Add config validation on startup (#2903)

* WIP

* Finish schema

Add three sections: security scanning, bittorrent support and feature flags.

util/config/provider/baseprovider.py

@@ -1,6 +1,11 @@
 import logging
 import yaml
 
+
+from jsonschema import validate, ValidationError
+
+
+from util.config.schema import CONFIG_SCHEMA
 from util.license import LICENSE_FILENAME, LicenseDecodeError, decode_license
 
 
@@ -31,6 +36,15 @@ def import_yaml(config_obj, config_file):
       if key.isupper():
         config_obj[key] = c[key]
 
+  if config_obj.get('SETUP_COMPLETE', True):
+    try:
+      validate(config_obj, CONFIG_SCHEMA)
+    except ValidationError:
+      # TODO: Change this into a real error
+      logger.exception('Could not validate config schema')
+  else:
+    logger.debug('Skipping config schema validation because setup is not complete')
+
   return config_obj
 
 
@@ -109,7 +123,7 @@ class BaseProvider(object):
         indicating that this container requires a restart.
     """
     raise NotImplementedError
-  
+
   def get_volume_path(self, directory, filename):
     """ Helper for constructing file paths, which may differ between providers. For example,
     kubernetes can't have subfolders in configmaps """