ROS 1 API adapters to facilitate migration

Next Generation ROS
1

Has anyone made much progress on an API adapter solution for ROS 1->2? I know the officially-blessed solution for migration is the ros1_bridge package, but this still requires that entire processes be moved over at once, which is a barrier for us. I recall there being discussions early on about some kind of compile-time adapter; I’m curious if anyone ever did a deeper exploration of this potential direction.

In particular, I’m wondering about a solution where roscpp is hollowed out so that the existing user-facing API implementation remains, but replacements implementations are introduced for TopicManager and ServiceManager which do the message translation and then publish via rclcpp.

2

The goal of the bridge is precisely not to have to move everything at once, but step by step, but maybe I am misreading your comment?

Here is how I am seeing a reasonable transition plan:

  • current state: (everything ROS 1)
  • step 1, add the bridge: (everything ROS 1) + bridge
  • step 2, port 1 node: (everything ROS 1 except the node ported to ROS 2) + bridge + (one ROS 2 node)
  • repeat until everything is ported: bridge + (everything in ROS2)
  • final step: stop running the bridge

Then, for the actual port, you can try using https://github.com/awslabs/ros2-migration-tools

This is using the clang Python API to try to apply source code transformations to migrate ROS 1 code to ROS 2 automatically. It can’t handle all cases, but it could help automating some of the process.

3

Ah, thanks for the point to ros2-migration-tools; that looks like it could be quite helpful.

Certainly ros1_bridge has its place; for a variety of reasons it’s not suitable as a migration path for our system, and the purpose of this thread is to understand if others have come to a similar conclusion about their systems and to what depth alternative approaches have been explored.

4

It looks like the last time this was discussed was a year and a half ago.

5

I heard rumors at the ROS-I America meeting about a second automated conversion tool from ROS 1 to ROS 2. It isn’t any magic, just a set of scripts/regex to automate a lot of the conversion grunt work. I am not sure if it is the same set of tooling or a second effort. I am going to follow up on it. I am curious if we could get a community initiative to build some tooling to help make the conversion effort a lot easier.

If you are in the process of doing a ROS 1 to ROS 2 conversion I would love to hear about your experiences and what you learned. I think in conjunction with the Foxy release I want to try and put together a best practices guide for those migrating deployed systems from ROS 1 to ROS 2.