ros2cli.helpers module

ros2cli.helpers.before_invocation(func, hook)

Invoke a hook before every func invocation.

hook may take no arguments or take the func and arbitrary positional and keyword arguments.

ros2cli.helpers.bind(func, *args, **kwargs)

Bind a function with a set of arguments.

A functools.partial equivalent that is actually a function.

ros2cli.helpers.check_discovery_configuration()

Check for invalid ROS discovery configuration and print warning if needed.

Warns when ROS_AUTOMATIC_DISCOVERY_RANGE=OFF is set without ROS_STATIC_PEERS, which results in no discovery mechanism being available.

The warning is only shown once per process to avoid duplicate warnings when multiple nodes are created.

ros2cli.helpers.collect_stdin()
ros2cli.helpers.get_rmw_additional_env(rmw_implementation: str) → Dict[str, str]

Get a dictionary of additional environment variables based on rmw.

ros2cli.helpers.get_ros_domain_id()
ros2cli.helpers.interactive_select(items: list[str], prompt: str = 'Select an item:') → str | None

Launch interactive fuzzy search using fzf to select from a list of items.

Parameters:

  • items – List of items to select from

  • prompt – Prompt message to display in fzf

Returns:

Selected item or None if user cancelled or fzf not available

ros2cli.helpers.pretty_print_call(func, *args, **kwargs)

Print a function invocation.

See before_invocation for usage as a hook.

ros2cli.helpers.unsigned_int(string)
ros2cli.helpers.wait_for(predicate, timeout, period=0.1)

Wait for a predicate to evaluate to True.

Parameters:

  • timeout – duration, in seconds, to wait for the predicate to evaluate to True. Non-positive durations will result in an indefinite wait.

  • period – predicate evaluation period, in seconds.

Returns:

predicate result