Merge pull request #1358 from sever-sever/T1237

routing: T1237: Add new feature failover route

1 files changed, 121 insertions, 0 deletions

diff --git a/src/conf_mode/protocols_failover.py b/src/conf_mode/protocols_failover.py
new file mode 100755
index 000000000..048ba7a89
--- /dev/null
+++ b/src/conf_mode/protocols_failover.py
@@ -0,0 +1,121 @@
+#!/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
+
+from pathlib import Path
+
+from vyos.config import Config
+from vyos.configdict import dict_merge
+from vyos.template import render
+from vyos.util import call
+from vyos.xml import defaults
+from vyos import ConfigError
+from vyos import airbag
+
+airbag.enable()
+
+
+service_name = 'vyos-failover'
+service_conf = Path(f'/run/{service_name}.conf')
+systemd_service = '/etc/systemd/system/vyos-failover.service'
+rt_proto_failover = '/etc/iproute2/rt_protos.d/failover.conf'
+
+
+def get_config(config=None):
+    if config:
+        conf = config
+    else:
+        conf = Config()
+
+    base = ['protocols', 'failover']
+    failover = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True)
+
+    # Set default values only if we set config
+    if failover.get('route'):
+        for route, route_config in failover.get('route').items():
+            for next_hop, next_hop_config in route_config.get('next_hop').items():
+                default_values = defaults(base + ['route'])
+                failover['route'][route]['next_hop'][next_hop] = dict_merge(
+                    default_values['next_hop'], failover['route'][route]['next_hop'][next_hop])
+
+    return failover
+
+def verify(failover):
+    # bail out early - looks like removal from running config
+    if not failover:
+        return None
+
+    if 'route' not in failover:
+        raise ConfigError(f'Failover "route" is mandatory!')
+
+    for route, route_config in failover['route'].items():
+        if not route_config.get('next_hop'):
+            raise ConfigError(f'Next-hop for "{route}" is mandatory!')
+
+        for next_hop, next_hop_config in route_config.get('next_hop').items():
+            if 'interface' not in next_hop_config:
+                raise ConfigError(f'Interface for route "{route}" next-hop "{next_hop}" is mandatory!')
+
+            if not next_hop_config.get('check'):
+                raise ConfigError(f'Check target for next-hop "{next_hop}" is mandatory!')
+
+            if 'target' not in next_hop_config['check']:
+                raise ConfigError(f'Check target for next-hop "{next_hop}" is mandatory!')
+
+            check_type = next_hop_config['check']['type']
+            if check_type == 'tcp' and 'port' not in next_hop_config['check']:
+                raise ConfigError(f'Check port for next-hop "{next_hop}" and type TCP is mandatory!')
+
+    return None
+
+def generate(failover):
+    if not failover:
+        service_conf.unlink(missing_ok=True)
+        return None
+
+    # Add own rt_proto 'failover'
+    # Helps to detect all own routes 'proto failover'
+    with open(rt_proto_failover, 'w') as f:
+        f.write('111  failover\n')
+
+    # Write configuration file
+    conf_json = json.dumps(failover, indent=4)
+    service_conf.write_text(conf_json)
+    render(systemd_service, 'protocols/systemd_vyos_failover_service.j2', failover)
+
+    return None
+
+def apply(failover):
+    if not failover:
+        call(f'systemctl stop {service_name}.service')
+        call('ip route flush protocol failover')
+    else:
+        call('systemctl daemon-reload')
+        call(f'systemctl restart {service_name}.service')
+        call(f'ip route flush protocol failover')
+
+    return None
+
+if __name__ == '__main__':
+    try:
+        c = get_config()
+        verify(c)
+        generate(c)
+        apply(c)
+    except ConfigError as e:
+        print(e)
+        exit(1)