add memory usage beacon

Beacon used for testing the percent of memory used

salt/beacons/memusage.py

@@ -0,0 +1,75 @@
+# -*- coding: utf-8 -*-
+'''
+Beacon to monitor memory usage.
+
+.. versionadded::
+
+:depends: python-psutil
+'''
+
+# Import Python libs
+from __future__ import absolute_import
+import logging
+import re
+
+# Import Salt libs
+import salt.utils
+
+# Import Third Party Libs
+try:
+    import psutil
+    HAS_PSUTIL = True
+except ImportError:
+    HAS_PSUTIL = False
+
+log = logging.getLogger(__name__)
+
+__virtualname__ = 'memusage'
+
+
+def __virtual__():
+    if salt.utils.is_windows():
+        return False
+    elif HAS_PSUTIL is False:
+        return False
+    else:
+        return __virtualname__
+
+
+def validate(config):
+    '''
+    Validate the beacon configuration
+    '''
+    # Configuration for diskusage beacon should be a list of dicts
+    if not isinstance(config, dict):
+        log.info('Configuration for diskusage beacon must be a dictionary.')
+        return False
+    return True
+
+
+
+def beacon(config):
+    '''
+    Monitor the memory usage of the minion
+
+    Specify thresholds for percent used and only emit a beacon if it is exceeded.
+
+    .. code-block:: yaml
+
+        beacons:
+          memusage:
+            - percent: 63%
+    '''
+    ret = []
+    for memusage in config:
+        mount = memusage.keys()[0]
+        _current_usage = psutil.virtual_memory()
+
+        current_usage = _current_usage.percent
+        monitor_usage = memusage[mount]
+        if '%' in monitor_usage:
+            monitor_usage = re.sub('%', '', monitor_usage)
+        monitor_usage = float(monitor_usage)
+        if current_usage >= monitor_usage:
+            ret.append({'memusage': current_usage})
+    return ret