From 633ff0ea42a327f38e54959c972bcf148dc4062c Mon Sep 17 00:00:00 2001
From: Matthias Alphart <farmio@alphart.net>
Date: Wed, 28 Aug 2024 13:14:34 +0200
Subject: [PATCH] Handle KNX expose conversion exceptions and unavailable
 states (#124776)

---
 homeassistant/components/knx/expose.py | 24 +++++++++++++++------
 tests/components/knx/test_expose.py    | 29 ++++++++++++++++++++++----
 2 files changed, 43 insertions(+), 10 deletions(-)

diff --git a/homeassistant/components/knx/expose.py b/homeassistant/components/knx/expose.py
index 921af6ba4a9..82bee48ba69 100644
--- a/homeassistant/components/knx/expose.py
+++ b/homeassistant/components/knx/expose.py
@@ -125,6 +125,8 @@ class KNXExposeSensor:
     def _get_expose_value(self, state: State | None) -> bool | int | float | str | None:
         """Extract value from state."""
         if state is None or state.state in (STATE_UNKNOWN, STATE_UNAVAILABLE):
+            if self.expose_default is None:
+                return None
             value = self.expose_default
         elif self.expose_attribute is not None:
             _attr = state.attributes.get(self.expose_attribute)
@@ -154,12 +156,22 @@ class KNXExposeSensor:
         if value is not None and (
             isinstance(self.device.sensor_value, RemoteValueSensor)
         ):
-            if issubclass(self.device.sensor_value.dpt_class, DPTNumeric):
-                return float(value)
-            if issubclass(self.device.sensor_value.dpt_class, DPTString):
-                # DPT 16.000 only allows up to 14 Bytes
-                return str(value)[:14]
-        return value
+            try:
+                if issubclass(self.device.sensor_value.dpt_class, DPTNumeric):
+                    return float(value)
+                if issubclass(self.device.sensor_value.dpt_class, DPTString):
+                    # DPT 16.000 only allows up to 14 Bytes
+                    return str(value)[:14]
+            except (ValueError, TypeError) as err:
+                _LOGGER.warning(
+                    'Could not expose %s %s value "%s" to KNX: Conversion failed: %s',
+                    self.entity_id,
+                    self.expose_attribute or "state",
+                    value,
+                    err,
+                )
+                return None
+        return value  # type: ignore[no-any-return]
 
     async def _async_entity_changed(self, event: Event[EventStateChangedData]) -> None:
         """Handle entity change."""
diff --git a/tests/components/knx/test_expose.py b/tests/components/knx/test_expose.py
index c4d0acf0ce2..0fd790a3e33 100644
--- a/tests/components/knx/test_expose.py
+++ b/tests/components/knx/test_expose.py
@@ -108,6 +108,11 @@ async def test_expose_attribute(hass: HomeAssistant, knx: KNXTestKit) -> None:
     await hass.async_block_till_done()
     await knx.assert_telegram_count(0)
 
+    # Ignore "unavailable" state
+    hass.states.async_set(entity_id, "unavailable", {attribute: None})
+    await hass.async_block_till_done()
+    await knx.assert_telegram_count(0)
+
 
 async def test_expose_attribute_with_default(
     hass: HomeAssistant, knx: KNXTestKit
@@ -131,7 +136,7 @@ async def test_expose_attribute_with_default(
     await knx.receive_read("1/1/8")
     await knx.assert_response("1/1/8", (0,))
 
-    # Change state to "on"; no attribute
+    # Change state to "on"; no attribute -> default
     hass.states.async_set(entity_id, "on", {})
     await hass.async_block_till_done()
     await knx.assert_write("1/1/8", (0,))
@@ -146,6 +151,11 @@ async def test_expose_attribute_with_default(
     await hass.async_block_till_done()
     await knx.assert_no_telegram()
 
+    # Use default for "unavailable" state
+    hass.states.async_set(entity_id, "unavailable")
+    await hass.async_block_till_done()
+    await knx.assert_write("1/1/8", (0,))
+
     # Change state and attribute
     hass.states.async_set(entity_id, "on", {attribute: 3})
     await hass.async_block_till_done()
@@ -290,8 +300,18 @@ async def test_expose_value_template(
     assert "Error rendering value template for KNX expose" in caplog.text
 
 
+@pytest.mark.parametrize(
+    "invalid_attribute",
+    [
+        101.0,
+        "invalid",  # can't cast to float
+    ],
+)
 async def test_expose_conversion_exception(
-    hass: HomeAssistant, caplog: pytest.LogCaptureFixture, knx: KNXTestKit
+    hass: HomeAssistant,
+    caplog: pytest.LogCaptureFixture,
+    knx: KNXTestKit,
+    invalid_attribute: str,
 ) -> None:
     """Test expose throws exception."""
 
@@ -313,16 +333,17 @@ async def test_expose_conversion_exception(
     await knx.receive_read("1/1/8")
     await knx.assert_response("1/1/8", (3,))
 
+    caplog.clear()
     # Change attribute: Expect no exception
     hass.states.async_set(
         entity_id,
         "on",
-        {attribute: 101},
+        {attribute: invalid_attribute},
     )
     await hass.async_block_till_done()
     await knx.assert_no_telegram()
     assert (
-        'Could not expose fake.entity fake_attribute value "101.0" to KNX:'
+        f'Could not expose fake.entity fake_attribute value "{invalid_attribute}" to KNX:'
         in caplog.text
     )