Maintenance: dependency updates and bug fixes

[eman]

Summary

Routine maintenance pass covering two dependency updates, a broken test collection issue, and five logic bugs found during a code review.

---

Dependency & Test Infrastructure

awsiotsdk minimum version bumped to 1.28.2

The previously declared minimum (>=1.27.0) was behind the current patch release. Bumped to >=1.28.2, which also pulls in awscrt 0.31.3 transitively.

Hypothesis test no longer breaks test collection

tests/test_mqtt_hypothesis.py imported hypothesis at module level. When hypothesis was not installed, pytest failed to collect all tests — not just that file. Replaced the bare import with pytest.importorskip("hypothesis") so the tests skip gracefully instead.

---

Bug Fixes

Anti-Legionella set-period always enabled the feature (cli/handlers.py)

Both if/else branches of the enabled-state check called enable_anti_legionella(). A device with anti-legionella disabled would be silently re-enabled when the user ran nwp-cli anti-legionella set-period. The else branch now calls disable_anti_legionella() to preserve the current state.

Subscriptions permanently lost after failed resubscription (mqtt/subscriptions.py)

resubscribe_all() cleared _subscriptions and _message_handlers before the re-subscribe loop. Any topic that failed to resubscribe was dropped from internal state entirely and could never be retried on the next reconnection. Failed topics are now restored to internal state so they are retried on the next reconnect.

_detect_unit_system() returned None on timeout (cli/main.py)

The function declared return type UnitSystemType but returned None on TimeoutError. Now returns "us_customary" to match the warning message and the type contract.

Once-listener could become permanent with duplicate callbacks (events.py)

emit() identified once-listeners via a set of (event, callback) tuples. If the same callback was registered twice with once=True, the set deduplicated the tuple — after the first emit, the second listener lost its once-status and became permanent. Fixed by checking listener.once directly on the EventListener object instead.

Auth session leaked if client construction raised (factory.py)

In create_navien_clients(), the NavienAPIClient and NavienMqttClient constructors were called after auth_client.aenter() but outside its cleanup guard. If either constructor raised, the auth session and its underlying aiohttp session would leak. Client construction is now wrapped in its own try/except that calls auth_client.aexit() on failure.

---

Test Results

• 446 passed, 4 skipped
• Linting: all checks passed
• Type checking: 0 errors

[Copilot]

Pull request overview

Routine maintenance updates across the dependency surface, test collection behavior, and several runtime correctness fixes in the CLI, MQTT subscription manager, event emitter, and client factory.

Changes:

• Bump awsiotsdk minimum version and ensure Hypothesis-based tests skip cleanly when Hypothesis isn’t installed.
• Fix multiple logic issues (anti-legionella CLI state handling, subscription resubscribe state restoration, unit-system timeout return value, once-listener handling).
• Prevent auth-session leakage when client construction fails after auth context entry.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tests/test_mqtt_hypothesis.py	Avoids pytest collection failure by skipping the file when Hypothesis is missing.
src/nwp500/mqtt/subscriptions.py	Restores failed topics/handlers into internal state so resubscribe can be retried on next reconnect.
src/nwp500/factory.py	Ensures auth context is exited if API/MQTT client construction raises after successful __aenter__().
src/nwp500/events.py	Fixes once-listener semantics by using the listener’s once flag instead of a deduplicating set lookup.
src/nwp500/cli/handlers.py	Adjusts anti-legionella set-period logic to avoid always enabling the feature (but see review comment).
src/nwp500/cli/__main__.py	Returns a concrete UnitSystemType on timeout instead of None.
setup.cfg	Updates minimum awsiotsdk requirement to >=1.28.2.

---

You can also share your feedback on Copilot code review. Take the survey.