source: trunk/daemon/togad.py @ 8

#!/usr/bin/env python

from xml.sax import make_parser
from xml.sax.handler import ContentHandler 
import socket
import sys

# Specify debugging level here;
#
# >10 = metric XML
# >9  = host,cluster,grid,ganglia XML
#
DEBUG_LEVEL = 9

"""
This is TOrque-GAnglia's data Daemon
"""

class GangliaXMLHandler( ContentHandler ):
        "Parse Ganglia's XML"

        metrics = [ ]

        def startElement( self, name, attrs ):
                "Store appropriate data from xml start tags"

                if name == 'GANGLIA_XML':
                        self.XMLSource = attrs.get('SOURCE',"")
                        self.gangliaVersion = attrs.get('VERSION',"")
                        if (DEBUG_LEVEL>9): print 'Found XML data: source %s version %s' %( self.XMLSource, self.gangliaVersion )

                elif name == 'GRID':
                        self.gridName = attrs.get('NAME',"")
                        if (DEBUG_LEVEL>9): print '`-Grid found: %s' %( self.gridName )

                elif name == 'CLUSTER':
                        self.clusterName = attrs.get('NAME',"")
                        if (DEBUG_LEVEL>9): print ' |-Cluster found: %s' %( self.clusterName )

                elif name == 'HOST':     
                        self.hostName = attrs.get('NAME',"")
                        self.hostIp = attrs.get('IP',"")
                        self.hostReported = attrs.get('REPORTED',"")
                        if (DEBUG_LEVEL>9): print ' | |-Host found: %s - ip %s reported %s' %( self.hostName, self.hostIp, self.hostReported )

                elif name == 'METRIC':
                        myMetric = { }
                        myMetric['name'] = attrs.get('NAME',"")
                        myMetric['val'] = attrs.get('VAL',"")

                        self.metrics.append( myMetric ) 
                        if (DEBUG_LEVEL>10): print ' | | |-metric: %s:%s' %( myMetric['name'], myMetric['val'] )

                return

        #def endElement( self, name ):
                #if name == 'ganglia_xml':

                #if name == 'grid':

                #if name == 'cluster':

                #if name == 'host':     

                #if name == 'metric':

class GangliaXMLGatherer:
        "Setup a connection and file object to Ganglia's XML"

        s = None

        def __init__( self, host, port ):
                "Store host and port for connection"

                self.host = host
                self.port = port

        def __del__( self ):
                "Kill the socket before we leave"

                self.s.close()

        def getFileObject( self ):
                "Connect, and return a file object"

                for res in socket.getaddrinfo( self.host, self.port, socket.AF_UNSPEC, socket.SOCK_STREAM ):
                        af, socktype, proto, canonname, sa = res
                        try:
                                self.s = socket.socket( af, socktype, proto )
                        except socket.error, msg:
                                self.s = None
                                continue
                        try:
                                self.s.connect( sa )
                        except socket.error, msg:
                                self.s.close()
                                self.s = None
                                continue
                        break

                if self.s is None:
                        print 'Could not open socket'
                        sys.exit(1)

                return self.s.makefile( 'r' )

class GangliaXMLProcessor:

        def daemon(self):
                "Run as daemon forever"

                self.DAEMON = 1

                # Fork the first child
                #
                pid = os.fork()
                if pid > 0:
                        sys.exit(0)  # end parrent

                # creates a session and sets the process group ID 
                #
                os.setsid()

                # Fork the second child
                #
                pid = os.fork()
                if pid > 0:
                        sys.exit(0)  # end parrent

                # Go to the root directory and set the umask
                #
                os.chdir('/')
                os.umask(0)

                sys.stdin.close()
                sys.stdout.close()
                sys.stderr.close()

                os.open('/dev/null', 0)
                os.dup(0)
                os.dup(0)

                self.run()

        def run(self):
                "Main thread"

                while ( 1 ):
                        self.processXML()
                        time.sleep( 5 )

        def processXML( self ):
                "Process XML"

                myXMLGatherer = GangliaXMLGatherer( 'localhost', 8651 ) 

                myParser = make_parser()   
                myHandler = GangliaXMLHandler()
                myParser.setContentHandler( myHandler )

                myParser.parse( myXMLGatherer.getFileObject() )

def main():
        "Program startup"

        myProcessor = GangliaXMLProcessor()
        myProcessor.processXML()

# Let's go
main()