feat: add axum hook (#7)

Author: DanielleHuisman

packages/breach-macros/src/http.rs

@@ -44,10 +44,18 @@ impl<'a> ToTokens for HttpError<'a> {
 
         if let Some(attribute) = self.data.attribute() {
             if attribute.axum {
+                let hook = attribute.axum_hook.as_ref().map(|hook| {
+                    quote! {
+                        #hook(&self);
+                    }
+                });
+
                 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 {
+                            #hook;
+
                             (self.status(), ::axum::Json(self)).into_response()
                         }
                     }

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

@@ -1,17 +1,69 @@
 use proc_macro2::TokenStream;
 use quote::quote;
-use syn::{Attribute, Error, Result, Type, spanned::Spanned};
+use syn::{Attribute, Error, Expr, Result, Type, spanned::Spanned};
 
 use crate::status::Status;
 
 pub struct HttpErrorAttribute {
     pub status: Option<Status>,
+}
+
+impl<'a> HttpErrorAttribute {
+    pub fn parse_slice(input: &'a [Attribute]) -> Result<Option<Self>> {
+        let mut result = None;
+
+        for attribute in input {
+            if !attribute.meta.path().is_ident("http") {
+                continue;
+            }
+
+            if result.is_some() {
+                return Err(Error::new(
+                    attribute.span(),
+                    "only a single `http` attribute is allowed",
+                ));
+            }
+
+            result = Some(Self::parse(attribute)?);
+        }
+
+        Ok(result)
+    }
+
+    pub fn parse(attribute: &'a Attribute) -> Result<Self> {
+        let mut status = None;
+
+        attribute.parse_nested_meta(|meta| {
+            if meta.path.is_ident("status") {
+                status = Some(meta.value()?.parse()?);
+
+                Ok(())
+            } else {
+                Err(meta.error("unknown parameter"))
+            }
+        })?;
+
+        Ok(Self { status })
+    }
+
+    pub fn status(&self) -> TokenStream {
+        status(self.status.as_ref())
+    }
+
+    pub fn responses(&self, r#type: Option<TokenStream>) -> TokenStream {
+        responses(self.status.as_ref(), r#type)
+    }
+}
+
+pub struct HttpErrorDataAttribute {
+    pub status: Option<Status>,
     pub base: Option<Type>,
     pub axum: bool,
+    pub axum_hook: Option<Expr>,
     pub utoipa: bool,
 }
 
-impl<'a> HttpErrorAttribute {
+impl<'a> HttpErrorDataAttribute {
     pub fn parse_slice(input: &'a [Attribute]) -> Result<Option<Self>> {
         let mut result = None;
 
@@ -37,6 +89,7 @@ impl<'a> HttpErrorAttribute {
         let mut status = None;
         let mut base = None;
         let mut axum = false;
+        let mut axum_hook = None;
         let mut utoipa = false;
 
         attribute.parse_nested_meta(|meta| {
@@ -51,6 +104,10 @@ impl<'a> HttpErrorAttribute {
             } else if meta.path.is_ident("axum") {
                 axum = true;
 
+                Ok(())
+            } else if meta.path.is_ident("axum_hook") {
+                axum_hook = Some(meta.value()?.parse()?);
+
                 Ok(())
             } else if meta.path.is_ident("utoipa") {
                 utoipa = true;
@@ -65,50 +122,59 @@ impl<'a> HttpErrorAttribute {
             status,
             base,
             axum,
+            axum_hook,
             utoipa,
         })
     }
 
     pub fn status(&self) -> TokenStream {
-        if let Some(status) = &self.status {
-            let status = status.as_ident();
-
-            quote!(::breach::http::StatusCode::#status)
-        } else {
-            quote!(compile_error!("missing `#[http(status = ..)]` attribute"))
-        }
+        status(self.status.as_ref())
     }
 
     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()
-                    )
-                }
-            });
+        responses(self.status.as_ref(), r#type)
+    }
+}
+
+fn status(status: Option<&Status>) -> TokenStream {
+    if let Some(status) = status {
+        let status = status.as_ident();
 
+        quote!(::breach::http::StatusCode::#status)
+    } else {
+        quote!(compile_error!("missing `#[http(status = ..)]` attribute"))
+    }
+}
+
+fn responses(status: Option<&Status>, r#type: Option<TokenStream>) -> TokenStream {
+    if let Some(status) = status {
+        let code = status.code.as_str();
+
+        let content = r#type.map(|r#type| {
+            // TODO: Attempt to infer content type from schema?
             quote! {
-                ::std::collections::BTreeMap::from_iter([
-                    (
-                        #code.to_owned(),
-                        ::utoipa::openapi::RefOr::T(
-                            ::utoipa::openapi::response::ResponseBuilder::new()
-                                #content
-                                .build()
-                        ),
-                    ),
-                ])
+                .content(
+                    "application/json",
+                    ::utoipa::openapi::content::ContentBuilder::new()
+                        .schema(Some(<#r#type as ::utoipa::PartialSchema>::schema()))
+                        .build()
+                )
             }
-        } else {
-            quote!(compile_error!("missing `#[http(status = ..)]` attribute"))
+        });
+
+        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

@@ -2,7 +2,7 @@ use proc_macro2::TokenStream;
 use syn::{Data, DeriveInput, Result};
 
 use crate::http::{
-    attribute::HttpErrorAttribute, r#enum::HttpErrorEnum, r#struct::HttpErrorStruct,
+    attribute::HttpErrorDataAttribute, r#enum::HttpErrorEnum, r#struct::HttpErrorStruct,
     union::HttpErrorUnion,
 };
 
@@ -21,7 +21,7 @@ impl<'a> HttpErrorData<'a> {
         })
     }
 
-    pub fn attribute(&self) -> Option<&HttpErrorAttribute> {
+    pub fn attribute(&self) -> Option<&HttpErrorDataAttribute> {
         match self {
             HttpErrorData::Struct(r#struct) => r#struct.attribute(),
             HttpErrorData::Enum(r#enum) => r#enum.attribute(),

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

@@ -2,20 +2,20 @@ use proc_macro2::TokenStream;
 use quote::{ToTokens, quote};
 use syn::{DataEnum, DeriveInput, Error, Field, Fields, Ident, Result, Variant, spanned::Spanned};
 
-use crate::http::attribute::HttpErrorAttribute;
+use crate::http::attribute::{HttpErrorAttribute, HttpErrorDataAttribute};
 
 pub struct HttpErrorEnum<'a> {
     ident: &'a Ident,
     variants: Vec<HttpErrorEnumVariant<'a>>,
-    attribute: Option<HttpErrorAttribute>,
+    attribute: Option<HttpErrorDataAttribute>,
 }
 
 impl<'a> HttpErrorEnum<'a> {
     pub fn parse(input: &'a DeriveInput, data: &'a DataEnum) -> Result<Self> {
         let mut result = HttpErrorEnum {
             ident: &input.ident,
             variants: Vec::with_capacity(data.variants.len()),
-            attribute: HttpErrorAttribute::parse_slice(&input.attrs)?,
+            attribute: HttpErrorDataAttribute::parse_slice(&input.attrs)?,
         };
 
         for variant in &data.variants {
@@ -27,7 +27,7 @@ impl<'a> HttpErrorEnum<'a> {
         Ok(result)
     }
 
-    pub fn attribute(&self) -> Option<&HttpErrorAttribute> {
+    pub fn attribute(&self) -> Option<&HttpErrorDataAttribute> {
         self.attribute.as_ref()
     }
 

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

@@ -2,22 +2,22 @@ use proc_macro2::TokenStream;
 use quote::quote;
 use syn::{DataStruct, DeriveInput, Error, Result, spanned::Spanned};
 
-use crate::http::attribute::HttpErrorAttribute;
+use crate::http::attribute::HttpErrorDataAttribute;
 
 pub struct HttpErrorStruct {
-    attribute: HttpErrorAttribute,
+    attribute: HttpErrorDataAttribute,
 }
 
 impl<'a> HttpErrorStruct {
     pub fn parse(input: &'a DeriveInput, _data: &'a DataStruct) -> Result<Self> {
-        let Some(attribute) = HttpErrorAttribute::parse_slice(&input.attrs)? else {
+        let Some(attribute) = HttpErrorDataAttribute::parse_slice(&input.attrs)? else {
             return Err(Error::new(input.span(), "missing http attribute"));
         };
 
         Ok(HttpErrorStruct { attribute })
     }
 
-    pub fn attribute(&self) -> Option<&HttpErrorAttribute> {
+    pub fn attribute(&self) -> Option<&HttpErrorDataAttribute> {
         Some(&self.attribute)
     }
 

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

@@ -1,7 +1,7 @@
 use proc_macro2::TokenStream;
 use syn::{DataUnion, DeriveInput, Result};
 
-use crate::http::attribute::HttpErrorAttribute;
+use crate::http::attribute::HttpErrorDataAttribute;
 
 pub struct HttpErrorUnion {}
 
@@ -10,7 +10,7 @@ impl HttpErrorUnion {
         Err(syn::Error::new_spanned(input, "union is not supported"))
     }
 
-    pub fn attribute(&self) -> Option<&HttpErrorAttribute> {
+    pub fn attribute(&self) -> Option<&HttpErrorDataAttribute> {
         None
     }