#!/usr/bin/python
# This check monitors the number of state changes in the given
# time interval and alerts if the given amount of changes occured.
# This is slightly different to the Nagios flap detection as it
# uses hard parameters.

import sys, getopt, time, os, socket

try:
    import livestatus
except ImportError:
    sys.stderr.write('The python livestatus api module is missing. Please install from\n'
                     'Check_MK livestatus sources to a python import path.\n')
    sys.exit(1)

def usage():
    sys.stderr.write("""check_flapping

USAGE: check_flapping [-r MINUTES] [-w NUM] [-c NUM] [-l PATH] HOST [PATTERNS...]
       check_flapping -h

ARGUMENTS:
  HOST                          Host name or IP address of the host to check
  PATTERNS                      One or several regex patterns to match service
                                descriptions to be monitored by this check

OPTIONS:
  -h, --help                    Show this help message and exit
  -l PATH                       Path to livestatus socket (Autodetected in OMD)
  -r MINUTES                    Timerange in the past to observe, given in minutes
  -w NUM                        Minumum number of state changes to raise a WARNING state
  -c NUM                        Minumum number of state changes to raise a CRITICALstate

""")

short_options = 'hr:w:c:l:'

try:
    opts, args = getopt.getopt(sys.argv[1:], short_options)
except getopt.GetoptError, err:
    sys.stderr.write("%s\n" % err)
    sys.exit(1)

hostname     = None
socket_path  = ''
svc_patterns = []
timerange    = 60
warn, crit   = 2, 3

for o,a in opts:
    if o == '-h':
        usage()
        sys.exit(0)
    elif o == '-r':
    	timerange = int(a)
    elif o == '-w':
        warn = int(a)
    elif o == '-c':
        crit = int(a)
    elif o == '-l':
        socket_path = a

if len(args) == 0:
    sys.stderr.write('ERROR: No host given.\n')
    sys.exit(1)
elif len(args) == 1:
    sys.stderr.write('ERROR: No service pattern given.\n')
    sys.exit(1)

hostname = args[0]
svc_patterns = args[1:]

if not socket_path and 'OMD_ROOT' in os.environ:
    socket_path = os.environ['OMD_ROOT'] + '/tmp/run/live'

if not os.path.exists(socket_path):
    sys.stderr.write('ERROR: Livestatus socket (%s) does not exist\n' % socket_path)
    sys.exit(1)

svc_filter = ''
for pattern in svc_patterns:
    svc_filter += 'Filter: service_description ~ %s\n' % pattern
if len(svc_patterns) > 1:
    svc_filter += 'Or: %d\n'  % len(svc_patterns)

query = (
    'GET log\n'
    'Columns: service_description current_service_scheduled_downtime_depth\n'
    'Filter: host_name = %s\n'
    '%s'
    'Filter: log_time >= %d\n'
    'Filter: class = 1\n'
    'Stats: state != 999\n'
) % (hostname, svc_filter, int(time.time() - (timerange * 60)))

c = livestatus.SingleSiteConnection('unix:' + socket_path)
response = c.query_table(query)

state  = 0
output = []
for svc_desc, downtime_depth, num in response:
    if int(downtime_depth) != 0:
        continue # skip services in downtime
    if num >= crit:
        output.append('%s: %d (!!)' % (svc_desc, num))
        state = 2
    elif num >= warn:
        output.append('%s: %d (!!)' % (svc_desc, num))
        state = max(state, 1)

if not output:
    output.append('Number of state changes not critical')

sys.stdout.write('%s - %s\n' % (['OK', 'WARN', 'CRIT'][state], ','.join(output)))
sys.exit(state)