Support extracting the main template from a CSAR archive

Improve the CSAR support by adding an interface for returning the content
of the main template. Also, fix an issue in the CSAR package where reference
to the main template is missing.

Change-Id: I417fef12716445387e376b77582ac92f6dc06176
Partially-Implements: blueprint tosca-csar-translation

toscaparser/prereq/csar.py

@@ -100,13 +100,8 @@ class CSAR(object):
     def get_main_template(self):
         return self._get_metadata('Entry-Definitions')
 
-    def get_description(self):
-        desc = self._get_metadata('Description')
-        if desc is not None:
-            return desc
-
+    def get_main_template_yaml(self):
         main_template = self.get_main_template()
-        # extract the description from the main template
         data = self.zfile.read(main_template)
         invalid_tosca_yaml_err_msg = (
             _('The file %(template)s in %(csar)s does not contain valid TOSCA '
@@ -116,7 +111,15 @@ class CSAR(object):
             tosca_yaml = yaml.load(data)
             if type(tosca_yaml) is not dict:
                 raise ValidationError(message=invalid_tosca_yaml_err_msg)
-            self.metadata['Description'] = tosca_yaml['description']
+            return tosca_yaml
         except Exception:
             raise ValidationError(message=invalid_tosca_yaml_err_msg)
+
+    def get_description(self):
+        desc = self._get_metadata('Description')
+        if desc is not None:
+            return desc
+
+        self.metadata['Description'] = \
+            self.get_main_template_yaml()['description']
         return self.metadata['Description']

toscaparser/tests/data/CSAR/tosca_single_instance_wordpress/TOSCA-Metadata/TOSCA.meta

@@ -1,7 +1,5 @@
 TOSCA-Meta-File-Version: 1.0
 CSAR-Version: 1.1
 Created-By: OASIS TOSCA TC
-
-Name: Definitions/tosca_single_instance_wordpress.yaml
+Entry-Definitions: Definitions/tosca_single_instance_wordpress.yaml
 Content-Type: application/vnd.oasis.tosca.definitions.yaml
-

toscaparser/tests/test_prereq.py

@@ -15,6 +15,7 @@ import os
 from toscaparser.common.exception import ValidationError
 from toscaparser.prereq.csar import CSAR
 from toscaparser.tests.base import TestCase
+import toscaparser.utils
 from toscaparser.utils.gettextutils import _
 
 
@@ -109,3 +110,11 @@ class CSARPrereqTest(TestCase):
         self.assertEqual('tosca_helloworld.yaml', csar.get_main_template())
         self.assertEqual('Template for deploying a single server with '
                          'predefined properties.', csar.get_description())
+
+    def test_csar_main_template(self):
+        path = os.path.join(self.base_path, "data/CSAR/csar_hello_world.zip")
+        csar = CSAR(path)
+        yaml_file = os.path.join(os.path.dirname(os.path.abspath(__file__)),
+                                 "data/tosca_helloworld.yaml")
+        expected_yaml = toscaparser.utils.yamlparser.load_yaml(yaml_file)
+        self.assertEqual(expected_yaml, csar.get_main_template_yaml())