allow service creation without handling the request header

Author: marcbone

examples/minimal_client_service/src/minimal_service.rs

@@ -3,7 +3,6 @@ use std::env;
 use anyhow::{Error, Result};
 
 fn handle_service(
-    _request_header: &rclrs::rmw_request_id_t,
     request: example_interfaces::srv::AddTwoInts_Request,
 ) -> example_interfaces::srv::AddTwoInts_Response {
     println!("request: {} + {}", request.a, request.b);
@@ -17,8 +16,8 @@ fn main() -> Result<(), Error> {
 
     let node = rclrs::create_node(&context, "minimal_service")?;
 
-    let _server = node
-        .create_service::<example_interfaces::srv::AddTwoInts>("add_two_ints", handle_service)?;
+    let _server =
+        node.create_service::<example_interfaces::srv::AddTwoInts>("add_two_ints", handle_service)?;
 
     println!("Starting server");
     rclrs::spin(node).map_err(|err| err.into())

rclrs/src/node.rs

@@ -264,6 +264,25 @@ impl Node {
     /// [1]: crate::Service
     // TODO: make service's lifetime depend on node's lifetime
     pub fn create_service<T>(
+        &self,
+        topic: &str,
+        mut callback: impl FnMut(T::Request) -> T::Response + 'static + Send,
+    ) -> Result<Arc<Service<T>>, RclrsError>
+    where
+        T: rosidl_runtime_rs::Service,
+    {
+        let callback =
+            move |_request_header: &rmw_request_id_t, request: T::Request| callback(request);
+        self.create_service_with_header(topic, callback)
+    }
+
+    /// Creates a [`Service`][1]. Same as [`create_service`][2] but the callback
+    /// also has access to the ID of the service request.
+    ///
+    /// [1]: crate::Service
+    /// [2]: Self::create_service
+    // TODO: make service's lifetime depend on node's lifetime
+    pub fn create_service_with_header<T>(
         &self,
         topic: &str,
         callback: impl FnMut(&rmw_request_id_t, T::Request) -> T::Response + 'static + Send,

rclrs/src/service.rs

@@ -51,11 +51,13 @@ type ServiceCallback<Request, Response> =
 
 /// Main class responsible for responding to requests sent by ROS clients.
 ///
-/// The only available way to instantiate services is via [`Node::create_service()`][1], this is to
-/// ensure that [`Node`][2]s can track all the services that have been created.
+/// The only available way to instantiate services is via [`Node::create_service()`][1] and
+/// [`Node::create_service_with_header()`][2], this is to
+/// ensure that [`Node`][3]s can track all the services that have been created.
 ///
 /// [1]: crate::Node::create_service
-/// [2]: crate::Node
+/// [2]: crate::Node::create_service_with_header
+/// [3]: crate::Node
 pub struct Service<T>
 where
     T: rosidl_runtime_rs::Service,