Add missing methods to logger collection

CHANGELOG.md

@@ -40,6 +40,8 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 
 - Fixed TPU multi-core and Float16 ([#2632](https://github.com/PyTorchLightning/pytorch-lightning/pull/2632))
 
+- Fixed test metrics not being logged with multiple loggers ([#2723](https://github.com/PyTorchLightning/pytorch-lightning/pull/2723))
+
 ## [0.8.5] - 2020-07-09
 
 ### Added

pytorch_lightning/loggers/base.py

@@ -272,10 +272,20 @@ def __init__(self, logger_iterable: Iterable[LightningLoggerBase]):
     def __getitem__(self, index: int) -> LightningLoggerBase:
         return [logger for logger in self._logger_iterable][index]
 
+    def update_agg_funcs(
+            self,
+            agg_key_funcs: Optional[Mapping[str, Callable[[Sequence[float]], float]]] = None,
+            agg_default_func: Callable[[Sequence[float]], float] = np.mean
+    ):
+        [logger.update_agg_funcs(agg_key_funcs, agg_default_func) for logger in self._logger_iterable]
+
     @property
     def experiment(self) -> List[Any]:
         return [logger.experiment for logger in self._logger_iterable]
 
+    def agg_and_log_metrics(self, metrics: Dict[str, float], step: Optional[int] = None):
+        [logger.agg_and_log_metrics(metrics, step) for logger in self._logger_iterable]
+
     def log_metrics(self, metrics: Dict[str, float], step: Optional[int] = None) -> None:
         [logger.log_metrics(metrics, step) for logger in self._logger_iterable]
 
@@ -291,6 +301,11 @@ def finalize(self, status: str) -> None:
     def close(self) -> None:
         [logger.close() for logger in self._logger_iterable]
 
+    @property
+    def save_dir(self) -> Optional[str]:
+        # Checkpoints should be saved to default / chosen location when using multiple loggers
+        return None
+
     @property
     def name(self) -> str:
         return '_'.join([str(logger.name) for logger in self._logger_iterable])

tests/loggers/test_base.py

@@ -22,6 +22,16 @@ def test_logger_collection():
     assert logger.experiment[0] == mock1.experiment
     assert logger.experiment[1] == mock2.experiment
 
+    assert logger.save_dir is None
+
+    logger.update_agg_funcs({'test': np.mean}, np.sum)
+    mock1.update_agg_funcs.assert_called_once_with({'test': np.mean}, np.sum)
+    mock2.update_agg_funcs.assert_called_once_with({'test': np.mean}, np.sum)
+
+    logger.agg_and_log_metrics({'test': 2.0}, 4)
+    mock1.agg_and_log_metrics.assert_called_once_with({'test': 2.0}, 4)
+    mock2.agg_and_log_metrics.assert_called_once_with({'test': 2.0}, 4)
+
     logger.close()
     mock1.close.assert_called_once()
     mock2.close.assert_called_once()