#!/usr/bin/env python

# Splice TinyDNS validator and uploader
# David North, August 2009

import os, sys, glob

## Configuration
user = 'david' #os.getenv('USERV_USER')
datadir= '/home/david/Desktop/data'  #'/etc/bmdns/data'
userdatadir='/home/' + user + '/dns'
zonelist= '/home/david/Desktop/zonelist'  #'/etc/bmdns/zonelist'
## End configuration

def validate(line, line_number, file):
    """
    Validate a TinyDNS line.
    TinyDNS record types (id'd by first char of line) are:
        6=ipv6+rDNS, +=host, .=authority, @=mx, C=cname, &=ns
        '=txt, _=generic (e.g. SRV), Z=soa, 3=6 with no rDNS
    """
    def die(msg):
        """Conk out with 'error on line x' + msg"""
        sys.stderr.write('Error on line %s of %s: %s\n', line_number, file, msg)
        sys.stderr.write('Upload aborted. Please fix the error above.\n')
        sys.exit(1)

    if not line:
        return # blank lines are ignored
    else:
        first = line[0]
        if first == '#':
            return # comments are ignored, so they're fine too
        elif first == '6':
            # IPv6 + rDNS: must not be for an IP in another splicer's range, 
            # and hostname must be in one of user's domains
        elif first == '3':
            #same as 6, but range restriction not needed as no automatic rDNS insertion
        elif first == '.':
            # rDNS authority: allowed for david and rdns only respectively, as they handle it for v4 and v6
        elif first == '@':
            # MX record. If it's for the splice MX, only david should give the IP, and it should be the right one
        elif first in ['C', "'", '+', '_']: 
            # CNAME, TXT, A and custom (SRV, etc.)
            # hostname must be in one of user's domains
        elif first in ['Z', '&']: 
            # SOA and NS
            die("SOA and NS records are not implemented, because David didn't see the need. Email him and tell him not to be a lazy so-and-so.")
        else:
            die('Unsupported record type. Please speak to David.')

# check the contents of the user's ~/dns/ folder for sanity
# ignore files with names ending .old .ctold ~ 
files = [f for f in os.listdir(userdatadir) if not f.endswith('~') and not f.endswith('.old') and not f.endswith('.ctold')]
paths = [os.path.join(datadir, f) for f in files]

for fp in paths:
    f = open(fp, 'r')
    line_number = 0
    for line in f:
        validate(l.strip(), line_number, fp) # exits script with error if appropriate
        line_number += 1

# If we've reached this point, the data is good, so copy it to the datadir and push it to the servers

# delete any previous data for this user
for f in glob.glob(os.path.join(datadir, user) + '-*')
    os.unlink(f)

for f in files:
    os.copy
    cp $userdatadir/$fn $datadir/$USERV_USER-$fn

# run the Bytemark upload script
os.chdir(datadir)
./upload