create class for security config validation

util/secscan/api.py

@@ -98,6 +98,54 @@ def get_priority_for_index(index):
 
  return 'Unknown'
 
+class SecurityConfigValidator(object):
+  def __init__(self, app, config_provider):
+    self._config_provider = config_provider
+
+    if not features.SECURITY_SCANNER:
+      return
+
+    self._security_config = app.config['SECURITY_SCANNER']
+    if self._security_config is None:
+      return
+
+    self._certificate = self._get_filepath('CA_CERTIFICATE_FILENAME') or False
+    self._public_key = self._get_filepath('PUBLIC_KEY_FILENAME')
+    self._private_key = self._get_filepath('PRIVATE_KEY_FILENAME')
+
+    if self._public_key and self._private_key:
+      self._keys = (self._public_key, self._private_key)
+    else:
+      self._keys = None
+
+  def _get_filepath(self, key):
+    config = self._security_config
+
+    if key in config:
+      with self._config_provider.get_volume_file(config[key]) as f:
+        return f.name
+
+    return None
+
+  def cert(self):
+    return self._certificate
+
+  def keypair(self):
+    return self._keys
+
+  def valid(self):
+    config = self._security_config
+
+    if (not features.SECURITY_SCANNER
+        or not config
+        or not 'ENDPOINT' in config
+        or not 'ENGINE_VERSION_TARGET' in config
+        or not 'DISTRIBUTED_STORAGE_PREFERENCE' in config
+        or (self._certificate is False and self._keys is None)):
+      return False
+
+    return True
+
 
 class SecurityScannerAPI(object):
   """ Helper class for talking to the Security Scan service (Clair). """
@@ -105,28 +153,12 @@ class SecurityScannerAPI(object):
     self.app = app
     self.config_provider = config_provider
 
-    if not features.SECURITY_SCANNER:
+    config_validator = SecurityConfigValidator(app, config_provider)
+    if not config_validator.valid():
       return
 
-    self.security_config = app.config['SECURITY_SCANNER']
-
-    self.certificate = self._getfilepath('CA_CERTIFICATE_FILENAME') or False
-    self.public_key = self._getfilepath('PUBLIC_KEY_FILENAME')
-    self.private_key = self._getfilepath('PRIVATE_KEY_FILENAME')
-
-    if self.public_key and self.private_key:
-      self.keys = (self.public_key, self.private_key)
-    else:
-      self.keys = None
-
-  def _getfilepath(self, config_key):
-    security_config = self.security_config
-
-    if config_key in security_config:
-      with self.config_provider.get_volume_file(security_config[config_key]) as f:
-        return f.name
-
-    return None
+    self.certificate = config_validator.cert()
+    self.keys = config_validator.keypair()
 
   def check_layer_vulnerable(self, layer_id, cve_id):
     """ Checks with Clair whether the given layer is vulnerable to the given CVE. """