diff options
| -rw-r--r-- | data/templates/event-handler/systemd_event_handler_service.j2 | 11 | ||||
| -rw-r--r-- | interface-definitions/system-event-handler.xml.in | 27 | ||||
| -rwxr-xr-x | src/conf_mode/system_event_handler.py | 87 | ||||
| -rwxr-xr-x | src/helpers/vyos-event-handler.py | 55 |
4 files changed, 180 insertions, 0 deletions
diff --git a/data/templates/event-handler/systemd_event_handler_service.j2 b/data/templates/event-handler/systemd_event_handler_service.j2 new file mode 100644 index 000000000..da35a51c4 --- /dev/null +++ b/data/templates/event-handler/systemd_event_handler_service.j2 @@ -0,0 +1,11 @@ +[Unit] +Description=Event handler +After=network.target + +[Service] +Type=simple +Restart=always +ExecStart=/usr/bin/python3 /usr/libexec/vyos/vyos-event-handler.py --config /run/vyos-event-handler.conf + +[Install] +WantedBy=multi-user.target diff --git a/interface-definitions/system-event-handler.xml.in b/interface-definitions/system-event-handler.xml.in new file mode 100644 index 000000000..f5d8afabd --- /dev/null +++ b/interface-definitions/system-event-handler.xml.in @@ -0,0 +1,27 @@ +<?xml version="1.0" encoding="UTF-8"?> +<interfaceDefinition> + <node name="system"> + <children> + <tagNode name="event-handler" owner="${vyos_conf_scripts_dir}/system_event_handler.py"> + <properties> + <help>Event handler name</help> + </properties> + <children> + <leafNode name="pattern"> + <properties> + <help>Match pattern (regex)</help> + </properties> + </leafNode> + <leafNode name="script"> + <properties> + <help>Event handler script file</help> + <constraint> + <validator name="script"/> + </constraint> + </properties> + </leafNode> + </children> + </tagNode> + </children> + </node> +</interfaceDefinition> diff --git a/src/conf_mode/system_event_handler.py b/src/conf_mode/system_event_handler.py new file mode 100755 index 000000000..8efc816cb --- /dev/null +++ b/src/conf_mode/system_event_handler.py @@ -0,0 +1,87 @@ +#!/usr/bin/env python3 +# +# Copyright (C) 2022 VyOS maintainers and contributors +# +# 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, +# 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/>. + +import json +import os + +from vyos.config import Config +from vyos.configdict import node_changed +from vyos.util import cmd +from vyos.util import call +from vyos.template import render +from vyos import ConfigError +from vyos import airbag +airbag.enable() + + +systemd_dir = '/etc/systemd/system' +systemd_service = 'vyos-event-handler' +service_path = f'{systemd_dir}/{systemd_service}.service' +event_conf = '/run/vyos-event-handler.conf' + + +def get_config(config=None): + if config: + conf = config + else: + conf = Config() + + base = ['system', 'event-handler'] + event = conf.get_config_dict(base, get_first_key=True, no_tag_node_value_mangle=True) + + return event + +def verify(event): + # bail out early - looks like removal from running config + if not event: + return None + + for name, event_config in event.items(): + if 'pattern' not in event_config or 'script' not in event_config: + raise ConfigError(f'Event-handler "pattern and script" are mandatory!') + +def generate(event): + if not event: + return None + + conf_json = json.dumps(event, indent = 4) + with open(event_conf, 'w') as f: + f.write(conf_json) + + render(service_path, 'event-handler/systemd_event_handler_service.j2', event) + + return None + +def apply(event): + call('systemctl daemon-reload') + if event: + call(f'systemctl restart {systemd_service}.service') + else: + call(f'systemctl stop {systemd_service}.service') + + for f in [service_path, event_conf]: + if os.path.isfile(f): + os.unlink(f) + +if __name__ == '__main__': + try: + c = get_config() + verify(c) + generate(c) + apply(c) + except ConfigError as e: + print(e) + exit(1) diff --git a/src/helpers/vyos-event-handler.py b/src/helpers/vyos-event-handler.py new file mode 100755 index 000000000..018a752f4 --- /dev/null +++ b/src/helpers/vyos-event-handler.py @@ -0,0 +1,55 @@ +#!/usr/bin/env python3 +# +# Copyright (C) 2022 VyOS maintainers and contributors +# +# 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, +# 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/>. + +import argparse +import select +import re +import json + +from sys import argv +from os import getpid +from systemd import journal +from vyos.util import call + + +parser = argparse.ArgumentParser() +parser.add_argument("-c", "--config", action="store", help="Path to even-handler configuration", required=True) + +args = parser.parse_args() +config = args.config +data = journal.Reader() +data.seek_tail() +data.get_previous() +p = select.poll() +p.register(data, data.get_events()) +my_pid = getpid() + +with open(config, 'r') as f: + config = json.load(f) + + +if __name__ == '__main__': + while p.poll(): + if data.process() != journal.APPEND: + continue + for entry in data: + message = entry['MESSAGE'] + for name, event_config in config.items(): + pattern = re.compile(rf'{event_config["pattern"]}') + script = event_config['script'] + if message != "" and entry['_PID'] != my_pid and pattern.match(message): + call(script) + journal.send(f'Pattern found: {event_config["pattern"]}, script executed: {script}') |