mongodb-gmetric.py

#! /usr/bin/python

from subprocess import Popen
import sys, os, urllib2

try:
    import json
except ImportError:
    import simplejson as json
   
GMETRIC = "/usr/bin/gmetric --name=\"%s\" --value=\"%s\" --type=\"int32\" --units=\"%s\""

class ServerStatus:
    ops_tmp_file = os.path.join("/", "tmp", "mongo-prevops")    

    def __init__(self, port=None):
        if (port == None):
            port = 28017
        
        self.port = port
        self.status = self.getServerStatus()
        # call individual metrics
        for f in ["conns", "btree", "repl", "ops", "lock", "mem"]:
            getattr(self,f)()

    def getServerStatus(self):
        raw = urllib2.urlopen( "http://127.0.0.1:%s/_status" % self.port ).read()
        return json.loads( raw )["serverStatus"]
    
    def callGmetric(self, d):
        for k,v in d.iteritems():
            cmd = GMETRIC % ("mongodb_%s_%s" % (k, self.port), v[0], v[1])
            Popen(cmd, shell=True)
    
    def conns(self):
        ss = self.status
        self.callGmetric({
            "connections" : (ss["connections"]["current"], "connections")
        })

    def btree(self):
        try:
            b = self.status["indexCounters"]["btree"]
            self.callGmetric({
                "btree_accesses" : (b["accesses"], "count"),
                "btree_hits" : (b["hits"], "count"),
                "btree_misses" : (b["misses"], "count"),
                "btree_resets" : (b["resets"], "count"),
                "btree_miss_ratio" : (b["missRatio"], "ratio"),
            })
        except:
            pass
    
    def mem(self):
        try:
            m = self.status["mem"]
            self.callGmetric({
                "mem_resident" : (m["resident"], "MB"),
                "mem_virtual" : (m["virtual"], "MB"),
                "mem_mapped" : (m["mapped"], "MB"),
            })
        except:
            pass
       

    def ops(self):
        out = {}
        cur_ops = self.status["opcounters"]
        try:
            f = open(self.ops_tmp_file, "r")
            content = f.read()
            prev_ops = json.loads(content)
            f.close()
        except (ValueError, IOError):
            prev_ops = {}
        
        for k,v in cur_ops.iteritems():
            if k in prev_ops:
                name = k + "s_per_second"
                if k == "query":
                    name = "queries_per_second"
                out[name] = ((float(v) - float(prev_ops[k]) ) / 60, "ops/s")

        f = open(self.ops_tmp_file, 'w') 
        try:
            f.write(json.dumps(cur_ops))
        finally:
            f.close()

        self.callGmetric(out)
    
    def repl(self):
        try:
            self.callGmetric({
                "is_master" : (self.status["repl"]["ismaster"], "boolean")
            })
        except:
            pass

    def lock(self):
        try:
            self.callGmetric({
                "lock_ratio" : (self.status["globalLock"]["ratio"], "ratio")
            })
        except:
            pass
    
if __name__ == "__main__":
    port = None

    if (len(sys.argv) == 2):  
        port = sys.argv[1]

    ServerStatus(port)