bump: transmission to use neptune only, drop neptune-client (#19265)

* bump: min version `neptune>=1.0.0`
* Apply suggestions from code review

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Carlos Mocholí <carlossmocholi@gmail.com>

requirements/pytorch/loggers.info

@@ -1,6 +1,6 @@
 # all supported loggers. this list is here as a reference, but they are not installed in CI
 
-neptune
+neptune >=1.0.0
 comet-ml >=3.31.0
 mlflow >=1.0.0
 wandb >=0.12.10

src/lightning/pytorch/loggers/neptune.py

@@ -39,9 +39,12 @@
 
 log = logging.getLogger(__name__)
 
-# neptune is available with two names on PyPI : `neptune` and `neptune-client`
+# Neptune is available with two names on PyPI : `neptune` and `neptune-client`
+# `neptune` was introduced as a name transition of neptune-client and the long-term target is to get
+# rid of Neptune-client package completely someday. It was introduced as a part of breaking-changes with a release
+# of neptune-client==1.0. neptune-client>=1.0 is just an alias of neptune package and have some breaking-changes
+# in compare to neptune-client<1.0.0.
 _NEPTUNE_AVAILABLE = RequirementCache("neptune>=1.0")
-_NEPTUNE_CLIENT_AVAILABLE = RequirementCache("neptune-client")
 _INTEGRATION_VERSION_KEY = "source_code/integrations/pytorch-lightning"
 
 
@@ -224,8 +227,9 @@ def __init__(
         prefix: str = "training",
         **neptune_run_kwargs: Any,
     ):
-        if not _NEPTUNE_AVAILABLE and not _NEPTUNE_CLIENT_AVAILABLE:
+        if not _NEPTUNE_AVAILABLE:
             raise ModuleNotFoundError(str(_NEPTUNE_AVAILABLE))
+
         # verify if user passed proper init arguments
         self._verify_input_arguments(api_key, project, name, run, neptune_run_kwargs)
         super().__init__()
@@ -254,10 +258,7 @@ def __init__(
             root_obj[_INTEGRATION_VERSION_KEY] = pl.__version__
 
     def _retrieve_run_data(self) -> None:
-        if _NEPTUNE_AVAILABLE:
-            from neptune.handler import Handler
-        else:
-            from neptune.new.handler import Handler
+        from neptune.handler import Handler
 
         assert self._run_instance is not None
         root_obj = self._run_instance
@@ -310,12 +311,9 @@ def _verify_input_arguments(
         run: Optional[Union["Run", "Handler"]],
         neptune_run_kwargs: dict,
     ) -> None:
-        if _NEPTUNE_AVAILABLE:
-            from neptune import Run
-            from neptune.handler import Handler
-        else:
-            from neptune.new import Run
-            from neptune.new.handler import Handler
+        from neptune import Run
+        from neptune.handler import Handler
+
         # check if user passed the client `Run`/`Handler` object
         if run is not None and not isinstance(run, (Run, Handler)):
             raise ValueError("Run parameter expected to be of type `neptune.Run`, or `neptune.handler.Handler`.")
@@ -335,10 +333,7 @@ def __getstate__(self) -> Dict[str, Any]:
         return state
 
     def __setstate__(self, state: Dict[str, Any]) -> None:
-        if _NEPTUNE_AVAILABLE:
-            import neptune
-        else:
-            import neptune.new as neptune
+        import neptune
 
         self.__dict__ = state
         self._run_instance = neptune.init_run(**self._neptune_init_args)
@@ -376,10 +371,7 @@ def training_step(self, batch, batch_idx):
     @property
     @rank_zero_experiment
     def run(self) -> "Run":
-        if _NEPTUNE_AVAILABLE:
-            import neptune
-        else:
-            import neptune.new as neptune
+        import neptune
 
         if not self._run_instance:
             self._run_instance = neptune.init_run(**self._neptune_init_args)
@@ -426,10 +418,7 @@ def log_hyperparams(self, params: Union[Dict[str, Any], Namespace]) -> None:
             neptune_logger.log_hyperparams(PARAMS)
 
         """
-        if _NEPTUNE_AVAILABLE:
-            from neptune.utils import stringify_unsupported
-        else:
-            from neptune.new.utils import stringify_unsupported
+        from neptune.utils import stringify_unsupported
 
         params = _convert_params(params)
         params = _sanitize_callable_params(params)
@@ -485,10 +474,7 @@ def save_dir(self) -> Optional[str]:
 
     @rank_zero_only
     def log_model_summary(self, model: "pl.LightningModule", max_depth: int = -1) -> None:
-        if _NEPTUNE_AVAILABLE:
-            from neptune.types import File
-        else:
-            from neptune.new.types import File
+        from neptune.types import File
 
         model_str = str(ModelSummary(model=model, max_depth=max_depth))
         self.run[self._construct_path_with_prefix("model/summary")] = File.from_content(
@@ -507,10 +493,7 @@ def after_save_checkpoint(self, checkpoint_callback: Checkpoint) -> None:
         if not self._log_model_checkpoints:
             return
 
-        if _NEPTUNE_AVAILABLE:
-            from neptune.types import File
-        else:
-            from neptune.new.types import File
+        from neptune.types import File
 
         file_names = set()
         checkpoints_namespace = self._construct_path_with_prefix("model/checkpoints")