quick ldap dsa healthcheck service

dsa-http-svc-chk

#!/usr/bin/env python3
"""simple socket service simulating an HTTP response to see if LDAP DSA is alive                                                                      
"""
from subprocess import Popen, PIPE
from json import dumps
import socket
import sys

bind_host = ""
bind_port = 1200
conn_queue = 10

def checkdsa():
    """checks if dsa is active

    Requires:
    * /usr/bin/ldapsearch

    Will pass along any raised errors.

    Returns:
    (result, detail)
    result(bool) - true if dsa is active, false otherwise
    detail(object)
    detail.alive(bool) - same as result
    detail.rc(int) - returncode of check
    detail.out(str) - lines of output
    detail.err(str) - lines of error
    """
    proc = Popen([
        "/usr/bin/ldapsearch",
        "-xZZH",
        "ldap://localhost",
        "-b",
        "cn=state"
    ], stdout=PIPE, stderr=PIPE)
    (out, err) = proc.communicate()
    rc = proc.wait()

    detail = {}
    detail['alive'] = False
    detail['rc'] = rc
    detail['out'] = out.decode("utf-8").split("\n")
    detail['err'] = err.decode("utf-8").split("\n")

    if rc == 0:
        for line in detail['out']:
            if line == "dsaIsActive: TRUE":
                detail['alive'] = True
                return (True, detail)
    return (False, detail)

def printhttp(code, data):
    print(printshttp(code,data))

def printshttp(code, data):
    """prints a fake http response

    Parameters:
    code(str) - a string including the http code and title (ie. "200 OK")
    data(object) - a payload to deliver to the browser via. JSON
    """
    response = dumps(data)
    return("""HTTP/1.0 %s
Content-Type: application/json; charset=UTF-8
Content-Length: %s

%s
"""%(code, len(response), response))

if __name__ == "__main__":
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    try:
        s.bind((bind_host,bind_port))
    except socket.err as msg:
        print("Bind failed, the service might already be running: %s"%msg)
        sys.exit(1)

    s.listen(conn_queue)
    while True:
        conn, addr = s.accept()
        (ok, detail) = checkdsa()
        if ok:
            conn.sendall(printshttp("200 OK", detail).encode())
        else:
            conn.sendall(printshttp("500 Internal Server Error", detail).encode())
        conn.close()

dsachk.service

[Unit]
Description=DSA Check Service

[Service]
Type=notify
ExecStart=/usr/local/bin/dsa-http-svc-chk
UMask=0066
Restart=on-failure

[Install]
WantedBy=multi-user.target