support seeded deser

proxy/src/auth/backend/jwt.rs

@@ -1,5 +1,6 @@
 use std::{
     future::Future,
+    marker::PhantomData,
     sync::Arc,
     time::{Duration, SystemTime},
 };
@@ -148,6 +149,7 @@ impl JwkCacheEntryLock {
                 Ok(r) => {
                     let resp: http::Response<reqwest::Body> = r.into();
                     match parse_json_body_with_limit::<jose_jwk::JwkSet, _>(
+                        PhantomData,
                         resp.into_body(),
                         MAX_JWK_BODY_SIZE,
                     )

proxy/src/http.rs

@@ -9,7 +9,7 @@ use std::time::Duration;
 use bytes::Bytes;
 use http_body_util::BodyExt;
 use hyper1::body::Body;
-use serde::de::DeserializeOwned;
+use serde::de::DeserializeSeed;
 
 pub(crate) use reqwest::{Request, Response};
 pub(crate) use reqwest_middleware::{ClientWithMiddleware, Error};
@@ -122,7 +122,8 @@ pub(crate) enum ReadPayloadError<E> {
     LengthExceeded(usize),
 }
 
-pub(crate) async fn parse_json_body_with_limit<D: DeserializeOwned, E>(
+pub(crate) async fn parse_json_body_with_limit<D, E>(
+    seed: impl for<'de> DeserializeSeed<'de, Value = D>,
     mut b: impl Body<Data = Bytes, Error = E> + Unpin,
     limit: usize,
 ) -> Result<D, ReadPayloadError<E>> {
@@ -151,7 +152,7 @@ pub(crate) async fn parse_json_body_with_limit<D: DeserializeOwned, E>(
         }
     }
 
-    Ok(serde_json::from_slice::<D>(&bytes)?)
+    Ok(seed.deserialize(&mut serde_json::Deserializer::from_slice(&bytes))?)
 }
 
 #[cfg(test)]

proxy/src/serverless/sql_over_http.rs

@@ -1,3 +1,4 @@
+use std::marker::PhantomData;
 use std::pin::pin;
 use std::sync::Arc;
 
@@ -605,6 +606,7 @@ async fn handle_db_inner(
 
     let fetch_and_process_request = Box::pin(async {
         let payload = parse_json_body_with_limit(
+            PhantomData,
             request.into_body(),
             config.http_config.max_request_size_bytes as usize,
         )