firewall: T4821: add support for adding conf_mode script dependencies

1 files changed, 65 insertions, 0 deletions

diff --git a/python/vyos/configdep.py b/python/vyos/configdep.py
new file mode 100644
index 000000000..e6b82ca93
--- /dev/null
+++ b/python/vyos/configdep.py
@@ -0,0 +1,65 @@
+# Copyright 2022 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 os
+from inspect import stack
+
+from vyos.util import load_as_module
+
+dependents = {}
+
+def canon_name(name: str) -> str:
+    return os.path.splitext(name)[0].replace('-', '_')
+
+def canon_name_of_path(path: str) -> str:
+    script = os.path.basename(path)
+    return canon_name(script)
+
+def caller_name() -> str:
+    return stack()[-1].filename
+
+def run_config_mode_script(script: str, config):
+    from vyos.defaults import directories
+
+    path = os.path.join(directories['conf_mode'], script)
+    name = canon_name(script)
+    mod = load_as_module(name, path)
+
+    config.set_level([])
+    try:
+        c = mod.get_config(config)
+        mod.verify(c)
+        mod.generate(c)
+        mod.apply(c)
+    except (VyOSError, ConfigError) as e:
+        raise ConfigError(repr(e))
+
+def def_closure(script: str, config):
+    def func_impl():
+        run_config_mode_script(script, config)
+    return func_impl
+
+def set_dependent(target: str, config):
+    k = canon_name_of_path(caller_name())
+    l = dependents.setdefault(k, [])
+    func = def_closure(target, config)
+    l.append(func)
+
+def call_dependents():
+    k = canon_name_of_path(caller_name())
+    l = dependents.get(k, [])
+    while l:
+        f = l.pop(0)
+        f()