

toscaparser/elements/tosca_type_validation.py

@@ -0,0 +1,59 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from toscaparser.common.exception import ExceptionCollector
+from toscaparser.common.exception import InvalidTemplateVersion
+from toscaparser.common.exception import UnknownFieldError
+from toscaparser.extensions.exttools import ExtTools
+
+
+class TypeValidation(object):
+
+    ALLOWED_TYPE_SECTIONS = (DEFINITION_VERSION, DESCRIPTION, IMPORTS,
+                             DSL_DEFINITIONS, NODE_TYPES, REPOSITORIES,
+                             DATA_TYPES, ARTIFACT_TYPES, GROUP_TYPES,
+                             RELATIONSHIP_TYPES, CAPABILITY_TYPES,
+                             INTERFCAE_TYPES, POLICY_TYPES, DATATYPE_DEFINITIONS) = \
+        ('tosca_definitions_version', 'description',
+         'imports', 'dsl_definitions', 'node_types',
+         'repositories', 'data_types', 'group_types',
+         'artifact_types', 'relationship_types',
+         'capability_types', 'interface_types',
+         'policy_types', 'datatype_definitions')
+    VALID_TEMPLATE_VERSIONS = ['tosca_simple_yaml_1_0']
+    exttools = ExtTools()
+    VALID_TEMPLATE_VERSIONS.extend(exttools.get_versions())
+
+    def __init__(self, custom_types, import_def):
+        self.import_def = import_def
+        self._validate_type_keys(custom_types)
+
+    def _validate_type_keys(self, custom_type):
+        version = custom_type[self.DEFINITION_VERSION] \
+            if self.DEFINITION_VERSION in custom_type \
+            else None
+        if version:
+            self._validate_type_version(version)
+            self.version = version
+
+        for name in custom_type:
+            if name not in self.ALLOWED_TYPE_SECTIONS:
+                ExceptionCollector.appendException(
+                    UnknownFieldError(what='Template ' + (self.import_def),
+                                      field=name))
+
+    def _validate_type_version(self, version):
+        if version not in self.VALID_TEMPLATE_VERSIONS:
+            ExceptionCollector.appendException(
+                InvalidTemplateVersion(
+                    what=version + ' in ' + self.import_def,
+                    valid_versions=', '. join(self.VALID_TEMPLATE_VERSIONS)))