jig_cli

CLI tools for discovering and querying jig node interfaces at runtime.

jig_cli provides the jig command, which scans your ROS 2 workspace for installed jig interface definitions and outputs them as JSON or YAML. This is useful for launch systems, developer tooling, and any automation that needs to know what interfaces a node exposes.

Installation

pip

pip install "git+https://github.com/nineyards-robotics/jig.git#subdirectory=jig_cli"

From source

jig_cli is a standard ament_python package. Build it alongside the rest of your workspace:

colcon build --packages-select jig_cli
source install/setup.bash

Usage

jig interface – look up a single node

Retrieve the interface definition for a specific node by executable name or plugin class:

# By executable name
jig interface --package my_package --executable my_node

# By C++ component plugin class
jig interface --package my_package --plugin my_package::MyNode

# Output as YAML instead of JSON (default)
jig interface --package my_package --executable my_node --format yaml

jig interfaces – list all installed interfaces

List every jig node interface installed in the current workspace:

jig interfaces
jig interfaces --format yaml

Discovery

The CLI scans every prefix in AMENT_PREFIX_PATH for interface YAML files at the standard install location:

<prefix>/share/<package>/interfaces/*.yaml

When the same node appears in multiple locations, the following priority rules apply:

1. Native over vendored – an interface installed by its own package wins over a copy installed by another package.
2. Earlier prefix wins – the first match in AMENT_PREFIX_PATH order takes precedence.

Output format

Output defaults to JSON (one line). Use --format yaml for human-readable output. Both formats contain the full resolved interface definition including node metadata, parameters, publishers, subscribers, services, actions, and any implicit interfaces.

{
  "node": {
    "name": "my_node",
    "package": "my_package",
    "plugin": "my_package::MyNode"
  },
  "parameters": { ... },
  "publishers": [ ... ],
  "subscribers": [ ... ],
  "services": [ ... ]
}