chore: add custom json extractor with problem details rejection response

src/extractors.rs

@@ -0,0 +1,49 @@
+use std::error::Error;
+
+use axum::{
+    async_trait,
+    extract::{rejection::JsonRejection, FromRequest, Request},
+    response::IntoResponse,
+};
+use problemdetails::Problem;
+use serde::Serialize;
+
+pub struct Json<T>(pub T);
+
+#[async_trait]
+impl<S, T> FromRequest<S> for Json<T>
+where
+    axum::Json<T>: FromRequest<S, Rejection = JsonRejection>,
+    S: Send + Sync,
+{
+    type Rejection = Problem;
+    async fn from_request(req: Request, state: &S) -> Result<Self, Self::Rejection> {
+        match axum::Json::<T>::from_request(req, state).await {
+            Ok(value) => Ok(Self(value.0)),
+            Err(rejection) => Err(match rejection {
+                JsonRejection::MissingJsonContentType(err) => problemdetails::new(err.status())
+                    .with_title("Invalid Content-Type header.")
+                    .with_detail("Content-Type header either missing or invalid - please add `Content-Type: application/json` header."),
+                JsonRejection::JsonSyntaxError(err) => problemdetails::new(err.status())
+                    .with_title("Invalid json syntax.")
+                    .with_detail("Provided json body contains a syntax error - please fix it.")
+                    .with_value("error", err.source().map(|e| e.to_string()).unwrap_or_default()),
+                JsonRejection::JsonDataError(err) => problemdetails::new(err.status())
+                    .with_title("Invalid json data.")
+                    .with_detail("Provided json body contains invalid or missing data - please fix it.")
+                    .with_value("error", err.source().map(|e| e.to_string()).unwrap_or_default()),
+                JsonRejection::BytesRejection(err) => problemdetails::new(err.status()),
+                _ => problemdetails::new(rejection.status()),
+            }),
+        }
+    }
+}
+
+impl<T> IntoResponse for Json<T>
+where
+    T: Serialize,
+{
+    fn into_response(self) -> axum::response::Response {
+        axum::Json(self.0).into_response()
+    }
+}

src/lib.rs

@@ -1,4 +1,5 @@
 pub mod domain;
+pub mod extractors;
 pub mod handlers;
 pub mod settings;
 pub mod startup;