Removed sync arg from wandb.log (#3472)

Fixes #3471 

Description:
Remove the `sync` argument from the `wandb.log()` calls in the
OutputHandler and OptimizerParamsHandler, since the argument was
removed. Kept the argument in the initialisation of the handlers, so
that existing code that may include the argument keeps working.

Check list:

- [ ] New tests are added (if a new feature is added)
- [ ] New doc strings: description and/or example code are in RST format
- [x] Documentation is updated (if required)

Author: DanielNobbe

ignite/handlers/wandb_logger.py

@@ -1,6 +1,7 @@
 """WandB logger and its helper handlers."""
 
 from typing import Any, Callable, List, Optional, Union
+from warnings import warn
 
 from torch.optim import Optimizer
 
@@ -172,8 +173,7 @@ class OutputHandler(BaseOutputHandler):
             Default is None, global_step based on attached engine. If provided,
             uses function output as global_step. To setup global step from another engine, please use
             :meth:`~ignite.handlers.wandb_logger.global_step_from_engine`.
-        sync: If set to False, process calls to log in a seperate thread. Default (None) uses whatever
-            the default value of wandb.log.
+        sync: Deprecated, has no function. Argument is kept here for compatibility with existing code.
 
     Examples:
         .. code-block:: python
@@ -284,7 +284,8 @@ def __init__(
         state_attributes: Optional[List[str]] = None,
     ):
         super().__init__(tag, metric_names, output_transform, global_step_transform, state_attributes)
-        self.sync = sync
+        if sync is not None:
+            warn("The sync argument for the WandBLoggers is no longer used, and may be removed in the future")
 
     def __call__(self, engine: Engine, logger: WandBLogger, event_name: Union[str, Events]) -> None:
         if not isinstance(logger, WandBLogger):
@@ -298,7 +299,7 @@ def __call__(self, engine: Engine, logger: WandBLogger, event_name: Union[str, E
             )
 
         metrics = self._setup_output_metrics_state_attrs(engine, log_text=True, key_tuple=False)
-        logger.log(metrics, step=global_step, sync=self.sync)
+        logger.log(metrics, step=global_step)
 
 
 class OptimizerParamsHandler(BaseOptimizerParamsHandler):
@@ -309,8 +310,7 @@ class OptimizerParamsHandler(BaseOptimizerParamsHandler):
             as a sequence.
         param_name: parameter name
         tag: common title for all produced plots. For example, "generator"
-        sync: If set to False, process calls to log in a seperate thread. Default (None) uses whatever
-            the default value of wandb.log.
+        sync: Deprecated, has no function. Argument is kept here for compatibility with existing code.
 
     Examples:
         .. code-block:: python
@@ -346,7 +346,8 @@ def __init__(
         self, optimizer: Optimizer, param_name: str = "lr", tag: Optional[str] = None, sync: Optional[bool] = None
     ):
         super(OptimizerParamsHandler, self).__init__(optimizer, param_name, tag)
-        self.sync = sync
+        if sync is not None:
+            warn("The sync argument for the WandBLoggers is no longer used, and may be removed in the future")
 
     def __call__(self, engine: Engine, logger: WandBLogger, event_name: Union[str, Events]) -> None:
         if not isinstance(logger, WandBLogger):
@@ -358,4 +359,4 @@ def __call__(self, engine: Engine, logger: WandBLogger, event_name: Union[str, E
             f"{tag_prefix}{self.param_name}/group_{i}": float(param_group[self.param_name])
             for i, param_group in enumerate(self.optimizer.param_groups)
         }
-        logger.log(params, step=global_step, sync=self.sync)
+        logger.log(params, step=global_step)

tests/ignite/handlers/test_wandb_logger.py

@@ -31,14 +31,14 @@ def test_optimizer_params():
     mock_engine.state.iteration = 123
 
     wrapper(mock_engine, mock_logger, Events.ITERATION_STARTED)
-    mock_logger.log.assert_called_once_with({"lr/group_0": 0.01}, step=123, sync=None)
+    mock_logger.log.assert_called_once_with({"lr/group_0": 0.01}, step=123)
 
     wrapper = OptimizerParamsHandler(optimizer, param_name="lr", tag="generator")
     mock_logger = MagicMock(spec=WandBLogger)
     mock_logger.log = MagicMock()
 
     wrapper(mock_engine, mock_logger, Events.ITERATION_STARTED)
-    mock_logger.log.assert_called_once_with({"generator/lr/group_0": 0.01}, step=123, sync=None)
+    mock_logger.log.assert_called_once_with({"generator/lr/group_0": 0.01}, step=123)
 
 
 def test_output_handler_with_wrong_logger_type():
@@ -62,36 +62,14 @@ def test_output_handler_output_transform():
 
     wrapper(mock_engine, mock_logger, Events.ITERATION_STARTED)
 
-    mock_logger.log.assert_called_once_with({"tag/output": 12345}, step=123, sync=None)
+    mock_logger.log.assert_called_once_with({"tag/output": 12345}, step=123)
 
     wrapper = OutputHandler("another_tag", output_transform=lambda x: {"loss": x})
     mock_logger = MagicMock(spec=WandBLogger)
     mock_logger.log = MagicMock()
 
     wrapper(mock_engine, mock_logger, Events.ITERATION_STARTED)
-    mock_logger.log.assert_called_once_with({"another_tag/loss": 12345}, step=123, sync=None)
-
-
-def test_output_handler_output_transform_sync():
-    wrapper = OutputHandler("tag", output_transform=lambda x: x, sync=False)
-    mock_logger = MagicMock(spec=WandBLogger)
-    mock_logger.log = MagicMock()
-
-    mock_engine = MagicMock()
-    mock_engine.state = State()
-    mock_engine.state.output = 12345
-    mock_engine.state.iteration = 123
-
-    wrapper(mock_engine, mock_logger, Events.ITERATION_STARTED)
-
-    mock_logger.log.assert_called_once_with({"tag/output": 12345}, step=123, sync=False)
-
-    wrapper = OutputHandler("another_tag", output_transform=lambda x: {"loss": x}, sync=True)
-    mock_logger = MagicMock(spec=WandBLogger)
-    mock_logger.log = MagicMock()
-
-    wrapper(mock_engine, mock_logger, Events.ITERATION_STARTED)
-    mock_logger.log.assert_called_once_with({"another_tag/loss": 12345}, step=123, sync=True)
+    mock_logger.log.assert_called_once_with({"another_tag/loss": 12345}, step=123)
 
 
 def test_output_handler_metric_names():
@@ -104,7 +82,7 @@ def test_output_handler_metric_names():
     mock_engine.state.iteration = 5
 
     wrapper(mock_engine, mock_logger, Events.ITERATION_STARTED)
-    mock_logger.log.assert_called_once_with({"tag/a": 1, "tag/b": 5}, step=5, sync=None)
+    mock_logger.log.assert_called_once_with({"tag/a": 1, "tag/b": 5}, step=5)
 
     wrapper = OutputHandler("tag", metric_names=["a", "c"])
     mock_engine = MagicMock()
@@ -115,7 +93,7 @@ def test_output_handler_metric_names():
     mock_logger.log = MagicMock()
 
     wrapper(mock_engine, mock_logger, Events.ITERATION_STARTED)
-    mock_logger.log.assert_called_once_with({"tag/a": 55.56, "tag/c": "Some text"}, step=7, sync=None)
+    mock_logger.log.assert_called_once_with({"tag/a": 55.56, "tag/c": "Some text"}, step=7)
 
     # all metrics
     wrapper = OutputHandler("tag", metric_names="all")
@@ -127,7 +105,7 @@ def test_output_handler_metric_names():
     mock_engine.state.iteration = 5
 
     wrapper(mock_engine, mock_logger, Events.ITERATION_STARTED)
-    mock_logger.log.assert_called_once_with({"tag/a": 12.23, "tag/b": 23.45}, step=5, sync=None)
+    mock_logger.log.assert_called_once_with({"tag/a": 12.23, "tag/b": 23.45}, step=5)
 
     # log a torch vector
     wrapper = OutputHandler("tag", metric_names="all")
@@ -139,7 +117,7 @@ def test_output_handler_metric_names():
     mock_engine.state.iteration = 5
 
     wrapper(mock_engine, mock_logger, Events.ITERATION_STARTED)
-    mock_logger.log.assert_called_once_with({f"tag/a/{i}": vector[i].item() for i in range(5)}, step=5, sync=None)
+    mock_logger.log.assert_called_once_with({f"tag/a/{i}": vector[i].item() for i in range(5)}, step=5)
 
     wrapper = OutputHandler("tag", metric_names=["a"])
     mock_engine = MagicMock()
@@ -151,7 +129,7 @@ def test_output_handler_metric_names():
     mock_logger.log = MagicMock()
 
     wrapper(mock_engine, mock_logger, Events.ITERATION_STARTED)
-    mock_logger.log.assert_called_once_with({f"tag/a/{i}": v for i, v in enumerate(data)}, step=7, sync=None)
+    mock_logger.log.assert_called_once_with({f"tag/a/{i}": v for i, v in enumerate(data)}, step=7)
 
     wrapper = OutputHandler("tag", metric_names="all")
     mock_engine = MagicMock()
@@ -179,7 +157,6 @@ def test_output_handler_metric_names():
             "tag/c/2/e": 32.1,
         },
         step=7,
-        sync=None,
     )
 
 
@@ -195,7 +172,7 @@ def test_output_handler_both():
 
     wrapper(mock_engine, mock_logger, Events.EPOCH_STARTED)
 
-    mock_logger.log.assert_called_once_with({"tag/a": 12.23, "tag/b": 23.45, "tag/loss": 12345}, step=5, sync=None)
+    mock_logger.log.assert_called_once_with({"tag/a": 12.23, "tag/b": 23.45, "tag/loss": 12345}, step=5)
 
 
 def test_output_handler_with_wrong_global_step_transform_output():
@@ -229,7 +206,7 @@ def global_step_transform(*args, **kwargs):
     mock_engine.state.output = 12345
 
     wrapper(mock_engine, mock_logger, Events.EPOCH_STARTED)
-    mock_logger.log.assert_called_once_with({"tag/loss": 12345}, step=10, sync=None)
+    mock_logger.log.assert_called_once_with({"tag/loss": 12345}, step=10)
 
 
 def test_output_handler_with_global_step_from_engine():
@@ -254,7 +231,7 @@ def test_output_handler_with_global_step_from_engine():
 
     wrapper(mock_engine, mock_logger, Events.EPOCH_STARTED)
     mock_logger.log.assert_called_once_with(
-        {"tag/loss": mock_engine.state.output}, step=mock_another_engine.state.epoch, sync=None
+        {"tag/loss": mock_engine.state.output}, step=mock_another_engine.state.epoch
     )
 
     mock_another_engine.state.epoch = 11
@@ -263,7 +240,7 @@ def test_output_handler_with_global_step_from_engine():
     wrapper(mock_engine, mock_logger, Events.EPOCH_STARTED)
     assert mock_logger.log.call_count == 2
     mock_logger.log.assert_has_calls(
-        [call({"tag/loss": mock_engine.state.output}, step=mock_another_engine.state.epoch, sync=None)]
+        [call({"tag/loss": mock_engine.state.output}, step=mock_another_engine.state.epoch)]
     )
 
 
@@ -291,7 +268,6 @@ def test_output_handler_state_attrs():
             "tag/delta": "Some Text",
         },
         step=5,
-        sync=None,
     )