Draft: Derive macro for StructuredParameters

Cargo.toml

@@ -1,5 +1,6 @@
 [workspace]
 members = [
   "rclrs",
+  "rclrs_proc_macros",
 ]
 resolver = "2"

Dockerfile

@@ -9,6 +9,8 @@ RUN apt-get update && apt-get install -y \
     libclang-dev \
     tmux \
     python3-pip \
+    ros-humble-test-msgs \
+    ros-humble-example-interfaces \
     && rm -rf /var/lib/apt/lists/*
 
 # Install Rust
@@ -22,8 +24,10 @@ COPY src/ros2_rust/docker/rosidl_rust_setup.sh /
 RUN ./rosidl_rust_setup.sh
 
 RUN mkdir -p /workspace && echo "Did you forget to mount the repository into the Docker container?" > /workspace/HELLO.txt
+RUN echo -e "\nsource /opt/ros/${ROS_DISTRO}/setup.sh"
 WORKDIR /workspace
 
+
 COPY src/ros2_rust/docker/rosidl_rust_entrypoint.sh /
 ENTRYPOINT ["/rosidl_rust_entrypoint.sh"]
 CMD ["/bin/bash"]

rclrs/Cargo.toml

@@ -36,6 +36,8 @@ rosidl_runtime_rs = "0.4"
 serde = { version = "1", optional = true, features = ["derive"] }
 serde-big-array = { version = "0.5.1", optional = true }
 
+rclrs_proc_macros = {path = "../rclrs_proc_macros"}
+
 [dev-dependencies]
 # Needed for e.g. writing yaml files in tests
 tempfile = "3.3.0"

rclrs/package.xml

@@ -19,9 +19,10 @@
   <depend>builtin_interfaces</depend>
   <depend>rcl_interfaces</depend>
   <depend>rosgraph_msgs</depend>
+  <depend>rosidl_default_generators</depend>
 
-  <test_depend>test_msgs</test_depend>
-  <test_depend>example_interfaces</test_depend>
+  <depend>test_msgs</depend>
+  <depend>example_interfaces</depend>
 
   <export>
     <build_type>ament_cargo</build_type>

rclrs/src/lib.rs

@@ -223,3 +223,5 @@ pub use time::*;
 use time_source::*;
 pub use wait_set::*;
 pub use worker::*;
+
+pub use rclrs_proc_macros::StructuredParameters;

rclrs/src/parameter.rs

@@ -871,6 +871,38 @@ impl ParameterInterface {
     }
 }
 
+pub trait StructuredParameters: Sized {
+    fn declare_structured(
+        node: &crate::NodeState,
+        name: &str,
+    ) -> core::result::Result<Self, crate::DeclarationError>;
+}
+
+impl<T: crate::ParameterVariant> StructuredParameters for crate::MandatoryParameter<T> {
+    fn declare_structured(
+        node: &crate::NodeState,
+        name: &str,
+    ) -> core::result::Result<crate::MandatoryParameter<T>, crate::DeclarationError> {
+        node.declare_parameter(name).mandatory()
+    }
+}
+impl<T: crate::ParameterVariant> StructuredParameters for crate::OptionalParameter<T> {
+    fn declare_structured(
+        node: &crate::NodeState,
+        name: &str,
+    ) -> core::result::Result<crate::OptionalParameter<T>, crate::DeclarationError> {
+        node.declare_parameter(name).optional()
+    }
+}
+impl<T: crate::ParameterVariant> StructuredParameters for crate::ReadOnlyParameter<T> {
+    fn declare_structured(
+        node: &crate::NodeState,
+        name: &str,
+    ) -> core::result::Result<crate::ReadOnlyParameter<T>, crate::DeclarationError> {
+        node.declare_parameter(name).read_only()
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -1410,4 +1442,66 @@ mod tests {
             .optional()
             .unwrap();
     }
+
+    use crate as rclrs;
+    use rclrs_proc_macros::StructuredParameters;
+
+    #[derive(StructuredParameters, Debug)]
+    struct SimpleStructuredParameters {
+        _mandatory: MandatoryParameter<f64>,
+        _optional: OptionalParameter<f64>,
+        _readonly: ReadOnlyParameter<f64>,
+    }
+
+    #[test]
+    fn test_simple_structured_parameters() {
+        let args: Vec<String> = [
+            "test",
+            "--ros-args",
+            "-p",
+            "_mandatory:=1.0",
+            "-p",
+            "_optional:=1.0",
+            "-p",
+            "_readonly:=1.0",
+        ]
+        .into_iter()
+        .map(str::to_string)
+        .collect();
+
+        let context = crate::Context::new(args, InitOptions::default()).unwrap();
+        let exec = context.create_basic_executor();
+        let node = exec.create_node(NodeOptions::new("test")).unwrap();
+        let _params = SimpleStructuredParameters::declare_structured(&node, "").unwrap();
+    }
+
+    #[derive(StructuredParameters, Debug)]
+    struct NestedStructuredParameters {
+        _simple: SimpleStructuredParameters,
+        _mandatory: MandatoryParameter<Arc<str>>,
+    }
+
+    #[test]
+    fn test_nested_structured_parameters() {
+        let args: Vec<String> = [
+            "test",
+            "--ros-args",
+            "-p",
+            "nested._simple._mandatory:=1.0",
+            "-p",
+            "nested._simple._optional:=1.0",
+            "-p",
+            "nested._simple._readonly:=1.0",
+            "-p",
+            "nested._mandatory:=foo",
+        ]
+        .into_iter()
+        .map(str::to_string)
+        .collect();
+
+        let context = crate::Context::new(args, InitOptions::default()).unwrap();
+        let exec = context.create_basic_executor();
+        let node = exec.create_node(NodeOptions::new("test")).unwrap();
+        let _params = NestedStructuredParameters::declare_structured(&node, "nested").unwrap();
+    }
 }

rclrs_proc_macros/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name= "rclrs_proc_macros"
+version = "0.0.1"
+authors = ["Balthasar Schüss <[email protected]>"]
+edition = "2021"
+license = "Apache-2.0"
+description = "A rust library providing proc macros for rclrs"
+rust-version = "1.75"
+
+
+[lib]
+path = "src/lib.rs"
+proc-macro = true
+
+[dependencies]
+proc-macro2 = "1.0"
+quote = "1.0"
+syn = "2.0"

rclrs_proc_macros/src/impl.rs

@@ -0,0 +1,67 @@
+use proc_macro2::TokenStream;
+use quote::quote;
+use syn::DeriveInput;
+
+pub(crate) fn derive_struct_parameters(input: DeriveInput) -> syn::Result<TokenStream> {
+    let ident = input.ident;
+
+    let fields = match input.data {
+        syn::Data::Struct(ref s) => &s.fields,
+        _ => {
+            return syn::Result::Err(syn::Error::new_spanned(
+                ident,
+                "StrucutredParameter trait can only be derived for structs",
+            ));
+        }
+    };
+
+    let field_types: Vec<_> = fields.iter().map(|f| &f.ty).collect();
+
+    let mut args = Vec::new();
+    for f in fields {
+        let ident = f.ident.as_ref().unwrap();
+        let ident_str = syn::LitStr::new(&f.ident.as_ref().unwrap().to_string(), ident.span());
+        let field_type = match &f.ty {
+            syn::Type::Path(p) => {
+                let mut p = p.path.clone();
+                for segment in &mut p.segments {
+                    segment.arguments = syn::PathArguments::None;
+                }
+                p
+            }
+            e => {
+                return syn::Result::Err(syn::Error::new_spanned(
+                    e,
+                    "attribute can only be path type",
+                ));
+            }
+        };
+        let r = quote! {
+           #ident : #field_type::declare_structured(
+              node, &{match name {
+                "" => #ident_str.to_string(),
+                prefix => [prefix, ".", #ident_str].concat(),
+              }
+           })?,
+        };
+        args.push(r);
+    }
+
+    let result = quote!(
+      impl #ident {
+            const _ASSERT_PARAMETER: fn() = || {
+                fn assert_parameter<T: rclrs::StructuredParameters>() {}
+                #(
+                  assert_parameter::<#field_types>();
+                )*
+            };
+        }
+
+      impl rclrs::StructuredParameters for #ident {
+        fn declare_structured(node: &rclrs::NodeState, name: &str) -> core::result::Result<Self, rclrs::DeclarationError> {
+          core::result::Result::Ok(Self{ #(#args)*})
+        }
+      }
+    );
+    syn::Result::Ok(result)
+}

rclrs_proc_macros/src/lib.rs

@@ -0,0 +1,11 @@
+mod r#impl;
+use proc_macro::TokenStream;
+use syn::{parse_macro_input, DeriveInput};
+
+#[proc_macro_derive(StructuredParameters)]
+pub fn derive_struct_parameters(input: TokenStream) -> TokenStream {
+    let input = parse_macro_input!(input as DeriveInput);
+    r#impl::derive_struct_parameters(input)
+        .unwrap_or_else(|e| e.to_compile_error())
+        .into()
+}