Supervisord memory check plugin for serverdensity.io

SupervisordMemory.py

#!/usr/bin/env python

"""
Server Density Supervisord plugin.
Track the number of processes in each state.

For possible states see the docs at 
http://supervisord.org/subprocess.html#process-states
"""

import os
import httplib
import urllib
import xmlrpclib


from supervisor import childutils
from supervisor.datatypes import byte_size

def usage():
	print doc
	sys.exit(255)

def shell(cmd):
	return os.popen(cmd).read()

SUPERVISORD_RPC_URL = "http://localhost:9001/RPC2"


class SupervisordMemory(object):
	"""Collect and return details of a local Supervisord instance.
	"""
	def __init__(self, agent_config, checks_logger, raw_config):
		self.agent_config = agent_config
		self.checks_logger = checks_logger
		self.raw_config = raw_config
		self.pscommand = 'ps -orss= -p %s'
	
	def run(self):
		stats = {}
		
		try:
			# # Pull the supervisord rpc URL from the config or default
			url = self.raw_config['Main'].get('supervisord_rpc_url',
					SUPERVISORD_RPC_URL)
			server = xmlrpclib.Server(url)
		except KeyError:
			# Should only happen if Main section of config is missing
			self.checks_logger.error('Missing sd-agent configuration')
			server = xmlrpclib.Server(SUPERVISORD_RPC_URL)
			
		try:
			server_info = server.supervisor.getAllProcessInfo()
			self.checks_logger.debug(server_info)
			stats.update(self.get_process_counts(server_info))
		except (xmlrpclib.Fault, httplib.HTTPException), exc:
			stats = {}
			self.checks_logger.debug(str(exc))
		except Exception as e:
                	template = "An exception of type {0} occured. Arguments:\n{1!r}"
			message = template.format(type(e).__name__, e.args)
			self.checks_logger.error(message)
		return stats
	
	def get_process_counts(self, server_info):
		processes = {}
		processes['total'] = 0
		for info in server_info:
			pid = info['pid']
			name = info['name']
			group = info['group']
			pname = '%s:%s' % (group, name)
			processes[pname] = 0
			if group not in processes:
				processes[group] = 0
			if not pid:
				# ps throws an error in this case (for processes
				# in standby mode, non-auto-started).
				continue

			data = shell(self.pscommand % pid)
			if not data:
				# no such pid (deal with race conditions)
				continue

			try:
				rss = data.lstrip().rstrip()
				rss = int(rss) * 1024 # rss is in KB
				processes[pname] = rss
				processes[group] += rss
				processes['total'] += rss
			except ValueError:
				# line doesn't contain any data, or rss cant be intified
				continue
		
		return processes