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+# groups.json
+
+This file contains an array of group definitions.  In this usage, a group
+refers to a group of D-Bus objects that all of the same D-Bus path and
+interface, and are acted upon by actions and triggers in events.json.
+Only the D-Bus objects paths are specified in this file, the interface and
+properties are specified at the time of usage in events.json.
+
+## JSON example
+
+```
+[
+  {
+     "name": "occ objects",
+     "service": "org.open_power.OCC.Control",
+     "members": [
+       "/org/open_power/control/occ0",
+       "/org/open_power/control/occ1"
+     ]
+   }
+]
+```
+
+## Attributes
+
+### members
+An array of the D-Bus object paths that are in the group.  Required.
+
+### name
+The group name.  This is how the group is referenced in events.json.
+Required.
+
+### service
+If known, the D-Bus service name that provides these D-bus objects.  All
+members of the group must be hosted by the same service for this to be used.
+This provides performance improvements in certain cases.  Optional.