can map custom srv but msg

[AliothZhou]

Bug report

Required Info:

• Operating System: Ubuntu20.04
• Installation type: source
• Version or commit hash: foxy
• DDS implementation: fastDDS
• Client library (if applicable):

Steps to reproduce issue

here is my msg defined codes, code, then I clone ros1_bridge source code from github into ros2_ws/src, and I ran these cmds below

source /opt/ros/noetic/setup.bash \
    && cd ros1_ws \
    && catkin_make --only-pkg-with-deps bridge_interfaces

source /opt/ros/foxy/setup.bash \
    && ros2_ws \
    && colcon build --packages-up-to bridge_interfaces

source /opt/ros/noetic/setup.bash \
    && source /opt/ros/foxy/setup.bash \
    && source /ros1_ws/devel/setup.bash \
    && source ros2_ws/install/setup.bash \
    && cd ros2_ws \
    && colcon build --packages-select ros1_bridge --cmake-force-configure

Expected behavior

ros2 run ros1_bridge dynamic_bridge --print-pairs shows all customed msgs and srvs' conversions and bridge works.

Actual behavior

After these steps, I ran ros2 run ros1_bridge dynamic_bridge --print-pairs, and there was only arm_interfaces/srv/Motion.srv shows. But I can find all related msgs factory files generated in ros2_ws/build/ros1_bridge/generated. In this situation, after running ros2 run ros1_bridge dynamic_bridge and publishing related msgs, bridge does not work.

Additional information

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Feature request

Feature description

Implementation considerations