dhcp: T6102: Fix clear DHCP lease op-mode

* Add `clear dhcpv6-server lease`
* Standardize using vyos.opmode

2 files changed, 23 insertions, 88 deletions

diff --git a/src/op_mode/clear_dhcp_lease.py b/src/op_mode/clear_dhcp_lease.py
deleted file mode 100755
index 7d4b47104..000000000
--- a/src/op_mode/clear_dhcp_lease.py
+++ /dev/null
@@ -1,88 +0,0 @@
-#!/usr/bin/env python3
-#
-# Copyright 2023 VyOS maintainers and contributors <maintainers@vyos.io>
-#
-# This library is free software; you can redistribute it and/or
-# modify it under the terms of the GNU Lesser General Public
-# License as published by the Free Software Foundation; either
-# version 2.1 of the License, or (at your option) any later version.
-#
-# This library is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-# Lesser General Public License for more details.
-#
-# You should have received a copy of the GNU Lesser General Public
-# License along with this library.  If not, see <http://www.gnu.org/licenses/>.
-
-import argparse
-import re
-
-from vyos.configquery import ConfigTreeQuery
-from vyos.kea import kea_parse_leases
-from vyos.utils.io import ask_yes_no
-from vyos.utils.process import call
-from vyos.utils.commit import commit_in_progress
-
-# TODO: Update to use Kea control socket command "lease4-del"
-
-config = ConfigTreeQuery()
-base = ['service', 'dhcp-server']
-lease_file = '/config/dhcp/dhcp4-leases.csv'
-
-
-def del_lease_ip(address):
-    """
-    Read lease_file and write data to this file
-    without specific section "lease ip"
-    Delete section "lease x.x.x.x { x;x;x; }"
-    """
-    with open(lease_file, encoding='utf-8') as f:
-        data = f.read().rstrip()
-        pattern = rf"^{address},[^\n]+\n"
-        # Delete lease for ip block
-        data = re.sub(pattern, '', data)
-
-    # Write new data to original lease_file
-    with open(lease_file, 'w', encoding='utf-8') as f:
-        f.write(data)
-
-def is_ip_in_leases(address):
-    """
-    Return True if address found in the lease file
-    """
-    leases = kea_parse_leases(lease_file)
-    for lease in leases:
-        if address == lease['address']:
-            return True
-    print(f'Address "{address}" not found in "{lease_file}"')
-    return False
-
-if not config.exists(base):
-    print('DHCP-server not configured!')
-    exit(0)
-
-if config.exists(base + ['failover']):
-    print('Lease cannot be reset in failover mode!')
-    exit(0)
-
-
-if __name__ == '__main__':
-    parser = argparse.ArgumentParser()
-    parser.add_argument('--ip', help='IPv4 address', action='store', required=True)
-
-    args = parser.parse_args()
-    address = args.ip
-
-    if not is_ip_in_leases(address):
-        exit(1)
-
-    if commit_in_progress():
-        print('Cannot clear DHCP lease while a commit is in progress')
-        exit(1)
-
-    if not ask_yes_no(f'This will restart DHCP server.\nContinue?'):
-        exit(1)
-    else:
-        del_lease_ip(address)
-        call('systemctl restart kea-dhcp4-server.service')
diff --git a/src/op_mode/dhcp.py b/src/op_mode/dhcp.py
index 1d9ad0e76..d27e1baf7 100755
--- a/src/op_mode/dhcp.py
+++ b/src/op_mode/dhcp.py
@@ -31,6 +31,7 @@ from vyos.configquery import ConfigTreeQuery
 from vyos.kea import kea_get_active_config
 from vyos.kea import kea_get_leases
 from vyos.kea import kea_get_pool_from_subnet_id
+from vyos.kea import kea_delete_lease
 from vyos.utils.process import is_systemd_service_running
 
 time_string = "%a %b %d %H:%M:%S %Z %Y"
@@ -360,6 +361,28 @@ def show_server_static_mappings(raw: bool, family: ArgFamily, pool: typing.Optio
     else:
         return _get_formatted_server_static_mappings(static_mappings, family=family)
 
+def _lease_valid(inet, address):
+    leases = kea_get_leases(inet)
+    for lease in leases:
+        if address == lease['ip-address']:
+            return True
+    return False
+
+@_verify
+def clear_dhcp_server_lease(family: ArgFamily, address: str):
+    v = 'v6' if family == 'inet6' else ''
+    inet = '6' if family == 'inet6' else '4'
+
+    if not _lease_valid(inet, address):
+        print(f'Lease not found on DHCP{v} server')
+        return None
+
+    if not kea_delete_lease(inet, address):
+        print(f'Failed to clear lease for "{address}"')
+        return None
+
+    print(f'Lease "{address}" has been cleared')
+
 def _get_raw_client_leases(family='inet', interface=None):
     from time import mktime
     from datetime import datetime