#!/usr/bin/python

import json
import urllib2
import sys
from jinja2 import Template

try:
    data = json.load(urllib2.urlopen('http://169.254.169.254/latest/user-data'))
    ip = urllib2.urlopen('http://169.254.169.254/latest/meta-data/local-ipv4').read()

except:
    print >> sys.stderr, 'Was not able to connect to the Amazon API'
    sys.exit(2)

zone_template="""
zone "{{user_data['domain']}}" IN {
  type forward;
  forward only;
  forwarders { {{ipaddr}}  port 8600; };
};
"""
zt = Template(zone_template)

main_config = open("/etc/bind/zones.consul", "w")
main_config.write(zt.render(user_data=data, ipaddr=ip))
main_config.close()

local_config = open("/etc/bind/named.conf.local", "w")
local_config.write("//Scripted Configure\ninclude \"/etc/bind/zones.consul\";")
local_config.close()

options_template="""
options {
        directory "/var/cache/bind";
        allow-query     { any; };
	allow-transfer  { localhost; };
        recursion yes;
        allow-recursion { any; };
        forward only;
        forwarders {
{% for forwarder in forwarders %}
			{{ forwarder }};
{% endfor %}
                };
        dnssec-validation no;
	dnssec-enable no;
        auth-nxdomain no;    # conform to RFC1035
        listen-on-v6 { any; };
};
"""
ot = Template(options_template)

if 'upstream_dns' in data:
    myfowarders = data['upstream_dns'].split(",")   
else:
    myfowarders = ['8.8.8.8', '8.8.4.4']

options_config = open("/etc/bind/named.conf.options", "w")
options_config.write(ot.render(forwarders=myfowarders))
options_config.close()