Add 'get_health' to Command class

Provide a convenience function that summarizes the overall health
of the managed system based.  Currently, it just enumerates all
SDR indicated sensors seeking unhealthy readings.

Change-Id: Ifce6d05623acc86b6bf42ceb57824b65eefa36ae

ipmictl.py

@@ -60,6 +60,8 @@ def docommand(result, ipmisession):
     elif cmmand == 'sensors':
         for reading in ipmisession.get_sensor_data():
             print repr(reading)
+    elif cmmand == 'health':
+        print repr(ipmisession.get_health())
     elif cmmand == 'raw':
         print ipmisession.raw_command(netfn=int(args[0]),
                                       command=int(args[1]),

pyghmi/ipmi/command.py

@@ -15,6 +15,7 @@
 # limitations under the License.
 # This represents the low layer message framing portion of IPMI
 
+import pyghmi.constants as const
 import pyghmi.exceptions as exc
 
 from pyghmi.ipmi.private import session
@@ -291,6 +292,22 @@ class Command(object):
         self.powerstate = 'on' if (response['data'][0] & 1) else 'off'
         return {'powerstate': self.powerstate}
 
+    def get_health(self):
+        """Summarize health of managed system
+
+        This provides a summary of the health of the managed system.
+        It additionally provides an iterable list of reasons for
+        warning, critical, or failed assessments.
+        """
+        summary = {}
+        summary['badreadings'] = []
+        summary['health'] = const.Health.Ok
+        for reading in self.get_sensor_data():
+            if reading.health != const.Health.Ok:
+                summary['health'] |= reading.health
+                summary['badreadings'].append(reading)
+        return summary
+
     def get_sensor_data(self):
         """Get sensor reading objects