feat: add utoipa

Cargo.toml

@@ -12,9 +12,11 @@ version = "0.0.1"
 [workspace.dependencies]
 breach = { path = "./packages/breach", version = "0.0.1" }
 breach-macros = { path = "./packages/breach-macros", version = "0.0.1" }
+http = "1.4.0"
 serde = "1.0.228"
 serde_json = "1.0.149"
 tokio = "1.49.0"
+utoipa = "5.4.0"
 
 [workspace.lints.rust]
 unsafe_code = "deny"

examples/axum/Cargo.toml

@@ -12,10 +12,10 @@ version.workspace = true
 [dependencies]
 anyhow = "1.0.101"
 axum = "0.8.8"
-breach.workspace = true
+breach = { workspace = true, features = ["utoipa"] }
 serde = { workspace = true, features = ["derive"] }
 tokio = { workspace = true, features = ["macros", "rt-multi-thread"] }
-utoipa = { version = "5.4.0", features = ["axum_extras", "uuid"] }
+utoipa = { workspace = true, features = ["axum_extras", "uuid"] }
 utoipa-axum = "0.2.0"
 utoipa-scalar = { version = "0.3.0", features = ["axum"] }
 uuid = { version = "1.20.0", features = ["serde", "v7"] }

examples/axum/src/error.rs

@@ -1,9 +1,10 @@
 use breach::HttpError;
 use serde::Serialize;
+use utoipa::ToSchema;
 use uuid::Uuid;
 
-#[derive(HttpError, Serialize)]
-#[http(status = NOT_FOUND)]
+#[derive(HttpError, Serialize, ToSchema)]
+#[http(status = NOT_FOUND, utoipa)]
 #[serde(rename_all = "camelCase")]
 pub struct NotFoundError {
     id: Uuid,

examples/axum/src/user/errors.rs

@@ -1,9 +1,10 @@
 use breach::HttpError;
 use serde::Serialize;
+use utoipa::ToSchema;
 
 use crate::error::NotFoundError;
 
-#[derive(Serialize)]
+#[derive(Serialize, ToSchema)]
 #[serde(
     tag = "code",
     rename_all = "camelCase",
@@ -14,6 +15,7 @@ pub enum UserValidationError {
 }
 
 #[derive(HttpError, Serialize)]
+#[http(utoipa)]
 #[serde(
     tag = "code",
     rename_all = "camelCase",
@@ -34,6 +36,7 @@ impl From<UserValidationError> for CreateUserError {
 }
 
 #[derive(HttpError, Serialize)]
+#[http(utoipa)]
 #[serde(
     tag = "code",
     rename_all = "camelCase",
@@ -47,6 +50,7 @@ pub enum GetUserByIdError {
 }
 
 #[derive(HttpError, Serialize)]
+#[http(utoipa)]
 #[serde(
     tag = "code",
     rename_all = "camelCase",
@@ -67,6 +71,7 @@ impl From<UserValidationError> for UpdateUserError {
 }
 
 #[derive(HttpError, Serialize)]
+#[http(utoipa)]
 #[serde(
     tag = "code",
     rename_all = "camelCase",

examples/axum/src/user/routes.rs

@@ -27,7 +27,7 @@ impl UserRoutes {
 }
 
 #[derive(HttpError, Serialize)]
-#[http(axum)]
+#[http(axum, utoipa)]
 pub enum CreateUserRouteError {
     CreateUser(CreateUserError),
 }
@@ -47,7 +47,8 @@ impl From<CreateUserError> for CreateUserRouteError {
     tags = ["User"],
     request_body = CreateUser,
     responses(
-        (status = CREATED, description = "The user has been created.", body = User)
+        (status = CREATED, description = "The user has been created.", body = User),
+        CreateUserRouteError,
     )
 )]
 async fn create_user(
@@ -60,7 +61,7 @@ async fn create_user(
 }
 
 #[derive(HttpError, Serialize)]
-#[http(axum)]
+#[http(axum, utoipa)]
 pub enum GetUserRouteError {
     GetUserById(GetUserByIdError),
 }
@@ -80,7 +81,8 @@ impl From<GetUserByIdError> for GetUserRouteError {
     tags = ["User"],
     params(UserPathParams),
     responses(
-        (status = OK, description = "The user.", body = User)
+        (status = OK, description = "The user.", body = User),
+        GetUserRouteError,
     )
 )]
 async fn user(
@@ -93,7 +95,7 @@ async fn user(
 }
 
 #[derive(HttpError, Serialize)]
-#[http(axum)]
+#[http(axum, utoipa)]
 pub enum UpdateUserRouteError {
     GetUserById(GetUserByIdError),
 
@@ -122,7 +124,8 @@ impl From<UpdateUserError> for UpdateUserRouteError {
     params(UserPathParams),
     request_body = UpdateUser,
     responses(
-        (status = OK, description = "The user has been updated.", body = User)
+        (status = OK, description = "The user has been updated.", body = User),
+        UpdateUserRouteError,
     )
 )]
 async fn update_user(
@@ -138,7 +141,7 @@ async fn update_user(
 }
 
 #[derive(HttpError, Serialize)]
-#[http(axum)]
+#[http(axum, utoipa)]
 pub enum DeleteUserRouteError {
     GetUserById(GetUserByIdError),
 
@@ -166,7 +169,8 @@ impl From<DeleteUserError> for DeleteUserRouteError {
     tags = ["User"],
     params(UserPathParams),
     responses(
-        (status = NO_CONTENT, description = "The user has been deleted.")
+        (status = NO_CONTENT, description = "The user has been deleted."),
+        DeleteUserRouteError,
     )
 )]
 async fn delete_user(

examples/basic/src/main.rs

@@ -3,6 +3,12 @@ use breach::{HttpError, http::StatusCode};
 use serde::Serialize;
 use serde_json::json;
 
+#[derive(Serialize)]
+#[serde(rename_all = "camelCase")]
+struct ForbiddenError {
+    id: String,
+}
+
 #[derive(HttpError, Serialize)]
 #[http(status = NOT_FOUND)]
 #[serde(rename_all = "camelCase")]
@@ -18,9 +24,7 @@ struct NotFoundError {
 )]
 enum GetUserByIdError {
     #[http(status = FORBIDDEN)]
-    Forbidden {
-        id: String,
-    },
+    Forbidden(ForbiddenError),
 
     NotFound(NotFoundError),
 
@@ -37,15 +41,17 @@ enum GetUserByIdError {
 enum UpdateUserError {
     GetUserById(GetUserByIdError),
 
-    #[http(status = UNPROCESSABLE_CONTENT)]
+    #[http(status = UNPROCESSABLE_ENTITY)]
     Validation,
 
     #[http(status = INTERNAL_SERVER_ERROR)]
     Internal(#[serde(skip)] anyhow::Error),
 }
 
 fn main() {
-    let error = UpdateUserError::GetUserById(GetUserByIdError::Forbidden { id: "1".to_owned() });
+    let error = UpdateUserError::GetUserById(GetUserByIdError::Forbidden(ForbiddenError {
+        id: "1".to_owned(),
+    }));
     assert_eq!(StatusCode::FORBIDDEN, error.status());
     assert_eq!(
         json!({

packages/breach-macros/Cargo.toml

@@ -20,6 +20,7 @@ serde = []
 utoipa = []
 
 [dependencies]
+http.workspace = true
 proc-macro2 = "1.0.103"
 quote = "1.0.42"
 syn = "2.0.110"

packages/breach-macros/src/http.rs

@@ -42,17 +42,30 @@ impl<'a> ToTokens for HttpError<'a> {
             }
         });
 
-        if let Some(attribute) = self.data.attribute()
-            && attribute.axum
-        {
-            tokens.append_all(quote! {
-                #[automatically_derived]
-                impl #impl_generics ::axum::response::IntoResponse for #ident #type_generics #where_clause {
-                    fn into_response(self) -> ::axum::response::Response {
-                        (self.status(), Json(self)).into_response()
+        if let Some(attribute) = self.data.attribute() {
+            if attribute.axum {
+                tokens.append_all(quote! {
+                    #[automatically_derived]
+                    impl #impl_generics ::axum::response::IntoResponse for #ident #type_generics #where_clause {
+                        fn into_response(self) -> ::axum::response::Response {
+                            (self.status(), Json(self)).into_response()
+                        }
                     }
-                }
-            });
+                });
+            }
+
+            if attribute.utoipa {
+                let responses = self.data.responses();
+
+                tokens.append_all(quote! {
+                    #[automatically_derived]
+                    impl #impl_generics ::utoipa::IntoResponses for #ident #type_generics #where_clause {
+                        fn responses() -> ::std::collections::BTreeMap<String, ::utoipa::openapi::RefOr<::utoipa::openapi::response::Response>> {
+                            #responses
+                        }
+                    }
+                });
+            }
         }
     }
 }

packages/breach-macros/src/http/attribute.rs

@@ -1,10 +1,13 @@
 use proc_macro2::TokenStream;
 use quote::quote;
-use syn::{Attribute, Error, Ident, Result, spanned::Spanned};
+use syn::{Attribute, Error, Result, spanned::Spanned};
+
+use crate::status::Status;
 
 pub struct HttpErrorAttribute {
-    status: Option<Ident>,
+    pub status: Option<Status>,
     pub axum: bool,
+    pub utoipa: bool,
 }
 
 impl<'a> HttpErrorAttribute {
@@ -32,6 +35,7 @@ impl<'a> HttpErrorAttribute {
     pub fn parse(attribute: &'a Attribute) -> Result<Self> {
         let mut status = None;
         let mut axum = false;
+        let mut utoipa = false;
 
         attribute.parse_nested_meta(|meta| {
             if meta.path.is_ident("status") {
@@ -41,21 +45,60 @@ impl<'a> HttpErrorAttribute {
             } else if meta.path.is_ident("axum") {
                 axum = true;
 
+                Ok(())
+            } else if meta.path.is_ident("utoipa") {
+                utoipa = true;
+
                 Ok(())
             } else {
                 Err(meta.error("unknown parameter"))
             }
         })?;
 
-        Ok(Self { status, axum })
+        Ok(Self {
+            status,
+            axum,
+            utoipa,
+        })
     }
 
     pub fn status(&self) -> TokenStream {
         if let Some(status) = &self.status {
-            if status == "UNPROCESSABLE_CONTENT" {
-                quote!(::breach::http::StatusCode::UNPROCESSABLE_ENTITY)
-            } else {
-                quote!(::breach::http::StatusCode::#status)
+            let status = status.as_ident();
+
+            quote!(::breach::http::StatusCode::#status)
+        } else {
+            quote!(compile_error!("missing `#[http(status = ..)]` attribute"))
+        }
+    }
+
+    pub fn responses(&self, r#type: Option<TokenStream>) -> TokenStream {
+        if let Some(status) = &self.status {
+            let code = status.code.as_str();
+
+            let content = r#type.map(|r#type| {
+                // TODO: Attempt to infer content type from schema?
+                quote! {
+                    .content(
+                        "application/json",
+                        ::utoipa::openapi::content::ContentBuilder::new()
+                            .schema(Some(<#r#type as ::utoipa::PartialSchema>::schema()))
+                            .build()
+                    )
+                }
+            });
+
+            quote! {
+                ::std::collections::BTreeMap::from_iter([
+                    (
+                        #code.to_owned(),
+                        ::utoipa::openapi::RefOr::T(
+                            ::utoipa::openapi::response::ResponseBuilder::new()
+                                #content
+                                .build()
+                        ),
+                    ),
+                ])
             }
         } else {
             quote!(compile_error!("missing `#[http(status = ..)]` attribute"))

packages/breach-macros/src/http/data.rs

@@ -36,4 +36,12 @@ impl<'a> HttpErrorData<'a> {
             HttpErrorData::Union(r#union) => r#union.status(),
         }
     }
+
+    pub fn responses(&self) -> TokenStream {
+        match self {
+            HttpErrorData::Struct(r#struct) => r#struct.responses(),
+            HttpErrorData::Enum(r#enum) => r#enum.responses(),
+            HttpErrorData::Union(r#union) => r#union.responses(),
+        }
+    }
 }