ROS2 disable logging to file

edit

Okay so I found a solution by creating a replacement for ros2 launch. Just put the following into a Python script like quiet_launch.py and use it in place of ros2 launch to launch your launch file. I hope this comes in handy for anyone looking for a way to turn off all log file generation. Only tested on an old version of foxy.

# STEP 1

# Instead of creating a unique directory for logs, leave it up to the user.
# Here we're just making the dir if it doesn't exist.
# Log dir should be set through the ROS_LOG_DIR env var.

from launch import logging

import os


def make_log_dir(*, base_path):
    os.makedirs(base_path, exist_ok=True)

    return base_path


logging._make_unique_log_dir = make_log_dir

# STEP 2

# Replace the log file handler used by `launch` with any log file handler
# you want. Here we're using NullHandler so `launch` doesn't log to file.

# It's unfortunate there is no type completion here but we need the wrapped version
# of the log file handler from `launch`. Refer module launch.logging.handlers.
# For full list of handlers, refer module logging.handlers.

from launch.logging.handlers import NullHandler

logging.launch_config.log_handler_factory = lambda path, encoding=None: NullHandler()

# Here's an example of setting up a timed rotating file handler:

# from launch.logging.handlers import TimedRotatingFileHandler

# logging.launch_config.log_handler_factory = (
#     lambda path, encoding=None: TimedRotatingFileHandler(
#         path, when="S", interval=10, backupCount=3, encoding=encoding
#     )
# )

# STEP 3

# Make sure you set your log output type when launching your node. I.e.
# output='screen'. Refer to options below.

# You can override all node setting by setting the env var as below:
# OVERRIDE_LAUNCH_PROCESS_OUTPUT='screen'

# - 'screen': stdout and stderr are logged to the screen,
# - 'log': stdout and stderr are logged to launch log file and stderr to
#       the screen,
# - 'both': both stdout and stderr are logged to the screen and to launch
#       main log file,
# - 'own_log' for stdout, stderr and their combination to be logged to
#       their own log files, and
# - 'full' to have stdout and stderr sent to the screen, to the main launch
#       log file, and their own separate and combined log files.

# STEP 4

# For C++ nodes, if you want to disable file logging you need to pass `ros-arg`
# `disable-external-lib-logs`. Due to a bug in launch_ros.actions.node (line 180)
# you need to manually prepend "--ros-args" for the argument to be processed. I.e.:

# arguments=[
#     "--ros-args",
#     "--disable-external-lib-logs",
# ],

# STEP 5

# When you launch a lifecycle node, `launch_ros.ros_adapters` creates a node
# for lifecycle-node-specific features to be started (i.e. a '/change_state'
# service is created). Unfortunately, no mechanism has been provided to pass
# ros-args to rclpy.init when it is called.
# Here we patch the module to insert the ros-args we want so a log file isn't
# created by `launch_ros`.

from launch_ros import ros_adapters


class MyROSAdapter(ros_adapters.ROSAdapter):
    def __init__(self, *, argv=None, autostart=True):
        argv = [] if argv is None else argv
        argv.extend(["--ros-args", "--disable-external-lib-logs"])
        super().__init__(argv=argv, autostart=autostart)


ros_adapters.ROSAdapter = MyROSAdapter

# STEP 6

# Implement the bare-minimum needed ...