diff options
Diffstat (limited to 'jsonrpc/jsonrpc_macro/src')
-rw-r--r-- | jsonrpc/jsonrpc_macro/src/lib.rs | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/jsonrpc/jsonrpc_macro/src/lib.rs b/jsonrpc/jsonrpc_macro/src/lib.rs new file mode 100644 index 0000000..f2015d4 --- /dev/null +++ b/jsonrpc/jsonrpc_macro/src/lib.rs @@ -0,0 +1,47 @@ +use proc_macro::TokenStream; +use proc_macro2::{Ident, TokenStream as TokenStream2}; +use quote::quote; +use syn::{parse_macro_input, spanned::Spanned, ImplItem, ItemImpl, Type}; + +macro_rules! err { + ($($tt:tt)*) => { + return syn::Error::new($($tt)*).to_compile_error().into() + }; +} + +#[proc_macro_attribute] +pub fn rpc_impl(_attr: TokenStream, item: TokenStream) -> TokenStream { + let mut methods: Vec<Ident> = vec![]; + + let item2 = item.clone(); + let parsed_input = parse_macro_input!(item2 as ItemImpl); + + let self_ty = match *parsed_input.self_ty { + Type::Path(p) => p, + _ => err!( + parsed_input.span(), + "implementing the trait `RPCService` on this type is unsupported" + ), + }; + + if parsed_input.items.is_empty() { + err!(self_ty.span(), "At least one method should be implemented"); + } + + for item in parsed_input.items { + match item { + ImplItem::Method(method) => { + methods.push(method.sig.ident); + } + _ => err!(item.span(), "unexpected item"), + } + } + + let item2: TokenStream2 = item.into(); + let quoted = quote! { + karyon_jsonrpc_internal::impl_rpc_service!(#self_ty, #(#methods),*); + #item2 + }; + + quoted.into() +} |