letsdns package¶

Submodules¶

letsdns.action module¶

class letsdns.action.Action¶

Bases: ABC

Abstract base class for LetsDNS actions.

abstract execute(conf: Config, *args, **kwargs) → int¶

Action classes MUST implement this method. Unknown positional and keyword arguments MUST be ignored.

Args:: conf: Configuration data. args: Positional arguments. kwargs: Keyword arguments.

classmethod lifecycle(conf: Config, action) → int¶

Invoke the lifecycle methods of a dynamically imported action. The first non-zero method return code will abort execution and will be returned to the caller.

Args:: conf: Configuration data. action: Action object. Ignored in the default implementation.

setup(conf: Config) → int¶: Pre-execution phase, for initialisation.

teardown(conf: Config) → int¶: Post-execution phase, for cleanup.

letsdns.action.import_action(class_name: str) → Type[Action]¶

Dynamically import an action class. Raises a TypeError exception if the imported class is not a subclass of ‘Action’.

Args:: class_name: Fully qualified class name, e.g. “mymodule.actions.SomeAction”.

letsdns.action.import_class(class_name: str)¶

Dynamically import a Python class. The containing module must be available in PYTHONPATH.

Args:: class_name: Fully qualified class name, e.g. “mymodule.submodule.MyClass”.

letsdns.configuration module¶

class letsdns.configuration.Config¶

Bases: object

Provide access to configuration data.

dump(destination=<_io.TextIOWrapper name='<stdout>' mode='w' encoding='utf-8'>) → None¶

Dump configuration state into a file.

Args:: destination: File pointer.

get(name: str, fallback=None) → str¶

Return an optional configuration value or the specified fallback value.

Args:: name: Option name. fallback: Returned if option is undefined.

get_domain() → str¶

Return the mandatory ‘domain’ configuration value.

Raise an exception if ‘domain’ is undefined.

get_mandatory(name: str) → str¶

Return a mandatory configuration value. Raise an exception if option value is undefined.

Args:: name: Option name.

get_tcp_ports() → List[str]¶: Return the optional ‘tcp_ports’ configuration value.

get_ttl() → int¶: Return the ‘ttl’ configuration value (seconds, integer).

init(filenames=None) → None¶

Initialise object by loading configuration files from disk. Nonexisting or unreadable files are silently ignored.

Args:: filenames: Either a single string or a list of strings.

options() → List[str]¶: Return all options in the active section.

letsdns.configuration.init_logger() → None¶: Initialise logger.

letsdns.configuration.log_level(default: str = 'ERROR') → int¶

Return logging level, using the LOG_LEVEL environment variable if available.

Args:: default: The default log level.

letsdns.core module¶

letsdns.core.action_class(name: str) → Action | None¶

Return action class for the given name.

Args:: name: Action name.

letsdns.core.traverse_config(conf: Config) → int¶

Traverse and process the configuration sections. Return the number of processed actions.

Args:: conf: Configuration object.

letsdns.crypto module¶

letsdns.crypto.dane_tlsa_records(cert: Certificate) → List[str]¶

Return list of TLSA record data for the certificate.

Args:: cert: x509 certificate.

letsdns.crypto.read_x509_cert(filename: str) → Certificate¶: Read x509 certificate from file.

letsdns.crypto.sha_digests(something)¶: Generate hexadecimal SHA256 and SHA512 hashes for some data.

letsdns.hetznerapi module¶

class letsdns.hetznerapi.HetznerApiUpdate¶

Bases: Action

cleanup_records(zone_id: str, name: str) → bool¶

Delete existing TLSA records. Returns True to indicate success.

Args:: zone_id: Parent zone ID. name: DNS record name.

execute(conf: Config, *args, **kwargs) → int¶: Update DNS record using the Hetzner DNS API. Return 0 to indicate success.

find_records(zone_id: str, name: str) → List[str] | None¶

Returns matching record ID list for the given zone ID and name, or None in case of errors.

Args:: zone_id: Parent zone ID. name: DNS record name.

classmethod lifecycle(conf: Config, action: Action) → int¶: Process configuration data.

zone_id(domain: str) → str | None¶

Returns zone ID for the given domain name, or None in case of errors.

Args:: domain: Domain name, e.g. “example.com”.

letsdns.liveupdate module¶

class letsdns.liveupdate.DnsLiveUpdate¶

Bases: Action

execute(conf: Config, *args, **kwargs) → int¶: Update DNS record using the dnspython library. Return 0 to indicate success.

classmethod lifecycle(conf: Config, action: Action) → int¶

Invoke the lifecycle methods of a dynamically imported action. The first non-zero method return code will abort execution and will be returned to the caller.

Args:: conf: Configuration data. action: Action object. Ignored in the default implementation.

letsdns.nsupdate module¶

class letsdns.nsupdate.NsupdateStdout¶

Bases: Action

execute(conf: Config, *args, **kwargs) → int¶: Generate ‘nsupdate’ command list and print to stdout.

classmethod lifecycle(conf: Config, action) → int¶

Invoke the lifecycle methods of a dynamically imported action. The first non-zero method return code will abort execution and will be returned to the caller.

Args:: conf: Configuration data. action: Action object. Ignored in the default implementation.

letsdns.tlsa module¶

letsdns.tlsa.rdata_action_lifecycle(conf: Config, action: Action) → int¶: Lifecycle method for Rdata-based actions.

letsdns.tlsa.record_name(conf: Config, tcp_port: str) → str¶

Return TLSA record name for the configured host name. A single dot ‘.’ host name denotes the domain apex.

Args:: conf: Configuration object. tcp_port: Desired TCP service port, default 25.

letsdns.tlsa.tlsa_records(conf: Config) → List[str]¶

Generate list of TLSA record strings based on the given configuration options.

Args:: conf: Configuration object.

letsdns.util module¶

letsdns.util.getenv(name: str, default=None, debug_env=True)¶

Return environment variable value if available, otherwise return the default value.

Args:: name: Environment variable name. default: Default value. debug_env: Debug variable name/value.

letsdns.util.is_sensitive(name: str) → bool¶: Return True if the specified name is considered sensitive.

letsdns.util.is_truthy(something) → bool¶

Test if ‘something’ represents boolean True.

An object represents True if it is (or can be converted to) a string and said string’s first character, converted to lowercase, is one of: 1, t, y.

Args:: something: The object to examine.

letsdns.util.split(source: str) → List[str]¶

Split a string where whitespace or comma occurs. Return empty list for invalid input.

Args:: source: The string to be split.

Module contents¶

This file is part of LetsDNS.

LetsDNS is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

LetsDNS 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 LetsDNS. If not, see <https://www.gnu.org/licenses/>.