Changelog

2.2.1 (2026-06-16)

add strict static typing with basedpyright across modpoll/; introduce modpoll/types.py and enforce make typecheck in local and CI quality gates
extract Device, Poller, and Reference into modpoll/modbus_models.py (orchestration remains in modbus_task.py)
replace black with ruff for format and lint

MQTT on-demand read (get): subscribe on modpoll/+/get (--mqtt-get-topic-pattern); publish {"ref": null} to modpoll/{device}/get; response on modpoll/{device}/get/response with partial success (unknown or failed refs omitted); targeted Modbus reads via reference_read.py with adjacent register batching
Persistent Modbus connection: ModbusConnectionManager keeps the client open between poll cycles and MQTT commands; non-blocking exponential reconnect backoff (--modbus-backoff-base, --modbus-backoff-max); optional connection recycle (--modbus-max-connection-age)
enrich per-device MQTT diagnostics with config_source, get/set counters (get_count, get_errors, get_success, get_unknown_refs, get_read_errors, set_count, set_errors, set_success, set_unknown_refs)
publish process-wide health on modpoll/diagnostics (mqtt_connected, modbus_ok, devices_failing, last_cycle_s, Modbus connection state and reconnect metrics)
publish process presence on modpoll/status with last-will (online: false) and birth message (online: true); status is always retained
apply --mqtt-retain to diagnostics topics (same policy as data publishes)

``–interval`` default is now transport-aware: 0.0 s for TCP/UDP (was 0.5 s); serial/RTU derives the RTU 3.5-character frame gap from --serial-baud with a 0.005 s floor. Set --interval explicitly for slow devices.
Modbus connect/close per poll cycle removed: the client stays open until shutdown or a transport failure; on serial/RTU the port remains reserved while modpoll runs
MQTT multi-reference writes now use --interval between successive refs in one set message (was a fixed 0.1 s delay)

document MQTT get, persistent connection, transport-aware --interval, and extended diagnostics in docs/usage.rst

add tests/test_modbus_connection.py, extend tests/test_main_get.py for backoff, connection reuse, and diagnostic counters
migrate Modbus lifecycle tests to ModbusConnectionManager

warn at config load when a reference is marked w/rw on a discrete_input or input_register poller (Modbus inputs are read-only)

fix README MQTT write example for bool8 references (array of 8 booleans, not a scalar)
document export, diagnostics, mqtt-single, config sources, write constraints, and publish behavior in docs/usage.rst
expand docs/configure.rst with CSV schema, dtypes, poll limits, and validation rules
correct config_template.csv comment: dtype column is required

add contract tests in tests/test_handler_behavior.py for documented edge cases
consolidate handler regression/contract tests; share FakeModbusMaster in tests/helpers/modbus.py

add --mqtt-retain to set the MQTT retain flag on data publishes (diagnostics topics are never retained)

add release documentation checklist for agents and maintainers in CONTRIBUTING.md
align narrative docs with MQTT reference-map write format and --mqtt-keys usage

centralize MQTT data publish policy (QoS and retain) in MqttHandler.publish_data_message

add --mqtt-keys name-only to publish MQTT JSON keys without the unit suffix (default key style remains name-with-unit)
MQTT writes on modpoll/{device}/set accept a map of references {"ref_a": val, "ref_b": val} in one message; unknown keys are skipped with a warning

renamed --daemon / -d to --no-output (suppresses poll result tables only; does not fork)
MQTT write payload must be a reference map ({"ref": val}); ref/value object format removed

forked from modpoll; PyPI package renamed to modpoll2mqtt, repository yoch/modpoll2mqtt
CLI command and Python module remain modpoll

semantic MQTT write by CSV reference on modpoll/{device}/set with payload ref and value (device from topic; scale, dtype, and endianness handled automatically)
subscribe pattern modpoll/+/set by default

removed low-level MQTT write format (object_type, address, value); use topic + ref and value instead
duplicate reference names on the same device now abort config loading (previously warned and overwrote)