This library provides the infrastructure for derive macros to extract RDF metadata from attributes and generate serialization/deserialization code.

• Defines RDF attributes for Rust types
• Parses RDF attributes to a structured RDF metadata representation metadata::RdfType
• Provides a trait TokenGenerator that authors can implement in a derive macro to generate code based on the metadata from metadata::RdfType

The linked-data-sparql repository has an implementation.

1. Annotate a type:

   #[ld(type = "http://schema.org/Person")] #[ld(prefix("schema" = "http://schema.org/"))] struct Person { #[ld("schema:name")] name: String, }

2. To generate code:

   use linked_data_core::{ PredicatePath, RdfEnum, RdfField, RdfStruct, RdfType, RdfVariant, TokenGenerator, }; use proc_macro_error::proc_macro_error; use proc_macro2::TokenStream; use quote::ToTokens; use syn::DeriveInput; #[proc_macro_derive(MyDerive, attributes(ld))] pub fn derive_my_trait( item: proc_macro::TokenStream, ) -> proc_macro::TokenStream { let raw_input = syn::parse_macro_input!(item as DeriveInput); let linked_data_type: RdfType<MyGenerator> = RdfType::from_derive(raw_input); let mut output = TokenStream::new(); linked_data_type.to_tokens(&mut output); output.into() } struct MyGenerator; impl TokenGenerator for MyGenerator { fn generate_struct_tokens(rdf_struct: &RdfStruct<Self>, tokens: &mut TokenStream) { // Use rdf_struct metadata to generate serialization code let type_iri = rdf_struct.type_iri(); let fields = &rdf_struct.fields; // Generate your custom code... } fn generate_enum_tokens(rdf_enum: &RdfEnum<Self>, tokens: &mut TokenStream) { // Handle enum types let variants = &rdf_enum.variants; // Generate your custom code... } }

Type-Level Attributes

#[ld(type = "http://schema.org/Person")] // RDF type for instances #[ld(prefix("schema" = "http://schema.org/"))] // Define prefix mappings

Field Attributes

#[ld("http://schema.org/name")] // RDF predicate IRI #[ld("schema:name")] // Using prefix (if defined) #[ld(id)] // Mark as subject/ID field #[ld(flatten)] // Inline nested properties #[ld(graph)] // Contains graph data #[ld(ignore)] // Exclude from RDF

#[ld("http://example.org/hasRole")] // Simple predicate