Struct CallbackCtx 

pub struct CallbackCtx<'a> { /* private fields */ }

Implementations

impl<'a> CallbackCtx<'a>

pub fn new(payload: &'a [u8], publishers: &'a dyn PublisherResolver) -> Self

Build a callback context with no reply sink (timer / subscription). payload is the entity’s raw CDR (empty slice for timers).

pub fn with_reply( payload: &'a [u8], publishers: &'a dyn PublisherResolver, reply_buf: &'a mut [u8], reply_written: &'a mut usize, ) -> Self

Build a callback context with a reply sink (service / action-result; W.5.3). The body fills reply_buf via reply; the generated trampoline reads *reply_written back as the response length.

pub fn with_goal_decision( payload: &'a [u8], publishers: &'a dyn PublisherResolver, out: &'a mut GoalResponse, ) -> Self

Build a context for an action goal callback (W.5.3): the body decides accept/reject via set_goal_response; the generated trampoline returns *out. payload is the goal CDR.

pub fn with_cancel_decision( payload: &'a [u8], publishers: &'a dyn PublisherResolver, out: &'a mut CancelResponse, ) -> Self

Build a context for an action cancel callback (W.5.3): the body decides accept/reject via set_cancel_response.

pub fn set_goal_response(&mut self, response: GoalResponse) -> NodeResult<()>

Set the action goal-callback’s accept/reject decision (W.5.3). Err when the callback is not a goal decision.

pub fn set_cancel_response( &mut self, response: CancelResponse, ) -> NodeResult<()>

Set the action cancel-callback’s accept/reject decision (W.5.3). Err when the callback is not a cancel decision.

Issue 0796 — CancelResponse here is the PER-GOAL decision (Reject / Accept), the twin of GoalResponse and the same two values C’s rclc_cancel_response_t and C++’s nros::CancelResponse carry. It used to be the action_msgs/srv/CancelGoal RPC return code (now nros_core::CancelResponseCode), so answering “cancel this goal” was spelled CancelResponse::Ok — a whole-request status code used to decide one goal.

pub fn reply_raw(&mut self, data: &[u8]) -> NodeResult<()>

Write the service / action reply as raw CDR bytes (W.5.3). Err when the callback has no reply sink (timer / subscription) or the reply exceeds the lent buffer.

pub fn reply<M: RosMessage, const N: usize>( &mut self, msg: &M, ) -> NodeResult<()>

Serialize msg and write it as the service / action reply (W.5.3).

pub fn payload(&self) -> &[u8]

Raw CDR payload of the triggering message / request. Empty for timers.

pub fn timer_info(&self) -> Option<&TimerCallInfo>

Issue 2038 — the call info of the timer activation being dispatched: when it was due (expected_call_time) and when the executor ran it (actual_call_time), in nanoseconds on the timer’s clock. Some only in a declared TIMER’s callback; None for subscriptions, services and actions. The same two numbers Node::create_timer_with_info and C++’s rclcpp::TimerInfo receive — one producer, the executor’s dispatcher.

pub fn reset_timer(&self, timer: EntityId<'_>) -> NodeResult<()>

Issue 2075 — reset the declared timer timer: rclcpp’s TimerBase::reset(). Starts a timer declared with autostart = false (DeclarativeNode::create_timer_for_callback_name_with_autostart), and restarts a running one on a fresh period.

The request is applied at this component’s next tick, in the same spin, once the callbacks of the pass have run: a callback does not hold the executor. timer is the timer’s entity id, which for the ..._for_callback_name verbs is the callback name. Answers NodeDeclError::UnknownTimer when this component has no controllable timer by that id (see EntityBounds::timers).

ctx.reset_timer(nros::EntityId::new("on_tick"))?;

pub fn cancel_timer(&self, timer: EntityId<'_>) -> NodeResult<()>

Issue 2075 — cancel the declared timer timer: rclcpp’s TimerBase::cancel(). It stops firing until reset_timer. Applied at the next tick, like reset_timer.

pub fn message<M: RosMessage>(&self) -> NodeResult<M>

Deserialize the triggering payload as M (subscription / service-request bodies). Err if the payload is malformed for M.

pub fn publish_to_topic<M: RosMessage, const N: usize>( &self, topic: &str, msg: &M, ) -> NodeResult<()>

Serialize msg and publish through the entity synthesized from topic.

This pairs with DeclarativeNode::create_publisher_for_topic, allowing simple callback bodies to use the ROS topic literal instead of restating an unrelated stable entity ID.