rule can be a message mapping and a field_mapping

[mikaelarguedas]

This is now ready for review with steps to reproduce and test

Connects to #134

[dirk-thomas]

LGTM. I don't see why fields_1_to_2 was being constrained here. It is later used through is_field_mapping to determine how to map the fields.

[mikaelarguedas]

How to reproduce the issue and test the fix:

Build environment:

Shell 1 (setup a container)

docker pull osrf/ros2:bouncy-ros1-bridge && docker run -it --rm osrf/ros2:bouncy-ros1-bridge
# apt update && apt install -y git python3-colcon-common-extensions build-essential
# cd && git clone https://github.com/mikaelarguedas/ros1_bridge_bug.git

Shell 2: (log in container and build ros1 workspace)

docker exec -it <CONTAINER_ID> bash

cd ~/ros1_bridge_bug/ros1_msgs_overlay/
source /opt/ros/melodic/setup.bash 
catkin_make_isolated --install

Shell 3: log in container and build ros2 ws

docker exec -it <CONTAINER_ID> bash

source /opt/ros/bouncy/setup.bash
cd ~/ros1_bridge_bug/ros2_msgs_overlay/
colcon build

Shell 4: log in container and build custom bridge

docker exec -it <CONTAINER_ID> bash

mkdir -p ~/ros1_bridge_bug/ros1_bridge_ws/src && cd ~/ros1_bridge_bug/ros1_bridge_ws/src
git clone https://github.com/ros2/ros1_bridge.git
cd ~/ros1_bridge_bug/ros1_bridge_ws
source /opt/ros/melodic/setup.bash 
source /opt/ros/bouncy/setup.bash 
source ~/ros1_bridge_bug/ros1_msgs_overlay/install_isolated/setup.bash 
source ~/ros1_bridge_bug/ros2_msgs_overlay/install/setup.bash
colcon build --event-handlers console_direct+

Confirm the absence of mapping:

cat build/ros1_bridge/generated/ros2_msgs_factories.hpp

File content without mapping

// generated from ros1_bridge/resource/pkg_factories.hpp.em

#include <ros1_bridge/factory.hpp>

// include ROS 1 messages

// include ROS 2 messages

namespace ros1_bridge
{

std::shared_ptr<FactoryInterface>
get_factory_ros2_msgs(const std::string & ros1_type_name, const std::string & ros2_type_name);

std::unique_ptr<ServiceFactoryInterface>
get_service_factory_ros2_msgs(const std::string & ros_id, const std::string & package_name, const std::string & service_name);

// conversion functions for available interfaces
}  // namespace ros1_bridge

Rebuild the bridge with this fix:

cd ~/ros1_bridge_bug/ros1_bridge_ws && rm -rf build install
cd ~/ros1_bridge_bug/ros1_bridge_ws/src/ros1_bridge && git checkout -t origin/fix_message_and_field_mapping && cd ~/ros1_bridge_bug/ros1_bridge_ws
colcon build --event-handlers console_direct+

Confirm the presence of mapping:

cat build/ros1_bridge/generated/ros2_msgs_factories.hpp

File content with mapping

// generated from ros1_bridge/resource/pkg_factories.hpp.em

#include <ros1_bridge/factory.hpp>

// include ROS 1 messages
#include <ros1_msgs/EgoData.h>

// include ROS 2 messages
#include <ros2_msgs/msg/size.hpp>

namespace ros1_bridge
{

std::shared_ptr<FactoryInterface>
get_factory_ros2_msgs(const std::string & ros1_type_name, const std::string & ros2_type_name);

std::unique_ptr<ServiceFactoryInterface>
get_service_factory_ros2_msgs(const std::string & ros_id, const std::string & package_name, const std::string & service_name);

// conversion functions for available interfaces

template<>
void
Factory<
  ros1_msgs::EgoData,
  ros2_msgs::msg::Size
>::convert_1_to_2(
  const ros1_msgs::EgoData & ros1_msg,
  ros2_msgs::msg::Size & ros2_msg);

template<>
void
Factory<
  ros1_msgs::EgoData,
  ros2_msgs::msg::Size
>::convert_2_to_1(
  const ros2_msgs::msg::Size & ros2_msg,
  ros1_msgs::EgoData & ros1_msg);

}  // namespace ros1_bridge

Test that bridging now works

Note: each shell is assumed to be a new shell in the container with nothing sourced in it

Shell a:

source /opt/ros/melodic/setup.bash
roscore

Shell b:

source /opt/ros/melodic/setup.bash 
source ~/ros1_bridge_bug/ros1_msgs_overlay/install_isolated/setup.bash 
source /opt/ros/bouncy/setup.bash 
source ~/ros1_bridge_bug/ros2_msgs_overlay/install/setup.bash 
source ~/ros1_bridge_bug/ros1_bridge_ws/install/setup.bash 
ros2 run ros1_bridge dynamic_bridge

Shell c:

apt install ros-melodic-rostopic
source /opt/ros/melodic/setup.bash 
source ~/ros1_bridge_bug/ros1_msgs_overlay/install_isolated/setup.bash 
rostopic pub /foo ros1_msgs/EgoData "vehicleLength: 0.0"

Shell d:

source ~/ros1_bridge_bug/ros2_msgs_overlay/install/setup.bash 
source /opt/ros/bouncy/setup.bash 
source ~/ros1_bridge_bug/ros2_msgs_overlay/install/setup.bash
ros2 topic echo /foo ros2_msgs/Size

You should see the bridged message printed:

length: 0.0

CI

Just regular packaging CI to make sure everything else works as before: