dns: forwarding: T2921: migrate to get_config_dict()

1 files changed, 62 insertions, 110 deletions

diff --git a/src/conf_mode/dns_forwarding.py b/src/conf_mode/dns_forwarding.py
index d6eb76d91..5101c1e79 100755
--- a/src/conf_mode/dns_forwarding.py
+++ b/src/conf_mode/dns_forwarding.py
@@ -17,14 +17,17 @@
 import os
 
 from sys import exit
-from copy import deepcopy
 
 from vyos.config import Config
+from vyos.configdict import dict_merge
 from vyos.hostsd_client import Client as hostsd_client
-from vyos import ConfigError
-from vyos.util import call, chown
+from vyos.util import call
+from vyos.util import chown
+from vyos.util import vyos_dict_search
 from vyos.template import render
+from vyos.xml import defaults
 
+from vyos import ConfigError
 from vyos import airbag
 airbag.enable()
 
@@ -35,116 +38,63 @@ pdns_rec_hostsd_lua_conf_file = f'{pdns_rec_run_dir}/recursor.vyos-hostsd.conf.l
 pdns_rec_hostsd_zones_file = f'{pdns_rec_run_dir}/recursor.forward-zones.conf'
 pdns_rec_config_file = f'{pdns_rec_run_dir}/recursor.conf'
 
-default_config_data = {
-    'allow_from': [],
-    'cache_size': 10000,
-    'export_hosts_file': 'yes',
-    'listen_address': [],
-    'name_servers': [],
-    'negative_ttl': 3600,
-    'system': False,
-    'domains': {},
-    'dnssec': 'process-no-validate',
-    'dhcp_interfaces': []
-}
-
 hostsd_tag = 'static'
 
-def get_config(conf):
-    dns = deepcopy(default_config_data)
+def get_config(config=None):
+    if config:
+        conf = config
+    else:
+        conf = Config()
     base = ['service', 'dns', 'forwarding']
-
     if not conf.exists(base):
         return None
 
-    conf.set_level(base)
-
-    if conf.exists(['allow-from']):
-        dns['allow_from'] = conf.return_values(['allow-from'])
-
-    if conf.exists(['cache-size']):
-        cache_size = conf.return_value(['cache-size'])
-        dns['cache_size'] = cache_size
-
-    if conf.exists('negative-ttl'):
-        negative_ttl = conf.return_value(['negative-ttl'])
-        dns['negative_ttl'] = negative_ttl
-
-    if conf.exists(['domain']):
-        for domain in conf.list_nodes(['domain']):
-            conf.set_level(base + ['domain', domain])
-            entry = {
-                'nslist': bracketize_ipv6_addrs(conf.return_values(['server'])),
-                'addNTA': conf.exists(['addnta']),
-                'recursion-desired': conf.exists(['recursion-desired'])
-            }
-            dns['domains'][domain] = entry
-
-        conf.set_level(base)
+    dns = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True)
+    # We have gathered the dict representation of the CLI, but there are default
+    # options which we need to update into the dictionary retrived.
+    default_values = defaults(base)
+    dns = dict_merge(default_values, dns)
 
-    if conf.exists(['ignore-hosts-file']):
-        dns['export_hosts_file'] = "no"
+    # some additions to the default dictionary
+    if 'system' in dns:
+        base_nameservers = ['system', 'name-server']
+        if conf.exists(base_nameservers):
+            dns.update({'system_name_server': conf.return_values(base_nameservers)})
 
-    if conf.exists(['name-server']):
-        dns['name_servers'] = bracketize_ipv6_addrs(
-                conf.return_values(['name-server']))
-
-    if conf.exists(['system']):
-        dns['system'] = True
-
-    if conf.exists(['listen-address']):
-        dns['listen_address'] = conf.return_values(['listen-address'])
-
-    if conf.exists(['dnssec']):
-        dns['dnssec'] = conf.return_value(['dnssec'])
-
-    if conf.exists(['dhcp']):
-        dns['dhcp_interfaces'] = conf.return_values(['dhcp'])
+        base_nameservers_dhcp = ['system', 'name-servers-dhcp']
+        if conf.exists(base_nameservers_dhcp):
+            dns.update({'system_name_server_dhcp': conf.return_values(base_nameservers_dhcp)})
 
     return dns
 
-def bracketize_ipv6_addrs(addrs):
-    """Wraps each IPv6 addr in addrs in [], leaving IPv4 addrs untouched."""
-    return ['[{0}]'.format(a) if a.count(':') > 1 else a for a in addrs]
-
-def verify(conf, dns):
+def verify(dns):
     # bail out early - looks like removal from running config
-    if dns is None:
+    if not dns:
         return None
 
-    if not dns['listen_address']:
-        raise ConfigError(
-            "Error: DNS forwarding requires a listen-address")
-
-    if not dns['allow_from']:
-        raise ConfigError(
-                "Error: DNS forwarding requires an allow-from network")
-
-    if dns['domains']:
-        for domain in dns['domains']:
-            if not dns['domains'][domain]['nslist']:
-                raise ConfigError((
-                    f'Error: No server configured for domain {domain}'))
-
-    no_system_nameservers = False
-    conf.set_level([])
-    if dns['system'] and not (
-            conf.exists(['system', 'name-server']) or
-            conf.exists(['system', 'name-servers-dhcp']) ):
-        no_system_nameservers = True
-        print(("DNS forwarding warning: No 'system name-server' or "
-                "'system name-servers-dhcp' set\n"))
-
-    if (no_system_nameservers or not dns['system']) and not (
-            dns['name_servers'] or dns['dhcp_interfaces']):
-        print(("DNS forwarding warning: No 'dhcp', 'name-server' or 'system' "
-            "nameservers set. Forwarding will operate as a recursor.\n"))
+    if 'listen_address' not in dns:
+        raise ConfigError('DNS forwarding requires a listen-address')
+
+    if 'allow_from' not in dns:
+        raise ConfigError('DNS forwarding requires an allow-from network')
+
+    # we can not use vyos_dict_search() when testing for domain servers
+    # as a domain will contains dot's which is out dictionary delimiter.
+    if 'domain' in dns:
+        for domain in dns['domain']:
+            if 'server' not in dns['domain'][domain]:
+                raise ConfigError(f'No server configured for domain {domain}!')
+
+    if 'system' in dns:
+        if not ('system_name_server' in dns or 'system_name_server_dhcp' in dns):
+            print("Warning: No 'system name-server' or 'system " \
+                  "name-servers-dhcp' configured")
 
     return None
 
 def generate(dns):
     # bail out early - looks like removal from running config
-    if dns is None:
+    if not dns:
         return None
 
     render(pdns_rec_config_file, 'dns-forwarding/recursor.conf.tmpl',
@@ -154,17 +104,18 @@ def generate(dns):
             dns, trim_blocks=True, user=pdns_rec_user, group=pdns_rec_group)
 
     # if vyos-hostsd didn't create its files yet, create them (empty)
-    for f in [pdns_rec_hostsd_lua_conf_file, pdns_rec_hostsd_zones_file]:
-        with open(f, 'a'):
+    for file in [pdns_rec_hostsd_lua_conf_file, pdns_rec_hostsd_zones_file]:
+        with open(file, 'a'):
             pass
-        chown(f, user=pdns_rec_user, group=pdns_rec_group)
+        chown(file, user=pdns_rec_user, group=pdns_rec_group)
 
     return None
 
 def apply(dns):
-    if dns is None:
+    if not dns:
         # DNS forwarding is removed in the commit
-        call("systemctl stop pdns-recursor.service")
+        call('systemctl stop pdns-recursor.service')
+
         if os.path.isfile(pdns_rec_config_file):
             os.unlink(pdns_rec_config_file)
     else:
@@ -174,8 +125,8 @@ def apply(dns):
         # add static nameservers to hostsd so they can be joined with other
         # sources
         hc.delete_name_servers([hostsd_tag])
-        if dns['name_servers']:
-            hc.add_name_servers({hostsd_tag: dns['name_servers']})
+        if 'name_server' in dns:
+            hc.add_name_servers({hostsd_tag: dns['name_server']})
 
         # delete all nameserver tags
         hc.delete_name_server_tags_recursor(hc.get_name_server_tags_recursor())
@@ -184,32 +135,33 @@ def apply(dns):
         # our own tag (static)
         hc.add_name_server_tags_recursor([hostsd_tag])
 
-        if dns['system']:
+        if 'system' in dns:
             hc.add_name_server_tags_recursor(['system'])
         else:
             hc.delete_name_server_tags_recursor(['system'])
 
         # add dhcp nameserver tags for configured interfaces
-        for intf in dns['dhcp_interfaces']:
-            hc.add_name_server_tags_recursor(['dhcp-' + intf, 'dhcpv6-' + intf ])
+        if 'system_name_server_dhcp' in dns:
+            for interface in dns['system_name_server_dhcp']:
+                hc.add_name_server_tags_recursor(['dhcp-' + interface,
+                                                  'dhcpv6-' + interface ])
 
         # hostsd will generate the forward-zones file
         # the list and keys() are required as get returns a dict, not list
         hc.delete_forward_zones(list(hc.get_forward_zones().keys()))
-        if dns['domains']:
-            hc.add_forward_zones(dns['domains'])
+        if 'domain' in dns:
+            hc.add_forward_zones(dns['domain'])
 
         # call hostsd to generate forward-zones and its lua-config-file
         hc.apply()
 
         ### finally (re)start pdns-recursor
-        call("systemctl restart pdns-recursor.service")
+        call('systemctl restart pdns-recursor.service')
 
 if __name__ == '__main__':
     try:
-        conf = Config()
-        c = get_config(conf)
-        verify(conf, c)
+        c = get_config()
+        verify(c)
         generate(c)
         apply(c)
     except ConfigError as e: