adding a ProgressHandler

docs/source/plugins/developing_plugins.rst

@@ -1198,6 +1198,26 @@ using the pattern show below:
 
         ctx.dataset.add_images_dir(images_dir, progress=progress)
 
+You can also use the builtin
+:class:`ProgressHandler <fiftyone.operators.ProgressHandler>` class to
+automatically forward logging messages to
+:meth:`set_progress() <fiftyone.operators.executor.ExecutionContext.set_progress>`
+as `label` values using the pattern shown below:
+
+.. code-block:: python
+    :linenos:
+
+    import logging
+    import fiftyone.operators as foo
+    import fiftyone.zoo as foz
+
+    def execute(self, ctx):
+        name = ctx.params["name"]
+
+        # Automatically report all `fiftyone` logging messages
+        with foo.ProgressHandler(ctx, logger=logging.getLogger("fiftyone")):
+            foz.load_zoo_dataset(name, persistent=True)
+
 .. _operator-execution:
 
 Operator execution

fiftyone/operators/__init__.py

@@ -16,6 +16,7 @@
     execute_operator,
     ExecutionOptions,
 )
+from .utils import ProgressHandler
 
 # This enables Sphinx refs to directly use paths imported here
 __all__ = [k for k, v in globals().items() if not k.startswith("_")]

fiftyone/operators/utils.py

@@ -0,0 +1,50 @@
+"""
+FiftyOne operator utilities.
+
+| Copyright 2017-2023, Voxel51, Inc.
+| `voxel51.com <https://voxel51.com/>`_
+|
+"""
+import logging
+
+
+class ProgressHandler(logging.Handler):
+    """A logging handler that reports all logging messages issued while the
+    handler's context manager is active to the provided execution context's
+    :meth:`set_progress() <fiftyone.operators.executor.ExecutionContext.set_progress>`
+    method.
+
+    Args:
+        ctx: an :class:`fiftyone.operators.executor.ExecutionContext`
+        logger (None): a specific ``logging.Logger`` for which to report
+            records. By default, the root logger is used
+        level (None): an optional logging level above which to report records.
+            By default, the logger's effective level is used
+    """
+
+    def __init__(self, ctx, logger=None, level=None):
+        super().__init__()
+        self.ctx = ctx
+        self.logger = logger
+        self.level = level
+
+    def __enter__(self):
+        if self.logger is None:
+            self.logger = logging.getLogger()
+
+        if self.level is None:
+            self.level = self.logger.getEffectiveLevel()
+
+        self.setLevel(self.level)
+        self.logger.addHandler(self)
+
+    def __exit__(self, *args):
+        try:
+            self.logger.removeHandler(self)
+        except:
+            pass
+
+    def emit(self, record):
+        msg = self.format(record)
+        print(f"****** {msg} ******")
+        self.ctx.set_progress(label=msg)