Changelog

Version 2.2.0

The client connection handling has been substantially rewritten. This should eliminate some race conditions, but may also cause changes in behaviour in corner cases, such as the exact circumstances in which callbacks are made and the order in which they occur.

• Change Client.wait_connected() so that it will raise an exception if the client is closed (with Client.close()), rather than blocking forever.

• Improve handling of back-pressure in DeviceServer. Previously, once max_pending requests were active, each connection would continue reading the next request and only block when trying to start it. Now, when max_pending is reached, all connections immediately stop reading.

• Stop debug logging incoming informs twice.

• Add a Developer Manual to the documentation.

• Fix a race condition in SensorWatcher that could cause an infinite loop.

• Speed up decoding of bytes arguments.

Version 2.1.0

• Add AbstractSensorWatcher.filter() to allow only a subset of sensors to be watched.

• Fix calculation of the randomised exponent backoff for connection attempts.

• Update CI to use Ubuntu 24.04.

Version 2.0.2

• Support async-timeout 5.0 (and remove support for pre-1.3 versions).

Version 2.0.1

• Disconnect a client if it is not able to keep up with #sensor-status informs. Previously this was only checked when broadcasting an inform to all clients, such as #interface-changed.

• Avoid disconnecting a client with a large backlog during handling of ?sensor-sampling requests, as this can trigger a large burst of #sensor-status informs.

• Fix unit tests for Python 3.13.

Version 2.0.0

Breaking changes:

• When setting the value of a sensor, it is coerced to an instance of the sensor type (see Sensor value coercion). Reading back the sensor value will give this coerced object instead of the original. This only applies if the value was not already of the expected type.

• Setting a sensor value to an object of an unsupported type will now raise TypeError. Previously it was silently accepted, and clients querying the sensor would either get a value of the wrong type, or the query would fail.

• The Address constructor now raises TypeError if the first argument is not an IP address object.

Other changes:

• Use typing.get_args() instead of an undocumented API.

Version 1.10.0

• Use katcp-codec to provide the low-level encoding and decoding of katcp messages, yielding a significant speedup.

Version 1.10.0b1

• Use katcp-codec to provide the low-level encoding and decoding of katcp messages, yielding a significant speedup.

Version 1.9.0

• Drop support for end-of-life Python 3.7.

• Significantly speed up argument decoding for request handlers. Note that any code that calls register_type() will need to be updated.

• Add Client.sensor_reading() and Client.sensor_value() helper methods.

• Update dependency versions in Github Actions.

Version 1.8.0

• Make Reading a dataclass.

• Fix server shutdown on Python 3.12.

• Update versions of dependencies used in CI.

• Remove wheel from build-system.requires.

• Make the unit tests pass on Python 3.11.5.

• Make the adjtimex module available on non-Linux systems with a stub implementation. It raises NotImplementedError when calling get_adjtimex(), and TimeSyncUpdater will set the sensors to INACTIVE.

Version 1.7.0

• Extend SensorWatcher to allow incoming sensors to be replicated under multiple names.

• Log exception traceback when a service task crashes.

Version 1.6.2

• Make things work on MacOS again.

• CI: Update certifi to a newer version.

• Add a type annotation to prevent an internal error in old versions of mypy.

Version 1.6.1

• Workaround to prevent old versions of mypy (0.780) from throwing an internal error.

Version 1.6.0

• Add DeviceStatus enum for discrete device-status sensors.

• Add TimeSyncUpdater to assist in writing sensors that monitor time synchronisation.

Version 1.5.1

• Make PEP 604 union syntax work in handler annotations.

• Speed up message parsing, particularly for messages with thousands of arguments.

Version 1.5.0

• Add SimpleAggregateSensor class to simplify common use cases for aggregate sensors.

• Improve error reporting when requests are made with too few arguments, particularly when the handler is wrapped in a decorator.

• Allow handler arguments to be annotated as Optional[T]. It’s not possible to provide a None value on the wire, but this allows the default value to be None while complying with mypy’s strict mode.

• Update katcpcmd and the examples to use asyncio.run() instead of manually running the event loop. This eliminates some deprecation warnings.

• Update pre-commit hook to point to flake8’s new Github URL.

• Test on Python 3.11.

Version 1.4.0

• Replace None with '' for a default sensor description. If no description is given, the ?sensor-list request would fail. This is now fixed.

• Add AggregateSensor functionality, an abstract class of sensors which depend on the readings of others for their values.

Version 1.3.1

• Fix a resource leak that prevented full cleanup of client state on the server after the client disconnected (although the garbage collector would have cleaned it up eventually).

Version 1.3.0

• Use bulk sensor sampling in SensorWatcher when available.

Version 1.2.0

• Add support for Service tasks.

Version 1.1.0

• Increment server protocol version to 5.1.

• Implement bulk sensor sampling feature of katcp 5.1.

• Bump minimum Python version to 3.7, and run test suite against 3.10.

• Change type annotation of Server.server from asyncio.AbstractServer to the more specific asyncio.Server.

• Add Server.sockets to simplify querying the sockets of a server.

• Lots of internal code modernisation (f-strings, PEP 526 type annotations, isort, and so on).

Version 1.0.0

• Drop support for Python 3.5, and test on versions up to 3.9.

• Remove explicit loop arguments.

• Fix a race condition that could cause lost connections to be logged twice.

• Switch testing from nosetests to pytest.

• Switch CI from Travis CI to Github Actions.

• Use a pyproject.toml to specify build-time dependencies.

• Upgrade Sphinx used for readthedocs to the latest version.

Version 0.8.0

• Add SensorSet.add_add_callback(), SensorSet.remove_add_callback() and SensorSet.remove_remove_callback().

Version 0.7.0

• Add auto_strategy parameter to Sensor constructor.

• Disconnect clients that aren’t keeping up with their asynchronous informs.

Version 0.6.1

• Fix the type annotations to allow Client.add_sensor_watcher() to take a AbstractSensorWatcher instead of a SensorWatcher.

• Always call sensor watchers in the order they were added.

Version 0.6.0

• Add Server.on_stop().

Version 0.5.0

• Make SensorSet more generic and move into aiokatcp.sensor package. It no longer takes a list of connections; instead, one may register callbacks to get notification of removals. Note that the constructor interface has changed in a non-compatible way.

• Add Sensor.Status.valid_value().

• Add Client.add_inform_callback() and Client.remove_inform_callback().

• Add support for Watching sensors.

Version 0.4.4

• Support Python 3.7

Version 0.4.3

• Fix endless loop of “socket.send() raised except” when client disconnects

Version 0.4.2

• Make Client work with servers that don’t support message IDs

Version 0.4.1

• Make async-timeout a requirement so that katcpcmd works

• Make SensorSet a subclass of Mapping for better type checking

Version 0.4.0

• Change type system to support abstract types

• Suppress logged exception when client connection is reset

Version 0.3.2

• Fixes some annotations to work with the latest mypy; no functional changes

Version 0.3.1

• Add peer addresses to various log messages

Version 0.3

• Add status_func parameter to Sensor constructor.

Version 0.2

• Add client support

• Correctly handle carriage returns (\r)

• Bound the number of in-flight requests

• Change the exact error message when a sensor does not exist, for better compatibility with katcp.inspecting_client.

Version 0.1

• First release