Return hashes and expiration when fetching signed tags

util/tufmetadata/api.py

@@ -36,40 +36,43 @@ class TUFMetadataAPI(object):
     self._config = config
     self._client = client or config['HTTPCLIENT']
 
-  def get_default_tags(self, namespace, repository):
-    """ Gets the tag -> sha mappings in the 'targets/releases' delegation 
+  def get_default_tags_with_expiration(self, namespace, repository, targets_file=None):
+    """ Gets the tag -> sha mappings in the 'targets/releases' delegation
+        Returns tags, their hashes, and their 
     """
+    if not targets_file:
+      targets_file = 'targets/releases.json'
     gun = "%s/%s" % (namespace, repository)
+    
     try:
-      response = self._get(gun, "targets/releases.json")
-      json_response = response.json()
-      targets = self._parse_targets(json_response)
+      response = self._get(gun, targets_file)
+      signed = self._parse_signed(response.json())
+      targets = signed.get('targets')
+      expiration = signed.get('expires')
     except requests.exceptions.Timeout:
       logger.exception('Timeout when trying to get metadata for %s', gun)
-      return None, True
+      return None, None 
     except requests.exceptions.ConnectionError:
       logger.exception('Connection error when trying to get metadata for %s', gun)
-      return None, True
+      return None, None 
     except (requests.exceptions.RequestException, ValueError):
       logger.exception('Failed to get metadata for %s', gun)
-      return None, False
+      return None, None 
     except Non200ResponseException as ex:
-      return None, ex.response.status_code != 404 and ex.response.status_code != 400
+      logger.exception('Failed request for %s: %s', gun, str(ex))
+      return None, None 
     except InvalidMetadataException as ex:
       logger.exception('Failed to parse targets from metadata', str(ex))
-      return None, False 
+      return None, None 
     
-    return targets, False
+    return targets, expiration
   
-  def _parse_targets(self, json_response):
+  def _parse_signed(self, json_response):
     """ Attempts to parse the targets from a metadata response """
     signed = json_response.get('signed')
     if not signed:
       raise InvalidMetadataException("Could not find `signed` in metadata: %s" % json_response)
-    targets = signed.get('targets')
-    if not targets:
-      raise InvalidMetadataException("Could not find `targets` in metadata: %s" % json_response)
-    return targets
+    return signed 
   
   def _auth_header(self, gun):
     """ Generate a registry auth token for apostille"""