Modified keahook.py to update PowerDNS for host reservation changes

docker/kea/Dockerfile

@@ -17,6 +17,7 @@ RUN set -eux; \
         socat \
         python3 \
         python3-pip \
+        python3-requests \
         libpq5 \
         libmariadb3 \
         libpython3.11 \
@@ -58,7 +59,7 @@ RUN set -eux; \
         --disable-rpath \
         --enable-generate-parser \
         --without-werror; \
-    make -j; \
+    make; \
     make install
 
 # Install kea_python https://github.com/invite-networks/kea_python

docker/kea/keahook.py

@@ -1,5 +1,14 @@
+from os import environ
 import kea
+import json
+import requests
 
+powerdns_domain = environ["PDNS_DOMAIN"]
+powerdns_api_key = environ["PDNS_API_KEY"]
+powerdns_api_host = environ["PDNS_API_HOST"]
+powerdns_api_port = environ["PDNS_API_PORT"]
+powerdns_api_protocol = environ["PDNS_API_PROTOCOL"]
+powerdns_api_url = f"{powerdns_api_protocol}://{powerdns_api_host}:{powerdns_api_port}/api/v1"
 
 class UNSPECIFIED:
     pass
@@ -66,6 +75,91 @@ def wrap_handler(handle, get_response):
         return 1
     return 0
 
+# Add dns record to PowerDNS via its API
+def add_dns_record(host_ip, hostname):
+    headers = {'X-API-Key': powerdns_api_key}
+    payload = {
+        "rrsets": [
+            {
+                "name": f"{hostname}.",
+                "type": "A",
+                "ttl": 600,
+                "changetype": "REPLACE",
+                "records": [
+                    {
+                        "content": host_ip,
+                        "disabled": False
+                    }
+                ]
+            }
+        ]
+    }
+
+    response = requests.patch(
+        f"{powerdns_api_url}/servers/localhost/zones/{powerdns_domain}.",
+        headers=headers,
+        data=json.dumps(payload)
+    )
+
+    if response.status_code not in [200, 201, 204]:
+        raise Exception(f"Failed to add DNS record: {response.content}")
+
+# Delete dns record from PowerDNS via its API
+def delete_dns_record(hostname):
+    headers = { 'X-API-Key': powerdns_api_key }
+
+    data = {
+        "rrsets": [
+            {
+                "name": f"{hostname}.{powerdns_domain}.",
+                "type": "A",
+                "changetype": "DELETE"
+            }
+        ]
+    }
+
+    response = requests.patch(
+        f"{powerdns_api_url}/servers/localhost/zones/{powerdns_domain}.",
+        headers=headers,
+        data=json.dumps(data)
+    )
+
+    if response.status_code not in [200, 204]:
+        raise Exception(f"Failed to delete DNS record: {response.content}")
+
+
+def core_add_reservation(subnet_id, resv, host_mgr):
+    unsupported_arguments = [ 'identifier-type' ]
+    # Remove any unsupported keys from the reservation dictionary
+    for key in unsupported_arguments:
+        resv.pop(key, None)
+    host = kea.HostReservationParser4().parse(subnet_id, resv)
+    host_mgr.add(host)
+    ip_address = resv.get('ip-address')
+    hostname = resv.get('hostname')
+    fqdn = f"{hostname}.{powerdns_domain}"
+    try:
+        add_dns_record(ip_address, fqdn)
+    except Exception as e:
+        return {'result': 1, 'text': f"Failed to add DNS record: {e}"}
+    return {'result': 0, 'text': f"Host reservation added: MAC={resv.get('hw-address')}, IP={ip_address}"}
+
+def core_del_reservation(subnet_id, args, host_mgr):
+    identifier_type = args.get('identifier-type')
+    # Explicitly get 'identifier' or 'hw-address'
+    identifier = args.get('identifier') or args.get('hw-address')
+    if identifier is None:
+        return {'result': 1, 'text': f"Identifier not provided for identifier type {identifier_type}"}
+
+    was_deleted = host_mgr.del4(subnet_id, identifier_type, identifier)
+    if was_deleted:
+        hostname = args.get('hostname')
+        try:
+            delete_dns_record(hostname)
+        except Exception as e:
+            return {'result': 1, 'text': f"Failed to delete DNS record: {e}"}
+        return {'result': 0, 'text': 'Host deleted.'}
+    return {'result': 1, 'text': 'Host not deleted (not found).'}
 
 # {"command": "reservation-add",
 #  "arguments": {"reservation": {"subnet-id": 1,
@@ -75,11 +169,8 @@ def get_response(args):
         resv = get_map_arg(args, 'reservation')
         subnet_id = get_int_arg(resv, 'subnet-id')
         del resv['subnet-id']
-        host = kea.HostReservationParser4().parse(subnet_id, resv)
-        kea.HostMgr.instance().add(host)
-        return {'result': 0,
-                'text': 'Host added.'}
-
+        host_mgr = kea.HostMgr.instance()
+        return core_add_reservation(subnet_id, resv, host_mgr)
     return wrap_handler(handle, get_response)
 
 
@@ -164,18 +255,33 @@ def get_response(args):
 #                "identifier": "01:02:03:04:05:06"}}
 def reservation_del(handle):
     def get_response(args):
-        host_mgr = kea.HostMgr.instance()
         subnet_id = get_int_arg(args, 'subnet-id')
-        if 'ip-address' in args:
-            ip_address = get_string_arg(args, 'ip-address')
-            was_deleted = host_mgr.del_(subnet_id, ip_address)
-        else:
-            identifier_type = get_string_arg(args, 'identifier-type')
-            identifier = get_string_arg(args, 'identifier')
-            was_deleted = host_mgr.del4(subnet_id, identifier_type, identifier)
-        if was_deleted:
-            return {'result': 0, 'text': 'Host deleted.'}
-        return {'result': 1, 'text': 'Host not deleted (not found).'}
+        host_mgr = kea.HostMgr.instance()
+        return core_del_reservation(subnet_id, args, host_mgr)
+    return wrap_handler(handle, get_response)
+
+def reservation_update(handle):
+    def get_response(args):
+        resv = get_map_arg(args, 'reservation')
+        subnet_id = get_int_arg(resv, 'subnet-id')
+        del resv['subnet-id']
+        host_mgr = kea.HostMgr.instance()
+
+        hw_address = resv.get('hw-address')
+        if hw_address is None:
+            return {'result': 1, 'text': 'hw-address not provided'}
+
+        # Ensure that hw_address is a string
+        if not isinstance(hw_address, str):
+            return {'result': 1, 'text': 'hw-address must be a string'}
+
+        # First delete the old reservation
+        del_response = core_del_reservation(subnet_id, {'identifier-type': 'hw-address', 'identifier': hw_address}, host_mgr)
+        if del_response['result'] != 0:
+            return del_response
+
+        # Then add the new reservation
+        return core_add_reservation(subnet_id, resv, host_mgr)
 
     return wrap_handler(handle, get_response)
 
@@ -186,4 +292,5 @@ def load(handle):
     handle.registerCommandCallout('reservation-get-all', reservation_get_all)
     handle.registerCommandCallout('reservation-get-page', reservation_get_page)
     handle.registerCommandCallout('reservation-del', reservation_del)
+    handle.registerCommandCallout('reservation_update', reservation_update)
     return 0