std_msgs/{Duration,Time} field mapping is failing

[rgov]

In #106 support was added to map std_msgs/{Duration,Time} to builtin_interfaces/{Duration,Time}. However, this is not working as expected for me for a field of type std_msgs/Duration.

I cannot follow the metaprogramming easily, but AI has summarized it as:

The Factory-based conversions work for direct topic bridging. But when code is generated for custom messages containing std_msgs/Duration fields, it emits calls to the free-standing ros1_bridge::convert_1_to_2() — which doesn't have a specialization for std_msgs::Duration, only ros::Duration.

I think the argument here is that it is missing specializations like the below, but for std_msgs/{Duration,Time}.

ros1_bridge/src/convert_builtin_interfaces.cpp

Lines 22 to 30 in 611755f

	template<>
	void
	convert_1_to_2(
	const ros::Duration & ros1_type,
	builtin_interfaces::msg::Duration & ros2_msg)
	{
	ros2_msg.sec = ros1_type.sec;
	ros2_msg.nanosec = ros1_type.nsec;
	}

There does seem to be some magic for mapping top-level topic types of std_msgs/{Duration,Time} but I don't think it works for field types?

ros1_bridge/src/bridge.cpp

Lines 56 to 58 in 611755f

	auto factory = get_factory(ros1_type_name, ros2_type_name);
	auto ros2_pub = factory->create_ros2_publisher(
	ros2_node, ros2_topic_name, publisher_qos);

[rgov]

Adding this .cpp file to the ros1_bridge sources resolves the issue for me:

// Custom converters for std_msgs/Duration and std_msgs/Time
// These provide template function specializations needed by auto-generated bridge code

#include "ros1_bridge/convert_builtin_interfaces.hpp"
#include <std_msgs/Duration.h>
#include <std_msgs/Time.h>
#include <builtin_interfaces/msg/duration.hpp>
#include <builtin_interfaces/msg/time.hpp>

namespace ros1_bridge {

// std_msgs/Duration converters
template<>
void convert_1_to_2(
  const std_msgs::Duration & ros1_msg,
  builtin_interfaces::msg::Duration & ros2_msg)
{
  ros2_msg.sec = ros1_msg.data.sec;
  ros2_msg.nanosec = ros1_msg.data.nsec;
}

template<>
void convert_2_to_1(
  const builtin_interfaces::msg::Duration & ros2_msg,
  std_msgs::Duration & ros1_msg)
{
  ros1_msg.data.sec = ros2_msg.sec;
  ros1_msg.data.nsec = ros2_msg.nanosec;
}

// std_msgs/Time converters
template<>
void convert_1_to_2(
  const std_msgs::Time & ros1_msg,
  builtin_interfaces::msg::Time & ros2_msg)
{
  ros2_msg.sec = ros1_msg.data.sec;
  ros2_msg.nanosec = ros1_msg.data.nsec;
}

template<>
void convert_2_to_1(
  const builtin_interfaces::msg::Time & ros2_msg,
  std_msgs::Time & ros1_msg)
{
  ros1_msg.data.sec = ros2_msg.sec;
  ros1_msg.data.nsec = ros2_msg.nanosec;
}

}  // namespace ros1_bridge