Apply ConfigEntryNotReady improvements to PlatformNotReady (#48665)

* Apply ConfigEntryNotReady improvements to PlatformNotReady

- Limit log spam #47201
- Log exception reason #48449
- Prevent startup blockage #48660

* coverage

homeassistant/helpers/entity_platform.py

@@ -9,9 +9,14 @@ from types import ModuleType
 from typing import TYPE_CHECKING, Callable, Coroutine, Iterable
 
 from homeassistant import config_entries
-from homeassistant.const import ATTR_RESTORED, DEVICE_DEFAULT_NAME
+from homeassistant.const import (
+    ATTR_RESTORED,
+    DEVICE_DEFAULT_NAME,
+    EVENT_HOMEASSISTANT_STARTED,
+)
 from homeassistant.core import (
     CALLBACK_TYPE,
+    CoreState,
     HomeAssistant,
     ServiceCall,
     callback,
@@ -215,23 +220,41 @@ class EntityPlatform:
             hass.config.components.add(full_name)
             self._setup_complete = True
             return True
-        except PlatformNotReady:
+        except PlatformNotReady as ex:
             tries += 1
             wait_time = min(tries, 6) * PLATFORM_NOT_READY_BASE_WAIT_TIME
+            message = str(ex)
+            if not message and ex.__cause__:
+                message = str(ex.__cause__)
+            ready_message = f"ready yet: {message}" if message else "ready yet"
+            if tries == 1:
                 logger.warning(
-                "Platform %s not ready yet. Retrying in %d seconds.",
+                    "Platform %s not %s; Retrying in background in %d seconds",
                     self.platform_name,
+                    ready_message,
+                    wait_time,
+                )
+            else:
+                logger.debug(
+                    "Platform %s not %s; Retrying in %d seconds",
+                    self.platform_name,
+                    ready_message,
                     wait_time,
                 )
 
-            async def setup_again(now):  # type: ignore[no-untyped-def]
+            async def setup_again(*_):  # type: ignore[no-untyped-def]
                 """Run setup again."""
                 self._async_cancel_retry_setup = None
                 await self._async_setup_platform(async_create_setup_task, tries)
 
+            if hass.state == CoreState.running:
                 self._async_cancel_retry_setup = async_call_later(
                     hass, wait_time, setup_again
                 )
+            else:
+                self._async_cancel_retry_setup = hass.bus.async_listen_once(
+                    EVENT_HOMEASSISTANT_STARTED, setup_again
+                )
             return False
         except asyncio.TimeoutError:
             logger.error(

tests/helpers/test_entity_platform.py

@@ -6,8 +6,8 @@ from unittest.mock import Mock, patch
 
 import pytest
 
-from homeassistant.const import PERCENTAGE
+from homeassistant.const import EVENT_HOMEASSISTANT_STARTED, PERCENTAGE
-from homeassistant.core import callback
+from homeassistant.core import CoreState, callback
 from homeassistant.exceptions import HomeAssistantError, PlatformNotReady
 from homeassistant.helpers import (
     device_registry as dr,
@@ -592,6 +592,52 @@ async def test_setup_entry_platform_not_ready(hass, caplog):
     assert len(mock_call_later.mock_calls) == 1
 
 
+async def test_setup_entry_platform_not_ready_with_message(hass, caplog):
+    """Test when an entry is not ready yet that includes a message."""
+    async_setup_entry = Mock(side_effect=PlatformNotReady("lp0 on fire"))
+    platform = MockPlatform(async_setup_entry=async_setup_entry)
+    config_entry = MockConfigEntry()
+    ent_platform = MockEntityPlatform(
+        hass, platform_name=config_entry.domain, platform=platform
+    )
+
+    with patch.object(entity_platform, "async_call_later") as mock_call_later:
+        assert not await ent_platform.async_setup_entry(config_entry)
+
+    full_name = f"{ent_platform.domain}.{config_entry.domain}"
+    assert full_name not in hass.config.components
+    assert len(async_setup_entry.mock_calls) == 1
+
+    assert "Platform test not ready yet" in caplog.text
+    assert "lp0 on fire" in caplog.text
+    assert len(mock_call_later.mock_calls) == 1
+
+
+async def test_setup_entry_platform_not_ready_from_exception(hass, caplog):
+    """Test when an entry is not ready yet that includes the causing exception string."""
+    original_exception = HomeAssistantError("The device dropped the connection")
+    platform_exception = PlatformNotReady()
+    platform_exception.__cause__ = original_exception
+
+    async_setup_entry = Mock(side_effect=platform_exception)
+    platform = MockPlatform(async_setup_entry=async_setup_entry)
+    config_entry = MockConfigEntry()
+    ent_platform = MockEntityPlatform(
+        hass, platform_name=config_entry.domain, platform=platform
+    )
+
+    with patch.object(entity_platform, "async_call_later") as mock_call_later:
+        assert not await ent_platform.async_setup_entry(config_entry)
+
+    full_name = f"{ent_platform.domain}.{config_entry.domain}"
+    assert full_name not in hass.config.components
+    assert len(async_setup_entry.mock_calls) == 1
+
+    assert "Platform test not ready yet" in caplog.text
+    assert "The device dropped the connection" in caplog.text
+    assert len(mock_call_later.mock_calls) == 1
+
+
 async def test_reset_cancels_retry_setup(hass):
     """Test that resetting a platform will cancel scheduled a setup retry."""
     async_setup_entry = Mock(side_effect=PlatformNotReady)
@@ -614,6 +660,31 @@ async def test_reset_cancels_retry_setup(hass):
     assert ent_platform._async_cancel_retry_setup is None
 
 
+async def test_reset_cancels_retry_setup_when_not_started(hass):
+    """Test that resetting a platform will cancel scheduled a setup retry when not yet started."""
+    hass.state = CoreState.starting
+    async_setup_entry = Mock(side_effect=PlatformNotReady)
+    initial_listeners = hass.bus.async_listeners()[EVENT_HOMEASSISTANT_STARTED]
+
+    platform = MockPlatform(async_setup_entry=async_setup_entry)
+    config_entry = MockConfigEntry()
+    ent_platform = MockEntityPlatform(
+        hass, platform_name=config_entry.domain, platform=platform
+    )
+
+    assert not await ent_platform.async_setup_entry(config_entry)
+    await hass.async_block_till_done()
+    assert (
+        hass.bus.async_listeners()[EVENT_HOMEASSISTANT_STARTED] == initial_listeners + 1
+    )
+    assert ent_platform._async_cancel_retry_setup is not None
+
+    await ent_platform.async_reset()
+    await hass.async_block_till_done()
+    assert hass.bus.async_listeners()[EVENT_HOMEASSISTANT_STARTED] == initial_listeners
+    assert ent_platform._async_cancel_retry_setup is None
+
+
 async def test_not_fails_with_adding_empty_entities_(hass):
     """Test for not fails on empty entities list."""
     component = EntityComponent(_LOGGER, DOMAIN, hass)