Plumb status updates through event handler

This will allow users to disable the event handler and silence the
currently unconditional console output.

Author: cottsay

colcon_parallel_executor/event/__init__.py

@@ -0,0 +1,16 @@
+# Copyright 2025 Open Source Robotics Foundation, Inc.
+# Licensed under the Apache License, Version 2.0
+
+
+class ParallelStatus:
+    """An event containing the identifiers of in-progress jobs."""
+
+    __slots__ = ('processing', )
+
+    def __init__(self, processing):
+        """
+        Construct a ParallelStatus.
+
+        :param processing list: The in-progress job identifiers
+        """
+        self.processing = tuple(processing)

colcon_parallel_executor/event/executor.py

@@ -0,0 +1,32 @@
+# Copyright 2025 Open Source Robotics Foundation, Inc.
+# Licensed under the Apache License, Version 2.0
+
+import sys
+
+from colcon_core.event_handler import EventHandlerExtensionPoint
+from colcon_core.plugin_system import satisfies_version
+from colcon_parallel_executor.event.executor import ParallelStatus
+
+
+class ParallelStatusEventHandler(EventHandlerExtensionPoint):
+    """
+    Periodically print a reminder of the currently executing jobs.
+
+    This extension is only enabled by default if stdout is a tty-like device.
+
+    This extension handles events of the following types:
+    - :py:class:`colcon_parallel_executor.event.executor.ParallelStatus`
+    """
+
+    def __init__(self):  # noqa: D107
+        super().__init__()
+        satisfies_version(
+            EventHandlerExtensionPoint.EXTENSION_POINT_VERSION, '^1.0')
+
+        self.enabled = sys.stdout.isatty()
+
+    def __call__(self, event):  # noqa: D102
+        data = event[0]
+
+        if isinstance(data, ParallelStatus):
+            print(f"[Processing: {', '.join(sorted(data.processing))}]")

colcon_parallel_executor/event_handler/__init__.py

@@ -17,6 +17,7 @@
 from colcon_core.plugin_system import satisfies_version
 from colcon_core.subprocess import new_event_loop
 from colcon_core.subprocess import SIGINT_RESULT
+from colcon_parallel_executor.event.executor import ParallelStatus
 
 logger = colcon_logger.getChild(__name__)
 
@@ -43,7 +44,7 @@ class ParallelExecutorExtension(ExecutorExtensionPoint):
     def __init__(self):  # noqa: D107
         super().__init__()
         satisfies_version(
-            ExecutorExtensionPoint.EXTENSION_POINT_VERSION, '^1.0')
+            ExecutorExtensionPoint.EXTENSION_POINT_VERSION, '^1.1')
 
     def add_arguments(self, *, parser):  # noqa: D102
         max_workers_default = os.cpu_count() or 4
@@ -162,9 +163,8 @@ async def _execute(self, args, jobs, *, on_error):
                 futures.keys(), timeout=30, return_when=FIRST_COMPLETED)
 
             if not done_futures:  # timeout
-                print(
-                    '[Processing: %s]' % ', '.join(sorted(
-                        f.identifier for f in futures.values())))
+                self.put_event_into_queue(ParallelStatus(tuple(
+                    f.identifier for f in futures.values())))
 
             # check results of done futures
             for done_future in done_futures:

colcon_parallel_executor/event_handler/parallel_status.py

@@ -27,7 +27,7 @@ keywords = colcon
 [options]
 python_requires = >=3.6
 install_requires =
-  colcon-core>=0.3.15
+  colcon-core>=0.19.0
 packages = find:
 zip_safe = true
 
@@ -62,6 +62,8 @@ markers =
     linter
 
 [options.entry_points]
+colcon_core.event_handler =
+    parallel_status = colcon_parallel_executor.event_handler.parallel_status:ParallelStatusEventHandler
 colcon_core.executor =
     parallel = colcon_parallel_executor.executor.parallel:ParallelExecutorExtension
 

colcon_parallel_executor/executor/parallel.py

@@ -1,6 +1,6 @@
 [colcon-parallel-executor]
 No-Python2:
-Depends3: python3-colcon-core (>= 0.3.15)
+Depends3: python3-colcon-core (>= 0.19.0)
 Suite: focal jammy noble bookworm trixie
 X-Python3-Version: >= 3.6
 Debian-Version: 100

setup.cfg

@@ -6,6 +6,7 @@ coroutine
 getaffinity
 getpid
 getsignal
+isatty
 iscoroutinefunction
 iterdir
 linter