change rclcpp logger sink or get all the sinks used by rclcpp

[dxg397]

trafficstars

I have been trying to change the rclcpp logger sink to a rotating sink which is then be connected using fluentd to log to Elasticsearch. Is there any way to do this? I can do it if I used spdlog library but cannot do with external ROS libraries I am using.

• Operating System: -Ubuntu 22.04
• Installation type:
  • from source using bazel
• Client library (if applicable):
  • rclcpp::logger or MARCOS --> RCLCPP_INFO();

Expected behavior

the sink is defined as this:- ---> std::make_sharedspdlog::sinks::rotating_file_sink_mt("/tmp/log/temp.log", 1048576 * 5, 1);

Actual behavior

spdlog is not able to find the loggers registered with rclcpp library even though it uses spdlog as the base.

Feature request

Maybe having a conversion function to convert from rclcpp logger to base spdlog logger spdlog::logger convertTospdLogger(rclcpp::logger) {}

[fujitatomoya]

spdlog is not able to find the loggers registered with rclcpp library even though it uses spdlog as the base.

no, this is what we cannot do right now with rcl_logging_spdlog. it statically uses spdlog::sinks::basic_file_sink_mt only.

https://github.com/ros2/rcl_logging/blob/014239dd80ab3de2a847af80f23d24da6438ecb7/rcl_logging_spdlog/src/rcl_logging_spdlog.cpp#L177

actually rclcpp (precisely rcl) does not know logging implementation but rcl_logging_interface. that means user can create own implementation to support those interfaces for ROS 2 logger. (we actually do this with our proprietary lock-free in-memory logger implementation.)

probably easiest way for you would be to replace spdlog::sinks::basic_file_sink_mt into spdlog::sinks::rotating_file_sink_mt in source code, and build it with your colcon workspace.

for long term, there is parameter argument --log-config-file with ros2 command to load the external logger configuration to the logger implementation. so that in rcl_logging_xxx can set up the configuration based on this config file. but it is not supported yet for rcl_logging_spdlog.

https://github.com/ros2/rcl_logging/blob/014239dd80ab3de2a847af80f23d24da6438ecb7/rcl_logging_spdlog/src/rcl_logging_spdlog.cpp#L107-L111

it would be appreciated if you consider the contribution, but we would want to have discussion what setting configuration should be supported for rcl_logging_spdlog.

[fujitatomoya]

@clalancette i think we can move this issue to https://github.com/ros2/rcl_logging. what do you think?

[jrutgeer]

we actually do this with our proprietary lock-free in-memory logger implementation

Interesting. Any chance on open-sourcing that one?

[fujitatomoya]

unfortunately no, we do not have any plan for that.