Use get_running_loop() instead of str cmp to check for a running event loop

Signed-off-by: Mathias L. Baumann <[email protected]>

Author: Marenz

src/frequenz/sdk/_internal/_asyncio.py

@@ -46,12 +46,10 @@ async def run_forever(
     while True:
         try:
             await async_callable()
-        except RuntimeError as exc:
-            if "no running event loop" in str(exc):
-                _logger.exception(
-                    "Something went wrong, no running event loop, skipping execution of %s",
-                    async_callable.__name__,
-                )
+        except RuntimeError:
+            try:
+                asyncio.get_running_loop()
+            except RuntimeError:
                 return
         except Exception:  # pylint: disable=broad-except
             if not asyncio.get_event_loop().is_running():

src/frequenz/sdk/actor/_actor.py

@@ -105,15 +105,16 @@ async def _run_loop(self) -> None:
                 _logger.info("Actor %s: Cancelled.", self)
                 raise
             except Exception as exc:  # pylint: disable=broad-except
-                if isinstance(exc, RuntimeError) and "no running event loop" in str(
-                    exc
-                ):
-                    _logger.exception(
-                        "Something went wrong, no running event loop,"
-                        " not trying to restart %s again.",
-                        self,
-                    )
-                    break
+                if isinstance(exc, RuntimeError):
+                    try:
+                        asyncio.get_running_loop()
+                    except RuntimeError:
+                        _logger.exception(
+                            "Something went wrong, no running event loop,"
+                            " not trying to restart %s again.",
+                            self,
+                        )
+                        break
                 if self._is_cancelled:
                     # If actor was cancelled, but any tasks have failed with an exception
                     # other than asyncio.CancelledError, those exceptions are combined