Initial commit.

main.py

@@ -0,0 +1,157 @@
+#!/usr/bin/env python3
+
+import itertools
+import json
+import os
+import sys
+import logging
+
+import yaml
+import schema
+import click
+import ovh
+import dns.resolver
+import dns.rdatatype
+
+from schema import And, Optional, Use, Schema
+
+logger = logging.getLogger('ovhdns')
+
+config_schema = Schema({
+    'ovh': {
+        'application_key': Use(str),
+        'application_secret': Use(str),
+        'consumer_key': Use(str),
+        'endpoint': Use(str),
+    },
+    'zone': Use(str),
+    'subdomain': Use(str),
+    Optional('field_type', default='A'): And(Use(str), Use(str.upper), dns.rdatatype.RdataType.make),
+    Optional('logging', default={'level': ':WARNING,ovhdns:INFO'}): {
+        Optional('level', default=':WARNING,ovhdns:INFO'): Use(str),
+    },
+    Optional('ttl', default=None): Use(lambda i: int(i) if i is not None else None),
+})
+
+def get_opendns_ips():
+    ips = []
+    for addr, typ in itertools.product(
+        ['resolver1.opendns.com', 'resolver2.opendns.com'],
+        ['A', 'AAAA'],
+    ):
+        ips += [r.to_text() for r in dns.resolver.resolve(addr, typ)]
+    return ips
+
+def get_my_ips():
+    resolver = dns.resolver.Resolver(configure=False)
+    resolver.nameservers = get_opendns_ips()
+    return [r.to_text() for r in resolver.resolve('myip.opendns.com')]
+
+
+def get_records(client, config):
+    zone = config['zone']
+    records = client.get(f'/domain/zone/{zone}/record')
+    records = [
+        client.get(f'/domain/zone/{zone}/record/{id}')
+        for id in records
+    ]
+    return records
+
+def init_logging():
+    logging.getLogger().addHandler(
+        logging.StreamHandler(),
+    )
+
+def set_logging_level(level: str):
+    levels = {
+        'NOTSET': logging.NOTSET,
+        'DEBUG': logging.DEBUG,
+        'INFO': logging.INFO,
+        'WARNING': logging.WARNING,
+        'WARN': logging.WARNING,
+        'ERROR': logging.ERROR,
+        'CRITICAL': logging.CRITICAL,
+    }
+
+    log_levels = [x.split(':') for x in level.split(',')]
+    for module, level in log_levels:
+        module = module.strip() if module else None
+        level = level.strip().upper()
+        if level not in levels:
+            raise ValueError(f'invalid log level, allowed values: {repr(set(levels.keys()))}')
+        logging.getLogger(module).setLevel(levels[level])
+
+def load_config(file):
+    if file == '-':
+        config = yaml.safe_load(sys.stdin)
+    else:
+        if os.stat(file).st_mode & 0o777 & ~0o600:
+            raise Exception('refusing to load insecure configuration file, file must have permission 0o600')
+        with open(file) as fp:
+            config = yaml.safe_load(fp)
+    return config_schema.validate(config)
+
+@click.command()
+@click.option('--config', '-c', envvar='OVHDNS_CONFIG', default='-', help='The configuration file')
+@click.option('--level', '-l', envvar='OVHDNS_LEVEL', default=None, help='The log level for the application')
+@click.option('--force-refresh', '-f', envvar='OVHDNS_FORCE_REFRESH', is_flag=True, help='Force zone refresh even if deemed not needed')
+def main(config, level, force_refresh):
+    init_logging()
+    config = load_config(config)
+    if level:
+        config['logging']['level'] = level
+    config = config_schema.validate(config)
+    set_logging_level(config['logging']['level'])
+
+    ovh_client = ovh.Client(
+        **config['ovh'],
+    )
+    records = [
+        r
+        for r in get_records(ovh_client, {'zone': 'redxef.at'})
+        if r['fieldType'] == config['field_type']
+        and r['zone'] == config['zone']
+        and r['subDomain'] == config['subdomain']
+    ]
+    logger.info('found matching records: %s', records)
+    if len(records) > 1:
+        logger.error('found more than one record, don\'t know which to pick')
+        sys.exit(1)
+
+    my_ips = get_my_ips()
+    need_refresh = False
+    if len(records) == 1:
+        logger.info('record already present, updating if needed')
+        if my_ips[0] == records[0]['target']:
+            logger.info('ip is up-to-date, skipping update')
+        else:
+            need_refresh = True
+            ovh_client.put(
+                f'/domain/zone/{config["zone"]}/record/{records[0]["id"]}',
+                target=my_ips[0],
+                ttl=config['ttl'],
+            )
+            logger.info('updated record, new ip is %s', my_ips[0])
+
+    else:
+        logger.info('record not already present, creating new one')
+        need_refresh = True
+        ovh_client.post(
+            f'/domain/zone/{config["zone"]}/record/',
+            subDomain=config['subdomain'],
+            target=my_ips[0],
+            fieldType=config['field_type'],
+            ttl=config['ttl'],
+        )
+        logger.info('created new record, ip is %s', my_ips[0])
+
+    if need_refresh or force_refresh:
+        ovh_client.post(f'/domain/zone/{config["zone"]}/refresh')
+        logger.info('refreshed zone')
+    else:
+        logger.info('zone refresh skipped')
+    sys.exit(0)
+
+if __name__ == '__main__':
+    main()
+

requirements.txt

@@ -0,0 +1,5 @@
+pyyaml
+schema
+click
+ovh
+dnspython