Blog post and docs update Exception translations (#2113)

Co-authored-by: Martin Hjelmare <marhje52@gmail.com>

blog/2023-11-30-service-exceptions-and-translations.md

@@ -19,7 +19,7 @@ Integrations should be updated and raise `ServiceValidationError` instead of `Va
 
 ## Translation support for Exceptions
 
-The `HomeAssistantError` exception and its subclasses, including `ServiceValidationError`, now accept a translation key to allow localization. [Read more](/docs/internationalization/core/#exceptions). The translation key will be used in cases where the frontend receives information about the exception.
+The `HomeAssistantError` exception and its subclasses, including `ServiceValidationError`, now accept a translation key to allow localization. [Read more](/docs/internationalization/core/#exceptions). The translation key will be used in cases where the frontend receives information about the exception. The English error message from the translation cache will also be used to log a message to the console if no custom error message is passed to the exception as argument.
 
 ### Background
 

blog/2024-03-15-exception-translations.md

@@ -0,0 +1,43 @@
+---
+author: Jan Bouwhuis
+authorURL: https://github.com/jbouwh
+authorImageURL: https://avatars.githubusercontent.com/u/7188918?s=96&v=4
+title: Raising exceptions with translations
+---
+
+### Logging exceptions with translation support
+
+Translation support applies to `HomeAssistantError` and subclasses like `ServiceValidationError`. When a `translation_domain` and `translation_key` is set and the error message is added in `strings.json`, it is no longer needed to add the error message string for the local logging. Home Assistant will automatically fetch the English error message from the translation cache.
+
+When raising `HomeAssistantError` or a subclass with translation support we should remove the log message from the argument list to enable it to be fetched from the translation cache.
+
+For example:
+
+```python
+async def async_select_index(hass: HomeAssistant, index: int) -> None:
+    """Setup the config entry for my device."""
+    try:
+        check_index(index)
+    except ValueError as exc:
+        raise ServiceValidationError(
+            translation_domain=DOMAIN,
+            translation_key="invalid_index",
+            translation_placeholders={
+                "index": index,
+                "expected": expected,
+            },
+        ) from exc
+```
+
+The error message is placed in `strings.json`:
+
+```json
+{
+    ...
+    "exceptions": {
+        "invalid_index": {
+            "message": "An invalid index is selected, expected: {expected}, got: {index}"
+        }
+    }
+}
+```

docs/internationalization/core.md

@@ -188,7 +188,6 @@ async def async_select_index(hass: HomeAssistant, index: int) -> None:
         check_index(index)
     except ValueError as exc:
         raise ServiceValidationError(
-            str(exc),
             translation_domain=DOMAIN,
             translation_key="invalid_index",
             translation_placeholders={
@@ -197,7 +196,6 @@ async def async_select_index(hass: HomeAssistant, index: int) -> None:
         ) from exc
 ```
 
-
 ### Issues
 
 The translation strings for repairs issues are defined under the `issues` key. An example strings file below describes the different supported keys.