"""
.. module:: postgresql
:platform: Unix
:synopsis: A source module for postgres stats
.. moduleauthor:: Colin Alston <colin@imcol.in>
"""
import time
import exceptions
from twisted.internet import defer
from twisted.enterprise import adbapi
from twisted.python import log
from zope.interface import implementer
from tensor.interfaces import ITensorSource
from tensor.objects import Source
from tensor.aggregators import Counter64
@implementer(ITensorSource)
[docs]class PostgreSQL(Source):
"""Reads PostgreSQL metrics
**Configuration arguments:**
:param host: Database host
:type host: str.
:param port: Database port
:type port: int.
:param user: Username
:type user: str.
:param password: Password
:type password: str.
**Metrics:**
:(service name).(database name).(metrics): Metrics from pg_stat_database
"""
def __init__(self, *a, **kw):
Source.__init__(self, *a, **kw)
self.user = self.config.get('user', 'postgres')
self.password = self.config.get('password', '')
self.port = self.config.get('port', 5432)
self.host = self.config.get('host', '127.0.0.1')
@defer.inlineCallbacks
def get(self):
try:
p = adbapi.ConnectionPool('psycopg2',
database='postgres',
host=self.host,
port=self.port,
user=self.user,
password=self.password)
cols = (
('xact_commit', 'commits'),
('xact_rollback', 'rollbacks'),
('blks_read', 'disk.read'),
('blks_hit', 'disk.cache'),
('tup_returned', 'returned'),
('tup_fetched', 'selects'),
('tup_inserted', 'inserts'),
('tup_updated', 'updates'),
('tup_deleted', 'deletes'),
('deadlocks', 'deadlocks')
)
keys, names = zip(*cols)
q = yield p.runQuery(
'SELECT datname,numbackends,%s FROM pg_stat_database' % (
','.join(keys))
)
for row in q:
db = row[0]
threads = row[1]
if db not in ('template0', 'template1'):
self.queueBack(self.createEvent('ok',
'threads: %s' % threads,
threads,
prefix='%s.threads' % db)
)
for i, col in enumerate(row[2:]):
self.queueBack(self.createEvent('ok',
'%s: %s' % (names[i], col),
col,
prefix='%s.%s' % (db, names[i]),
aggregation=Counter64)
)
yield p.close()
defer.returnValue(self.createEvent('ok', 'Connection ok', 1,
prefix='state'))
except exceptions.ImportError:
log.msg('tensor.sources.database.postgresql.PostgreSQL'
' requires psycopg2')
defer.returnValue(None)
except Exception as e:
defer.returnValue(self.createEvent('critical',
'Connection error: %s' % str(e).replace('\n',' '),
0, prefix='state')
)