roles/named: Improve support for other zone types

Only *master* zones need zone files pre-populated, as the other types of
zones are populated by data named receives from queries and transfers.
Other types of zones require other options, however, to be usable. This
commit introduces minimal support for specifying *slave*, *forward*, and
*stub* zones.

roles/named/tasks/main.yml

@@ -40,7 +40,7 @@
     owner: root
     group: named
     force: no
-  with_items: '{{ named_zones }}'
+  with_items: '{{ named_zones|selectattr("type", "eq", "master")|list }}'
   notify: reload named
 
 - name: ensure named is configured

roles/named/templates/named.zones.j2

@@ -2,8 +2,14 @@
 {% for zone in named_zones %}
 
 zone "{{ zone.zone }}" {
-    type {{ zone.type|d('master') }};
+    type {{ zone.type }};
+{% if zone.type == 'forward' %}
+{% if zone.forward|d %}
+    forward {{ zone.forward }};
+{% endif %}
+{% else %}
     file "dynamic/{{ zone.zone }}.zone";
+{% endif %}
 {% if zone.allow_update|d %}
     allow-update {
 {% for auth in zone.allow_update %}
@@ -18,5 +24,19 @@ zone "{{ zone.zone }}" {
 {% endfor %}
     };
 {% endif %}
+{% if zone.forwarders|d %}
+    forwarders {
+{% for forwarder in zone.forwarders %}
+        {{ forwarder }};
+{% endfor %}
+    };
+{% endif %}
+{% if zone.masters|d %}
+    masters {
+{% for master in zone.masters %}
+        {{ master }};
+{% endfor %}
+    };
+{% endif %}
 };
 {% endfor %}