VES: add new tag to strip extra dashes

The `!StripExtraDash` tag can be used in YAML configuration
file to strip extra dashes in the YAML filed value. This may
happen if some of the collectd plugin field (plugin_instance,
type_instace etc.) is set to empty value but the field is
specified in the YAML configuration file. For instance:

"{vl.plugin_instance}-{vl.type_instance}"

The result fo the example above can be string consisting
extra dashes if `type_instace` field is not set by a collectd
plugin:

"load-"

Change-Id: I5cf7b19902acdfb0b4a93f3bf0c8b8e05cff2e97
Signed-off-by: Mytnyk, Volodymyr <volodymyrx.mytnyk@intel.com>

1 files changed, 10 insertions, 1 deletions

diff --git a/3rd_party/collectd-ves-app/ves_app/normalizer.py b/3rd_party/collectd-ves-app/ves_app/normalizer.py
index ddaad617..84de5e33 100644
--- a/3rd_party/collectd-ves-app/ves_app/normalizer.py
+++ b/3rd_party/collectd-ves-app/ves_app/normalizer.py
@@ -288,7 +288,7 @@ class Item(yaml.YAMLObject):
     def format_node(cls, mapping, metric):
         if mapping.tag in [
                 'tag:yaml.org,2002:str', Bytes2Kibibytes.yaml_tag,
-                Number.yaml_tag]:
+                Number.yaml_tag, StripExtraDash.yaml_tag]:
             return yaml.ScalarNode(mapping.tag, mapping.value.format(**metric))
         elif mapping.tag == 'tag:yaml.org,2002:map':
             values = []
@@ -459,6 +459,15 @@ class Number(yaml.YAMLObject):
             return float(node.value)
 
 
+class StripExtraDash(yaml.YAMLObject):
+    """Class to process StripExtraDash tag"""
+    yaml_tag = u'!StripExtraDash'
+
+    @classmethod
+    def from_yaml(cls, loader, node):
+        return '-'.join([ x for x in node.value.split('-') if len(x) > 0])
+
+
 class MapValue(yaml.YAMLObject):
     """Class to process MapValue tag"""
     yaml_tag = u'!MapValue'