migration: T6007: convert all migration scripts to load as module

(cherry picked from commit 26740a8d583f64dc0a27b59dd4ae303056972c0b)

1 files changed, 65 insertions, 86 deletions

diff --git a/src/migration-scripts/system/18-to-19 b/src/migration-scripts/system/18-to-19
index fad1d17a4..5d9788d70 100755..100644
--- a/src/migration-scripts/system/18-to-19
+++ b/src/migration-scripts/system/18-to-19
@@ -1,102 +1,81 @@
-#!/usr/bin/env python3
+# Copyright 2020-2024 VyOS maintainers and contributors <maintainers@vyos.io>
 #
-# Copyright (C) 2020 VyOS maintainers and contributors
+# 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 program is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License version 2 or later as
-# published by the Free Software Foundation.
-#
-# This program is distributed in the hope that it will be useful,
+# 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 General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+# 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/>.
 
 # migrate disable-dhcp-nameservers (boolean) to name-servers-dhcp <interface>
 # if disable-dhcp-nameservers is set, just remove it
 # else retrieve all interface names that have configured dhcp(v6) address and
 # add them to the new name-servers-dhcp node
 
-from sys import argv, exit
 from vyos.ifconfig import Interface
 from vyos.configtree import ConfigTree
 
-if len(argv) < 2:
-    print("Must specify file name!")
-    exit(1)
-
-file_name = argv[1]
-
-with open(file_name, 'r') as f:
-    config_file = f.read()
-
-config = ConfigTree(config_file)
-
 base = ['system']
-if not config.exists(base):
-    # Nothing to do
-    exit(0)
-
-if config.exists(base + ['disable-dhcp-nameservers']):
-    config.delete(base + ['disable-dhcp-nameservers'])
-else:
-    dhcp_interfaces = []
-
-    # go through all interfaces searching for 'address dhcp(v6)?'
-    for sect in Interface.sections():
-        sect_base = ['interfaces', sect]
-
-        if not config.exists(sect_base):
-            continue
 
-        for intf in config.list_nodes(sect_base):
-            intf_base = sect_base + [intf]
-
-            # try without vlans
-            if config.exists(intf_base + ['address']):
-                for addr in config.return_values(intf_base + ['address']):
-                    if addr in ['dhcp', 'dhcpv6']:
-                        dhcp_interfaces.append(intf)
-
-            # try vif
-            if config.exists(intf_base + ['vif']):
-                for vif in config.list_nodes(intf_base + ['vif']):
-                    vif_base = intf_base + ['vif', vif]
-                    if config.exists(vif_base + ['address']):
-                        for addr in config.return_values(vif_base + ['address']):
-                            if addr in ['dhcp', 'dhcpv6']:
-                                dhcp_interfaces.append(f'{intf}.{vif}')
-
-            # try vif-s
-            if config.exists(intf_base + ['vif-s']):
-                for vif_s in config.list_nodes(intf_base + ['vif-s']):
-                    vif_s_base = intf_base + ['vif-s', vif_s]
-                    if config.exists(vif_s_base + ['address']):
-                        for addr in config.return_values(vif_s_base + ['address']):
-                            if addr in ['dhcp', 'dhcpv6']:
-                                dhcp_interfaces.append(f'{intf}.{vif_s}')
-
-                # try vif-c
-                if config.exists(intf_base + ['vif-c']):
-                    for vif_c in config.list_nodes(vif_s_base + ['vif-c']):
-                        vif_c_base = vif_s_base + ['vif-c', vif_c]
-                        if config.exists(vif_c_base + ['address']):
-                            for addr in config.return_values(vif_c_base + ['address']):
+def migrate(config: ConfigTree) -> None:
+    if not config.exists(base):
+        # Nothing to do
+        return
+
+    if config.exists(base + ['disable-dhcp-nameservers']):
+        config.delete(base + ['disable-dhcp-nameservers'])
+    else:
+        dhcp_interfaces = []
+
+        # go through all interfaces searching for 'address dhcp(v6)?'
+        for sect in Interface.sections():
+            sect_base = ['interfaces', sect]
+
+            if not config.exists(sect_base):
+                continue
+
+            for intf in config.list_nodes(sect_base):
+                intf_base = sect_base + [intf]
+
+                # try without vlans
+                if config.exists(intf_base + ['address']):
+                    for addr in config.return_values(intf_base + ['address']):
+                        if addr in ['dhcp', 'dhcpv6']:
+                            dhcp_interfaces.append(intf)
+
+                # try vif
+                if config.exists(intf_base + ['vif']):
+                    for vif in config.list_nodes(intf_base + ['vif']):
+                        vif_base = intf_base + ['vif', vif]
+                        if config.exists(vif_base + ['address']):
+                            for addr in config.return_values(vif_base + ['address']):
                                 if addr in ['dhcp', 'dhcpv6']:
-                                    dhcp_interfaces.append(f'{intf}.{vif_s}.{vif_c}')
-
-    # set new config nodes
-    for intf in dhcp_interfaces:
-        config.set(base + ['name-servers-dhcp'], value=intf, replace=False)
-
-try:
-    with open(file_name, 'w') as f:
-        f.write(config.to_string())
-except OSError as e:
-    print("Failed to save the modified config: {}".format(e))
-    exit(1)
-
-exit(0)
+                                    dhcp_interfaces.append(f'{intf}.{vif}')
+
+                # try vif-s
+                if config.exists(intf_base + ['vif-s']):
+                    for vif_s in config.list_nodes(intf_base + ['vif-s']):
+                        vif_s_base = intf_base + ['vif-s', vif_s]
+                        if config.exists(vif_s_base + ['address']):
+                            for addr in config.return_values(vif_s_base + ['address']):
+                                if addr in ['dhcp', 'dhcpv6']:
+                                    dhcp_interfaces.append(f'{intf}.{vif_s}')
+
+                    # try vif-c
+                    if config.exists(intf_base + ['vif-c']):
+                        for vif_c in config.list_nodes(vif_s_base + ['vif-c']):
+                            vif_c_base = vif_s_base + ['vif-c', vif_c]
+                            if config.exists(vif_c_base + ['address']):
+                                for addr in config.return_values(vif_c_base + ['address']):
+                                    if addr in ['dhcp', 'dhcpv6']:
+                                        dhcp_interfaces.append(f'{intf}.{vif_s}.{vif_c}')
+
+        # set new config nodes
+        for intf in dhcp_interfaces:
+            config.set(base + ['name-servers-dhcp'], value=intf, replace=False)