Module action 

ROS 2 Action types

Actions provide asynchronous goal-based communication with feedback. An action client sends a goal to an action server, which executes the goal and provides feedback during execution and a result upon completion.

Action Communication Pattern

Actions use 5 underlying communication channels:

• send_goal service: Submit a new goal
• cancel_goal service: Request cancellation
• get_result service: Retrieve final result
• feedback topic: Progress updates during execution
• status topic: Goal state transitions

Example

use nros_core::{RosAction, GoalStatusCode};

// Define an action type
struct Fibonacci;

impl RosAction for Fibonacci {
    type Goal = FibonacciGoal;
    type Result = FibonacciResult;
    type Feedback = FibonacciFeedback;

    const ACTION_NAME: &'static str = "example_interfaces::action::dds_::Fibonacci_";
    const ACTION_HASH: &'static str = "...";
}

Structs

GoalInfo

Information about a goal

GoalStatusStamped

Goal status with associated goal info

GoalUuid

Unique identifier for a goal – rclrs’s GoalUuid (phase-515 R8).

Enums

CancelResponse

Per-goal cancel decision returned from a server’s cancel callback.

CancelResponseCode

action_msgs/srv/CancelGoal RPC return codes.

GoalResponse

Goal accept/reject response codes

GoalStatusCode

Goal status states – rclrs’s GoalStatusCode (phase-515 R8).

Traits

RosAction

Trait for ROS 2 action types

Type Aliases

CancelReturnCodeDeprecated

The pre-phase-515 name of CancelResponseCode.

GoalIdDeprecated

The pre-phase-515 name of GoalUuid.

GoalStatusDeprecated

The pre-phase-515 name of GoalStatusCode.