diff -r 1e925a1cc8de -r 600ad9eb6f25 pvl/hosts/zone.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/pvl/hosts/zone.py	Tue Feb 24 21:38:12 2015 +0200
@@ -0,0 +1,251 @@
+"""
+    Generate zonefile records from hosts
+"""
+
+import ipaddr
+import logging; log = logging.getLogger('pvl.hosts.zone')
+import pvl.dns
+
+class HostZoneError(Exception):
+    pass
+
+def resolve (origin, domain, name) :
+    """
+        Resolve relative CNAME for label@origin -> alias@domain
+    """
+
+    fqdn = pvl.dns.join(name, domain)
+
+    if not origin:
+        return fqdn
+
+    elif domain == origin:
+         return name
+
+    elif fqdn.endswith('.' + origin):
+        return pvl.dns.relative(origin, fqdn)
+
+    elif domain:
+        raise HostZoneError("{name}: domain {domain} out of zone {origin}".format(name=name, domain=domain, origin=origin))
+
+    else:
+        raise HostZoneError("{name}: fqdn {fqdn} out of zone {origin}".format(name=name, fqdn=fqdn, origin=origin))
+
+def host_forward (host, origin) :
+    """
+        Yield ZoneRecords for hosts within the given zone origin
+    """
+
+    try:
+        label = resolve(origin, host.domain, host.name)
+    except HostZoneError as error:
+        log.info("%s: skip: %s", host, error)
+        return
+
+    if host.forward:
+        forward = pvl.dns.zone.fqdn(host.forward)
+
+        log.info("%s: forward: %s", host, forward)
+
+        yield pvl.dns.ZoneRecord.CNAME(label, forward)
+        return
+
+    elif host.forward is not None:
+        log.info("%s: skip forward", host)
+        return
+    
+    # forward
+    if host.ip :
+        yield pvl.dns.ZoneRecord.A(label, host.ip)
+
+    if host.ip6 :
+        yield pvl.dns.ZoneRecord.AAAA(label, host.ip6)
+
+    if host.location:
+        location_alias, location_domain = host.location
+
+        if not location_domain:
+            location_domain = host.domain
+
+        yield pvl.dns.ZoneRecord.CNAME(resolve(origin, location_domain, location_alias), label)
+
+    for alias in host.alias4:
+        yield pvl.dns.ZoneRecord.CNAME(resolve(origin, host.domain, alias), label)
+
+    for alias in host.alias4:
+        yield pvl.dns.ZoneRecord.A(resolve(origin, host.domain, alias), host.ip)
+
+    for alias in host.alias6:
+         yield pvl.dns.ZoneRecord.AAAA(resolve(origin, host.domain, alias), host.ip6)
+
+def host_reverse (host, prefix) :
+    """
+        Yield (ip, fqnd) for host within given prefix.
+    """
+
+    if prefix.version == 4 :
+        ip = host.ip
+    elif prefix.version == 6 :
+        ip = host.ip6
+    else :
+        raise ValueError("%s: unknown ip version: %s" % (prefix, prefix.version))
+
+    if not ip :
+        log.debug("%s: no ip%d", host, prefix.version)
+        return
+
+    if ip not in prefix :
+        log.debug("%s: %s out of prefix: %s", host, ip, prefix)
+        return
+    
+    # relative label
+    label = pvl.dns.reverse_label(prefix, ip)
+   
+    if host.reverse :
+        alias = pvl.dns.zone.fqdn(host.reverse)
+        
+        log.info("%s %s[%s]: CNAME %s", host, prefix, ip, alias)
+
+        yield ip, pvl.dns.zone.ZoneRecord.CNAME(label, alias)
+
+    elif host.reverse is None :
+        fqdn = host.fqdn()
+
+        log.info("%s %s[%s]: PTR %s", host, prefix, ip, fqdn)
+
+        yield ip, pvl.dns.zone.ZoneRecord.PTR(label, fqdn)
+
+    else :
+        log.info("%s %s[%s]: omit", host, prefix, ip)
+ 
+def apply_hosts_forward (options, hosts, origin) :
+    """
+        Generate DNS ZoneRecords for for hosts within the given zone origin.
+
+        Yields ZoneRecords in Host-order
+    """
+
+    if options.add_origin :
+        yield pvl.dns.ZoneDirective.build(None, 'ORIGIN', origin)
+
+    by_name = dict()
+    by_cname = dict()
+    
+    for host in hosts:
+        if not host.domain:
+            log.debug("%s: skip without domain", host)
+
+        for rr in host_forward(host, origin) :
+            if rr.name in by_cname:
+                raise HostZoneError(host, "{host}: CNAME {cname} conflict: {rr}".format(host=host, cname=by_cname[rr.name].name, rr=rr))
+            elif rr.type == 'CNAME' and rr.name in by_name:
+                raise HostZoneError(host, "{host}: CNAME {cname} conflict: {rr}".format(host=host, cname=rr.name, rr=by_name[rr.name]))
+            
+            by_name[rr.name] = rr
+
+            if rr.type == 'CNAME':
+                by_cname[rr.name] = rr
+            
+            # preserve ordering
+            yield rr
+
+def apply_hosts_reverse (options, hosts, prefix) :
+    """
+        Generate DNS ZoneRecords within the given prefix's reverse-dns zone for hosts.
+
+        Yields ZoneRecords in IPAddress-order
+    """
+    
+    # collect data for records
+    by_ip = dict()
+
+    for host in hosts:
+        for ip, rr in host_reverse(host, prefix) :
+            if ip in by_ip :
+                raise HostZoneError(host, "{host}: IP {ip} conflict: {other}".format(host=host, ip=ip, other=by_ip[ip]))
+            
+            # do not retain order
+            by_ip[ip] = rr
+
+    if options.unknown_host :
+        # enumerate all of them
+        iter_ips = prefix.iterhosts()
+    else :
+        iter_ips = sorted(by_ip)
+
+    for ip in iter_ips :
+        if ip in by_ip :
+            yield by_ip[ip]
+
+        elif options.unknown_host:
+            # synthesize a record
+            label = pvl.dns.reverse_label(prefix, ip)
+            fqdn = pvl.dns.zone.fqdn(options.unknown_host, options.hosts_domain)
+
+            log.info("%s %s[%s]: unused PTR %s", options.unknown_host, ip, prefix, fqdn)
+
+            yield pvl.dns.zone.ZoneRecord.PTR(label, fqdn)
+
+        else :
+            continue
+
+import pvl.args
+import pvl.hosts.config
+
+import optparse 
+
+def forward_main () :
+    """
+        Generate bind zonefiles from host definitions.
+    """
+
+    parser = optparse.OptionParser(forward_main.__doc__)
+    parser.add_option_group(pvl.args.parser(parser))
+    parser.add_option_group(pvl.hosts.config.optparser(parser))
+
+    parser.add_option('--add-origin',           action='store_true',
+            help="Include $ORIGIN directive in zone")
+
+    parser.add_option('--forward-zone',         metavar='DOMAIN',
+            help="Generate forward zone for domain")
+
+    # input
+    options, args = parser.parse_args()
+    
+    pvl.args.apply(options)
+
+    hosts = pvl.hosts.apply(options, args)
+
+    # process
+    for rr in apply_hosts_forward(options, hosts, options.forward_zone):
+        print unicode(rr)
+    
+    return 0
+
+def reverse_main () :
+    """
+        Generate bind zonefiles from host definitions.
+    """
+
+    parser = optparse.OptionParser(reverse_main.__doc__)
+    parser.add_option_group(pvl.args.parser(parser))
+    parser.add_option_group(pvl.hosts.config.optparser(parser))
+
+    parser.add_option('--reverse-zone',         metavar='PREFIX',
+            help="Generate reverse zone for prefix")
+
+    parser.add_option('--unknown-host',         metavar='NAME',
+            help="Generate records for unused IPs")
+
+    # input
+    options, args = parser.parse_args()
+    
+    pvl.args.apply(options)
+
+    hosts = pvl.hosts.apply(options, args)
+
+    # process
+    for rr in apply_hosts_reverse(options, hosts, pvl.dns.parse_prefix(options.reverse_zone)):
+        print unicode(rr)
+
+    return 0