pip install haproxy-cli

$ haproxy-cli --help

usage: haproxy-cli [-h] [-v] [-c COMMAND] [-l] [-H] [-s SERVER] [-b BACKEND]
                  [-w WEIGHT] [-k SOCKET]

A tool to interact with HAProxy

optional arguments:
  -h, --help            show this help message and exit
  -v, --verbose         Be verbose.
  -c COMMAND, --command COMMAND
                        Type of command. Default info
  -l, --list-commands   Lists available commands.
  -H, --help-command    Shows help for the given command.
  -s SERVER, --server SERVER
                        Attempt action on given server.
  -b BACKEND, --backend BACKEND
                        Set backend to act upon.
  -w WEIGHT, --weight WEIGHT
                        Specify weight for a server.
  -k SOCKET, --socket SOCKET
                        Socket to talk to HAProxy. It accepts
                        unix:///path/to/socket or tcp://1.2.3.4[:port]
                        addresses. If there is no match
                        for protocol, then it assumes a UNIX socket file.

$ haproxy-cli -c frontends

$ haproxy-cli -c servers -b example_backend

$ haproxy-cli -c get-weight -b example_backend -s server1

$ haproxy-cli -c set-weight -b example_backend -s server1 -w 99

$ haproxy-cli -k /run/haproxy/admin.sock -c backends

#!/usr/bin/env python

from haproxy.conn import HaPConn
from haproxy import cmds

try:
    socket_conn = HaPConn('/var/run/haproxy.socket')

    if socket_conn:
        print(socket_conn.sendCmd(cmds.showInfo()))
    else:
        print('Could not open socket')

except Exception as exc:
    print(exc)