nros::Service< S > Class Template Reference

#include <service.hpp>

Public Types
using	RequestType = typename S::Request
using	ResponseType = typename S::Response
using	TypedServiceFn = void(*)(const RequestType &request, ResponseType &response)
using	TypedServiceFnWithCtx = void(*)(const RequestType &request, ResponseType &response, void *ctx)

Public Member Functions
size_t	handle_id () const
bool	is_valid () const
	Check if the service is initialized and valid.
Service &	operator= (Service &&other)
Result	send_reply (int64_t seq_id, const ResponseType &resp)
Result	send_response (int64_t seq_id, const ResponseType &resp)
	Service ()
	Service (Service &&other)
Result	take_request (RequestType &req, int64_t &seq_id)
Result	try_recv_request (RequestType &req, int64_t &seq_id)
template<size_t Cap>
Result	try_recv_request_sized (RequestType &req, int64_t &seq_id)
	~Service ()

Friends
class	Node

Detailed Description

template<typename S>
class nros::Service< S >

Typed service server for a ROS 2 service.

Mirrors rclcpp::Service<S>. The service type S must provide nested Request and Response types with TYPE_NAME, TYPE_HASH, SERIALIZED_SIZE_MAX, ffi_serialize(), and ffi_deserialize().

Usage:

nros::Service<example_interfaces::srv::AddTwoInts> srv;
NROS_TRY(node.create_service(srv, "/add_two_ints"));
typename decltype(srv)::RequestType req;
int64_t seq;
if (srv.take_request(req, seq)) {
    typename decltype(srv)::ResponseType resp;
    resp.sum = req.a + req.b;
    srv.send_response(seq, resp);
}

Member Typedef Documentation

RequestType

template<typename S >

using nros::Service< S >::RequestType = typename S::Request

ResponseType

template<typename S >

using nros::Service< S >::ResponseType = typename S::Response

TypedServiceFn

template<typename S >

using nros::Service< S >::TypedServiceFn = void (*)(const RequestType& request, ResponseType& response)

Phase 189.M3.3.e — typed request-handler signatures for the callback-style service (rclcpp dispatch model). The handler fills response from request; the executor sends the reply during spin.

TypedServiceFnWithCtx

template<typename S >

using nros::Service< S >::TypedServiceFnWithCtx = void (*)(const RequestType& request, ResponseType& response, void* ctx)

Constructor & Destructor Documentation

~Service()

template<typename S >

nros::Service< S >::~Service ( )

inline

Destructor — releases service server resources.

Poll-style services own an RmwServiceServer in storage_ and free it here. Callback-style services (Phase 189.M3.3.e) are owned by the executor arena (freed when the executor drops), so the dtor must NOT touch storage_ for them.

Service() [1/2]

template<typename S >

nros::Service< S >::Service ( Service< S > &&  other )

inline

Service() [2/2]

template<typename S >

nros::Service< S >::Service ( )

inline

Default constructor — creates an uninitialized service server. Use Node::create_service() to initialize.

Member Function Documentation

handle_id()

template<typename S >

size_t nros::Service< S >::handle_id ( ) const

inline

Executor handle for the callback-style service (Phase 189.M3.3.e); SIZE_MAX for poll-style / uninitialized.

is_valid()

template<typename S >

bool nros::Service< S >::is_valid ( ) const

inline

Check if the service is initialized and valid.

operator=()

template<typename S >

Service & nros::Service< S >::operator= ( Service< S > &&  other )

inline

send_reply()

template<typename S >

Result nros::Service< S >::send_reply ( int64_t  seq_id, const ResponseType &  resp  )

inline

Deprecated:

Use send_response().

Phase-379 W5: rcl, rclcpp and rclrs all say send_response, and our own C already used that word. Kept as a forwarder so an out-of-tree node on the old spelling still compiles and is told what to move to.

send_response()

template<typename S >

Result nros::Service< S >::send_response ( int64_t  seq_id, const ResponseType &  resp  )

inline

Send a typed reply to a previously received request.

Parameters

seq_id	Sequence number from take_request().
resp	Response to send.

Returns

Result indicating success or failure.

take_request()

template<typename S >

Result nros::Service< S >::take_request ( RequestType &  req, int64_t &  seq_id  )

inline

Try to receive a typed request (non-blocking).

Parameters

req	Output request struct (filled on success).
seq_id	Output sequence number for reply matching.

Returns

Result::success() if a request was received and deserialized; ErrorCode::TryAgain if no data is available; ErrorCode::NotInitialized or the FFI error code otherwise; ErrorCode::Error if deserialization failed.

try_recv_request()

template<typename S >

Result nros::Service< S >::try_recv_request ( RequestType &  req, int64_t &  seq_id  )

inline

Deprecated:

Use take_request(RequestType&, int64_t&).

phase-379 W6 decision 1 (2026-09-03): take -> take. rcl (rcl_take_request), rclcpp (Service::take_request) and our own RMW vtable (take_request) already said take; only this layer said take. Header-only forwarder, no ABI cost. Scheduled for removal.

try_recv_request_sized()

template<typename S >

template<size_t Cap>

Result nros::Service< S >::try_recv_request_sized ( RequestType &  req, int64_t &  seq_id  )

inline

take_request with the receive buffer sized by the CALLER.

This IS a receive buffer — issue 0964's survey listed the service request under "transmit", which is true of Client<S>'s request and false here: the server deserializes out of it, so an under-estimate truncates. See Subscription::take_sized.

Friends And Related Symbol Documentation

Node

template<typename S >

friend class Node

friend

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The documentation for this class was generated from the following files:

• include/nros/node.hpp
• include/nros/service.hpp