statsd client

statsd.py

import sys
import random
import logging
from socket import socket, AF_INET, SOCK_DGRAM

from django.conf import settings

logger = logging.getLogger(__name__)

class Statsd(object):
    """
    Send statstics to the stats daemon over UDP. 
    
    Expects a STATSD setting in django.conf.settings
    STATSD = {
        'HOST': '127.0.0.1',
        'PORT': 8125,
    }

    Additional parameters in STATSD:
    `PREFIX`, Prefix each stat key with value.
    """

    @staticmethod
    def timing(stat, time, sample_rate=1):
        """
        Log timing information
        >>> from statsd import Statsd
        >>> Statsd.timing('some.time', 500)
        """
        stats = {}
        stats[stat] = "%d|ms" % time
        Statsd.send(stats, sample_rate)

    @staticmethod
    def increment(stats, sample_rate=1):
        """
        Increments one or more stats counters
        >>> Statsd.increment('some.int')
        >>> Statsd.increment('some.int',0.5)
        """
        Statsd.update_stats(stats, 1, sample_rate)

    @staticmethod
    def decrement(stats, sample_rate=1):
        """
        Decrements one or more stats counters
        >>> Statsd.decrement('some.int')
        """
        Statsd.update_stats(stats, -1, sample_rate)

    @staticmethod
    def update_stats(stats, delta=1, sampleRate=1):
        """
        Updates one or more stats counters by arbitrary amounts
        >>> Statsd.update_stats('some.int',10)
        """
        if (type(stats) is not list):
            stats = [stats]
        data = {}
        for stat in stats:
            data[stat] = "%s|c" % delta

        Statsd.send(data, sampleRate)

    @staticmethod
    def send(data, sample_rate=1):
        """
        Squirt the metrics over UDP
        """
        if not settings.STATSD or len(set(settings.STATSD.keys()).intersection(['HOST', 'PORT'])) < 2:
            logger.warning("You must set a HOST and PORT key in the STATSD \
                    dictionary within the project settings.")
            return

        prefix = settings.STATSD.get('PREFIX', '')

        # Adjust the keys within the data
        addr = (settings.STATSD['HOST'], settings.STATSD['PORT'])

        sampled_data = {}

        if(sample_rate < 1):
            if random.random() <= sample_rate:
                for stat in data.keys():
                    value = data[stat]
                    sampled_data[stat] = "%s|@%s" %(value, sample_rate)
        else:
            sampled_data=data

        udp_sock = socket(AF_INET, SOCK_DGRAM)
        try:
            for stat in sampled_data.keys():
                value = sampled_data[stat]

                if prefix:
                    stat = '.'.join([prefix, stat])
                send_data = "%s:%s" % (stat, value)
                logger.debug("Statsd - %s" % send_data)
                udp_sock.sendto(send_data, addr)
        except:
            # If anythin happens, log it.
            logger.error("Unexpected error sending to statsd", exc_info=sys.exc_info())