into_response/
lib.rs

1use proc_macro::TokenStream;
2use quote::quote;
3use syn::{parse_macro_input, DeriveInput};
4
5/// # Examples
6///
7/// ```
8/// use into_response::IntoResponse;
9///
10/// #[derive(IntoResponse)]
11/// struct MyResponse {
12///     message: String,
13/// }
14/// ```
15#[proc_macro_derive(IntoResponse)]
16pub fn into_response_derive(input: TokenStream) -> TokenStream {
17    let input = parse_macro_input!(input as DeriveInput);
18    let name = &input.ident;
19    let generics = &input.generics;
20
21    let mut generics_with_bounds = generics.clone();
22    for type_param in &mut generics_with_bounds.type_params_mut() {
23        type_param.bounds.push(syn::parse_quote!(serde::Serialize));
24    }
25
26    let (impl_generics, ty_generics, where_clause) = generics_with_bounds.split_for_impl();
27
28    let expanded = quote! {
29        impl #impl_generics axum::response::IntoResponse for #name #ty_generics #where_clause {
30            fn into_response(self) -> axum::response::Response {
31                axum::Json(&self).into_response()
32            }
33        }
34    };
35
36    expanded.into()
37}