AMBARI-4917 when pushing a large config file (like log4j), don't show all content in log (dsen)

ambari-agent/src/main/python/resource_management/core/logger.py

@@ -58,11 +58,15 @@ class Logger:
     
   @staticmethod  
   def _get_resource_repr(resource):
+    MESSAGE_MAX_LEN = 256
     arguments_str = ""
     for x,y in resource.arguments.iteritems():
       
       # strip unicode 'u' sign
       if isinstance(y, unicode):
+        # don't show long messages
+        if len(y) > MESSAGE_MAX_LEN:
+          y = '...'
         val = repr(y).lstrip('u')
       # don't show dicts of configurations
       # usually too long