Validate flavor specification in config

Validate that at least one of min-ram or flavor-name are present.

Change-Id: I2e42b0d6176e5a15e1ceb2a77b9d557bc0704d50

nodepool/cmd/config_validator.py

@@ -24,13 +24,21 @@ class ConfigValidator:
         self.config_file = config_file
 
     def validate(self):
-        pool_label = {
+        label_min_ram = v.Schema({v.Required('min-ram'): int}, extra=True)
+
+        label_flavor_name = v.Schema({v.Required('flavor-name'): str},
+                                     extra=True)
+
+        pool_label_main = {
             v.Required('name'): str,
             v.Required('diskimage'): str,
             'min-ram': int,
             'flavor-name': str,
         }
 
+        pool_label = v.All(pool_label_main,
+                           v.Any(label_min_ram, label_flavor_name))
+
         pool = {
             'name': str,
             'networks': [str],