NoDL - Node Definition Language

NoDL (Node Definition Language) is a schema and toolkit to describe a ROS 2 node's interface: parameters, topics (publishers and subscriptions), services (clients and servers), and actions (clients and servers).

Find complete documentation at https://nodl.readthedocs.io/en/latest/

Repository structure

• ament_nodl/: CMake macros to register NoDL documents with the ament index
• nodl/: Metapackage that pulls in the other packages as dependencies. Acts as an easy default for those who don't want a-la-carte.
  • doc/: Documentation source for the ReadTheDocs page
• nodl_schema/: Package providing the NoDL schema, plus a Python package with validation tools and typed data model to work with it. nodl.schema.yaml: The NoDL schema, key to this whole thing!
• nodl_observe/: C++ (ament_cmake) package that observes a running ROS 2 node and produces its runtime interface as a rosgraph_msgs/Node message — a reusable observe_node(...) library plus an observe executable. Stage one of Observe → Describe.
• ros2nodl/: ros2cli extension providing ros2 nodl ... commands
• tools/: Scripts supporting development and build workflows

Developing

Setup

1. Clone the repo and install pre-commit hooks:

pre-commit install
pre-commit install --hook-type prepare-commit-msg

The prepare-commit-msg hook will automatically add the Signed-off-by line to your commits. If you prefer to sign off manually, use git commit -s.