#!/usr/bin/python

import commands
import os
import re
import socket
import struct
import DNS
import time
from history import *


def get_success_ratio(measured):
    return float(len(filter(lambda x: x > 0, measured)))/float(len(measured))

def timed(method):

    def timeit(*args, **kw):
        ts = time.time()
        result = method(*args, **kw)
        te = time.time()

        #print '%r (%r, %r) %2.2f sec' % \
        #      (method.__name__, args, kw, te-ts)
        return (result, te-ts)

    return timeit

@timed
def check_dns(ip, protocol='udp'):
    try:
        #ip = ip[:-1] + "0"
        ro = DNS.Request(name="www.yahoo.com", qtype="A", server=ip, timeout=45)
        r = ro.req(protocol=protocol)
        r = "OK"
    except DNS.Base.DNSError, e:
        r = "Error: %s" % e
    return r
        
def get_nameserver_ips(filename):
    ip_re = re.compile("\d+\.\d+\.\d+\.\d+")
    ret = {}
    if not os.path.exists(filename):
        return ret

    f = open(filename, 'r')

    if 'resolv' in filename:
        for l in f:
            for field in l.strip().split():
                if ip_re.match(field) and field not in ret:
                    ret[field] = 0

    if 'ifcfg' in filename:
        for l in f:
            if 'DNS' not in l:
                continue
            for field in l.strip().split('='):
                field = field.replace('"', '')
                field = field.replace("'", '')
                if ip_re.match(field) and field not in ret:
                    ret[field] = 0
    return ret

def main():

    root_ips  = get_nameserver_ips('/etc/resolv.conf')
    slice_ips = get_nameserver_ips( '/vservers/princeton_comon/etc/resolv.conf')

    context_list = ['root', 'slice']
    proto_list = ['udp', 'tcp']

    sequence_list  = zip(sorted(context_list*2), zip(root_ips.keys(),sorted(proto_list*2)[::-1]))
    sequence_list += zip(sorted(context_list*2), zip(slice_ips.keys(),sorted(proto_list*2)[::-1]))

    if set(root_ips.keys()) == set(slice_ips.keys()):
        print "CONF-ROOT_SLICE-MATCH",
    else:
        print "CONF-ROOT_SLICE-MISMATCH",

    for i,(context,(ip,proto)) in enumerate(sequence_list):
        (s,t) = check_dns(ip, proto)
        if "Error" in s: t = -1
        dns = HistoryFile("dns_history_%s_%s%s.dat" % (context, proto, i), DNSHistory)
        dns.append(t)
        print get_success_ratio(dns.get()),
        dns.close()
    
    c_dns = os.popen("curl -s http://localhost:3121 | grep -a DNSFail").read().strip()
    if len(c_dns) > 9 and "DNS" in c_dns:
        c_dns = "cm " + c_dns[9:]
    else:
        c_dns = ""
    print c_dns,

    print ""


if __name__ == "__main__":
    main()