#!/usr/bin/env python
"""
Date: 03/01/2017
Author: Long Chen
Description: A script to get MongoDB metrics
Requires: MongoClient in python
"""
from calendar import timegm
from time import gmtime
from pymongo import MongoClient, errors
from sys import exit
import json
class MongoDB(object):
"""main script class"""
# pylint: disable=too-many-instance-attributes
def __init__(self):
self.mongo_host = "127.0.0.1"
self.mongo_port = 27017
self.mongo_db = ["admin", ]
self.mongo_user = None
self.mongo_password = None
self.__conn = None
self.__dbnames = None
self.__metrics = []
def connect(self):
"""Connect to MongoDB"""
if self.__conn is None:
if self.mongo_user is None:
try:
self.__conn = MongoClient('mongodb://%s:%s' %
(self.mongo_host,
self.mongo_port))
except errors.PyMongoError as py_mongo_error:
print('Error in MongoDB connection: %s' %
str(py_mongo_error))
else:
try:
self.__conn = MongoClient('mongodb://%s:%s@%s:%s' %
(self.mongo_user,
self.mongo_password,
self.mongo_host,
self.mongo_port))
except errors.PyMongoError as py_mongo_error:
print('Error in MongoDB connection: %s' %
str(py_mongo_error))
def add_metrics(self, k, v):
"""add each metric to the metrics list"""
dict_metrics = {}
dict_metrics['key'] = k
dict_metrics['value'] = v
self.__metrics.append(dict_metrics)
def print_metrics(self):
"""print out all metrics"""
metrics = self.__metrics
for metric in metrics:
zabbix_item_key = str(metric['key'])
zabbix_item_value = str(metric['value'])
print('- ' + zabbix_item_key + ' ' + zabbix_item_value)
def get_db_names(self):
"""get a list of DB names"""
if self.__conn is None:
self.connect()
db_handler = self.__conn[self.mongo_db[0]]
master = db_handler.command('isMaster')['ismaster']
dict_metrics = {}
dict_metrics['key'] = 'mongodb.ismaster'
if master:
dict_metrics['value'] = 1
db_names = self.__conn.database_names()
self.__dbnames = db_names
else:
dict_metrics['value'] = 0
self.__metrics.append(dict_metrics)
def get_mongo_db_lld(self):
"""print DB list in json format, to be used for
mongo db discovery in zabbix"""
if self.__dbnames is None:
db_names = self.get_db_names()
else:
db_names = self.__dbnames
dict_metrics = {}
db_list = []
dict_metrics['key'] = 'mongodb.discovery'
dict_metrics['value'] = {"data": db_list}
if db_names is not None:
for db_name in db_names:
dict_lld_metric = {}
dict_lld_metric['{#MONGODBNAME}'] = db_name
db_list.append(dict_lld_metric)
dict_metrics['value'] = '{"data": ' + json.dumps(db_list) + '}'
self.__metrics.insert(0, dict_metrics)
def get_oplog(self):
"""get replica set oplog information"""
if self.__conn is None:
self.connect()
db_handler = self.__conn['local']
coll = db_handler.oplog.rs
op_first = (coll.find().sort('$natural', 1).limit(1))
op_last = (coll.find().sort('$natural', -1).limit(1))
# if host is not a member of replica set, without this check we will
# raise StopIteration as guided in
# http://api.mongodb.com/python/current/api/pymongo/cursor.html
if op_first.count() > 0 and op_last.count() > 0:
op_fst = (op_first.next())['ts'].time
op_last_st = op_last[0]['ts']
op_lst = (op_last.next())['ts'].time
status = round(float(op_lst - op_fst), 1)
self.add_metrics('mongodb.oplog', status)
current_time = timegm(gmtime())
oplog = int(((str(op_last_st).split('('))[1].split(','))[0])
self.add_metrics('mongodb.oplog-sync', (current_time - oplog))
def get_maintenance(self):
"""get replica set maintenance info"""
if self.__conn is None:
self.connect()
db_handler = self.__conn
fsync_locked = int(db_handler.is_locked)
self.add_metrics('mongodb.fsync-locked', fsync_locked)
try:
config = db_handler.admin.command("replSetGetConfig", 1)
connstring = (self.mongo_host + ':' + str(self.mongo_port))
connstrings = list()
for i in range(0, len(config['config']['members'])):
host = config['config']['members'][i]['host']
connstrings.append(host)
if connstring in host:
priority = config['config']['members'][i]['priority']
hidden = int(config['config']['members'][i]['hidden'])
self.add_metrics('mongodb.priority', priority)
self.add_metrics('mongodb.hidden', hidden)
except errors.PyMongoError:
print ('Error while fetching replica set configuration.'
'Not a member of replica set?')
except UnboundLocalError:
print ('Cannot use this mongo host: must be one of ' + ','.join(connstrings))
exit(1)
def get_server_status_metrics(self):
"""get server status"""
if self.__conn is None:
self.connect()
db_handler = self.__conn[self.mongo_db[0]]
ss = db_handler.command('serverStatus')
# db info
self.add_metrics('mongodb.version', ss['version'])
self.add_metrics('mongodb.storageEngine', ss['storageEngine']['name'])
self.add_metrics('mongodb.uptime', int(ss['uptime']))
self.add_metrics('mongodb.okstatus', int(ss['ok']))
# asserts
for k, v in ss['asserts'].items():
self.add_metrics('mongodb.asserts.' + k, v)
# operations
for k, v in ss['opcounters'].items():
self.add_metrics('mongodb.operation.' + k, v)
# memory
for k in ['resident', 'virtual', 'mapped', 'mappedWithJournal']:
self.add_metrics('mongodb.memory.' + k, ss['mem'][k])
# connections
for k, v in ss['connections'].items():
self.add_metrics('mongodb.connection.' + k, v)
# network
for k, v in ss['network'].items():
self.add_metrics('mongodb.network.' + k, v)
# extra info
self.add_metrics('mongodb.page.faults',
ss['extra_info']['page_faults'])
#wired tiger
if ss['storageEngine']['name'] == 'wiredTiger':
self.add_metrics('mongodb.used-cache',
ss['wiredTiger']['cache']
["bytes currently in the cache"])
self.add_metrics('mongodb.total-cache',
ss['wiredTiger']['cache']
["maximum bytes configured"])
self.add_metrics('mongodb.dirty-cache',
ss['wiredTiger']['cache']
["tracked dirty bytes in the cache"])
# global lock
lock_total_time = ss['globalLock']['totalTime']
self.add_metrics('mongodb.globalLock.totalTime', lock_total_time)
for k, v in ss['globalLock']['currentQueue'].items():
self.add_metrics('mongodb.globalLock.currentQueue.' + k, v)
for k, v in ss['globalLock']['activeClients'].items():
self.add_metrics('mongodb.globalLock.activeClients.' + k, v)
def get_db_stats_metrics(self):
"""get DB stats for each DB"""
if self.__conn is None:
self.connect()
if self.__dbnames is None:
self.get_db_names()
if self.__dbnames is not None:
for mongo_db in self.__dbnames:
db_handler = self.__conn[mongo_db]
dbs = db_handler.command('dbstats')
for k, v in dbs.items():
if k in ['storageSize', 'ok', 'avgObjSize', 'indexes',
'objects', 'collections', 'fileSize',
'numExtents', 'dataSize', 'indexSize',
'nsSizeMB']:
self.add_metrics('mongodb.stats.' + k +
'[' + mongo_db + ']', int(v))
def close(self):
"""close connection to mongo"""
if self.__conn is not None:
self.__conn.close()
if __name__ == '__main__':
mongodb = MongoDB()
mongodb.get_db_names()
mongodb.get_mongo_db_lld()
mongodb.get_oplog()
mongodb.get_maintenance()
mongodb.get_server_status_metrics()
mongodb.get_db_stats_metrics()
mongodb.print_metrics()
mongodb.close()
