Flatten log stream error handling (#7340)

The client write errors in advanced_logs_handler() were handled in a try
nested inside the log reading loop, with each handler ending the loop.
Handle them in the outer try instead to remove a level of nesting. The
reader side only raises exceptions that none of the moved handlers catch.

ClientConnectionResetError subclasses ConnectionResetError, so its handler
has to stay ahead of the one for systemd-journal-gatewayd errors.

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

Author: agners

supervisor/api/host.py

@@ -390,29 +390,21 @@ async def advanced_logs_handler(
                 async for cursor, line in journal_logs_reader(
                     resp, log_formatter, no_colors
                 ):
-                    try:
-                        if not headers_returned:
-                            if cursor:
-                                response.headers["X-First-Cursor"] = cursor
-                            response.headers["X-Accel-Buffering"] = "no"
-                            await response.prepare(request)
-                            headers_returned = True
-                        await response.write(line.encode("utf-8") + b"\n")
-                    except ClientConnectionResetError as err:
-                        # When client closes the connection while reading busy logs, we
-                        # sometimes get this exception. It should be safe to ignore it.
-                        _LOGGER.debug(
-                            "ClientConnectionResetError raised when returning journal logs: %s",
-                            err,
-                        )
-                        break
-                    except ConnectionError as err:
-                        _LOGGER.warning(
-                            "%s raised when returning journal logs: %s",
-                            type(err).__name__,
-                            err,
-                        )
-                        break
+                    if not headers_returned:
+                        if cursor:
+                            response.headers["X-First-Cursor"] = cursor
+                        response.headers["X-Accel-Buffering"] = "no"
+                        await response.prepare(request)
+                        headers_returned = True
+                    await response.write(line.encode("utf-8") + b"\n")
+            except ClientConnectionResetError as err:
+                # When client closes the connection while reading busy logs, we
+                # sometimes get this exception. It should be safe to ignore it.
+                # Must precede the ConnectionResetError handler, it's a subclass.
+                _LOGGER.debug(
+                    "ClientConnectionResetError raised when returning journal logs: %s",
+                    err,
+                )
             except (ConnectionResetError, ClientPayloadError) as ex:
                 # If the stream to the client already started, an error response
                 # can no longer be sent, so just end the stream. This happens
@@ -427,6 +419,12 @@ async def advanced_logs_handler(
                     type(ex).__name__,
                     ex,
                 )
+            except ConnectionError as err:
+                _LOGGER.warning(
+                    "%s raised when returning journal logs: %s",
+                    type(err).__name__,
+                    err,
+                )
         return response
 
     @api_process_raw(CONTENT_TYPE_TEXT, error_type=CONTENT_TYPE_TEXT)