Accessing HAProxy statistics with Python
HAProxy exposes some if its statistics through a UNIX socket and it turns out it’s very easy to access it from Python, like below.
I guess the code is pretty self-explanatory – essentially it’s expecting you to give it a path to the socket and then to feed it with commands. Some commands may need an extra argument, like ‘show sess’ does and if you’re particularly impatient – or maybe you’re under a very heavy load – you can also you use the ‘timeout’ parameter to specify how long you’re willing to wait for HAProxy to reply.
The responses are returned as-is and actually I wouldn’t mind it if someone took the code and added a nice OO look’n'feel to it so that it read like here ..
stats = HAProxyStats('/tmp/haproxy-stat.sock') sess = stats.sess('0x19e8fd0') print(sess.svname) |
.. that could make for a useful project but for now, here’s some code that works today 
# -*- coding: utf-8 -*- from __future__ import absolute_import, division, print_function, unicode_literals # stdlib import logging import socket from cStringIO import StringIO from time import time from traceback import format_exc logger = logging.getLogger(__name__) class HAProxyStats(object): """ Used for communicating with HAProxy through its local UNIX socket interface. """ def __init__(self, socket_name=None): self.socket_name = socket_name def execute(self, command, extra="", timeout=200): """ Executes a HAProxy command by sending a message to a HAProxy's local UNIX socket and waiting up to 'timeout' milliseconds for the response. """ if extra: command = command + ' ' + extra buff = StringIO() end = time() + timeout client = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) try: client.connect(self.socket_name) client.send(command + '\n') while time() |
