Implement private_key_jwks client authentication

This involves a lot of things, including:
 - better VerifyingKeystore trait
 - better errors in the JOSE crate
 - getting rid of async_trait in some JOSE traits

crates/http/src/ext.rs

@@ -12,20 +12,14 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use crate::layers::{get::Get, json::Json};
+use crate::layers::json::Json;
 
 pub trait ServiceExt: Sized {
     fn json<T>(self) -> Json<Self, T>;
-
-    fn get(self) -> Get<Self>;
 }
 
 impl<S> ServiceExt for S {
     fn json<T>(self) -> Json<Self, T> {
         Json::new(self)
     }
-
-    fn get(self) -> Get<Self> {
-        Get::new(self)
-    }
 }

crates/http/src/layers/client.rs

@@ -54,14 +54,14 @@ pub type ClientResponse<B> = Response<
     DecompressionBody<BoxBody<<B as http_body::Body>::Data, <B as http_body::Body>::Error>>,
 >;
 
-impl<ReqBody, ResBody, S> Layer<S> for ClientLayer<ReqBody>
+impl<ReqBody, ResBody, S, E> Layer<S> for ClientLayer<ReqBody>
 where
-    S: Service<Request<ReqBody>, Response = Response<ResBody>> + Clone + Send + 'static,
+    S: Service<Request<ReqBody>, Response = Response<ResBody>, Error = E> + Clone + Send + 'static,
     ReqBody: http_body::Body + Default + Send + 'static,
     ResBody: http_body::Body + Sync + Send + 'static,
     ResBody::Error: std::fmt::Display + 'static,
     S::Future: Send + 'static,
-    S::Error: Into<BoxError>,
+    E: Into<BoxError>,
 {
     type Service = BoxCloneService<Request<ReqBody>, ClientResponse<ResBody>, BoxError>;
 

crates/http/src/layers/get.rs

@@ -1,66 +0,0 @@
-// Copyright 2022 The Matrix.org Foundation C.I.C.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-use http::{Request, Uri};
-use tower::{Layer, Service};
-
-pub struct Get<S> {
-    inner: S,
-}
-
-impl<S> Get<S> {
-    pub const fn new(inner: S) -> Self {
-        Self { inner }
-    }
-}
-
-impl<S> Service<Uri> for Get<S>
-where
-    S: Service<Request<http_body::Empty<()>>>,
-{
-    type Error = S::Error;
-    type Response = S::Response;
-    type Future = S::Future;
-
-    fn poll_ready(
-        &mut self,
-        cx: &mut std::task::Context<'_>,
-    ) -> std::task::Poll<Result<(), Self::Error>> {
-        self.inner.poll_ready(cx)
-    }
-
-    fn call(&mut self, req: Uri) -> Self::Future {
-        let body = http_body::Empty::new();
-        let req = Request::builder()
-            .method("GET")
-            .uri(req)
-            .body(body)
-            .unwrap();
-        self.inner.call(req)
-    }
-}
-
-#[derive(Default, Clone, Copy)]
-pub struct GetLayer;
-
-impl<S> Layer<S> for GetLayer
-where
-    S: Service<Request<http_body::Empty<()>>>,
-{
-    type Service = Get<S>;
-
-    fn layer(&self, inner: S) -> Self::Service {
-        Get::new(inner)
-    }
-}

crates/http/src/layers/json.rs

@@ -53,6 +53,7 @@ impl<S, B> Error<S, B> {
     }
 }
 
+#[derive(Clone)]
 pub struct Json<S, T> {
     inner: S,
     _t: PhantomData<T>,

crates/http/src/layers/mod.rs

@@ -13,7 +13,6 @@
 // limitations under the License.
 
 pub(crate) mod client;
-pub(crate) mod get;
 pub(crate) mod json;
 pub(crate) mod server;
 pub(crate) mod trace;

crates/http/src/layers/server.rs

@@ -29,15 +29,16 @@ pub struct ServerLayer<ReqBody> {
     _t: PhantomData<ReqBody>,
 }
 
-impl<ReqBody, ResBody, S> Layer<S> for ServerLayer<ReqBody>
+impl<ReqBody, ResBody, S, E> Layer<S> for ServerLayer<ReqBody>
 where
-    S: Service<Request<ReqBody>, Response = Response<ResBody>> + Clone + Send + 'static,
+    S: Service<Request<ReqBody>, Response = Response<ResBody>, Error = E> + Clone + Send + 'static,
     ReqBody: http_body::Body + 'static,
     ResBody: http_body::Body + Sync + Send + 'static,
     ResBody::Error: std::fmt::Display + 'static,
     S::Future: Send + 'static,
-    S::Error: Into<BoxError>,
+    E: Into<BoxError>,
 {
+    #[allow(clippy::type_complexity)]
     type Service = BoxCloneService<
         Request<ReqBody>,
         Response<CompressionBody<BoxBody<ResBody::Data, ResBody::Error>>>,