use crate::util::CollectToResult;
use either::Either;
use proc_macro2::{Ident, TokenStream};
use quote::quote;
use std::iter;
use syn::{
parse::{Parse, ParseStream},
punctuated::Punctuated,
spanned::Spanned,
DeriveInput, Error, Generics, Path, Result, Token
};
struct MimeList(Punctuated<Path, Token![,]>);
impl Parse for MimeList {
fn parse(input: ParseStream<'_>) -> Result<Self> {
let list = Punctuated::parse_separated_nonempty(input)?;
Ok(Self(list))
}
}
#[cfg(not(feature = "openapi"))]
fn impl_openapi_type(_ident: &Ident, _generics: &Generics) -> TokenStream {
quote!()
}
#[cfg(feature = "openapi")]
fn impl_openapi_type(ident: &Ident, generics: &Generics) -> TokenStream {
quote! {
impl #generics ::gotham_restful::private::OpenapiType for #ident #generics {
fn visit_type<V>(visitor: &mut V)
where
V: ::gotham_restful::private::Visitor
{
visitor.visit_binary();
}
}
}
}
pub fn expand_request_body(input: DeriveInput) -> Result<TokenStream> {
let ident = input.ident;
let generics = input.generics;
let types = input
.attrs
.into_iter()
.filter(|attr| {
attr.path
.segments
.iter()
.last()
.map(|segment| segment.ident.to_string())
== Some("supported_types".to_string())
})
.flat_map(|attr| {
let span = attr.span();
attr.parse_args::<MimeList>()
.map(|list| Either::Left(list.0.into_iter().map(Ok)))
.unwrap_or_else(|mut err| {
err.combine(Error::new(
span,
"Hint: Types list should look like #[supported_types(TEXT_PLAIN, APPLICATION_JSON)]"
));
Either::Right(iter::once(Err(err)))
})
})
.collect_to_result()?;
let types = match types {
ref types if types.is_empty() => quote!(None),
types => quote!(Some(vec![#(#types),*]))
};
let impl_openapi_type = impl_openapi_type(&ident, &generics);
Ok(quote! {
impl #generics ::gotham_restful::RequestBody for #ident #generics
where #ident #generics : ::gotham_restful::FromBody
{
fn supported_types() -> ::core::option::Option<::std::vec::Vec<::gotham_restful::gotham::mime::Mime>> {
#types
}
}
#impl_openapi_type
})
}