apollo_storage: add AppState struct for axum server

crates/apollo_storage/src/storage_reader_server.rs

@@ -13,16 +13,14 @@ use crate::{StorageError, StorageReader};
 pub struct ServerConfig {
     /// The socket address to bind the server to.
     socket: SocketAddr,
-    /// Maximum number of concurrent requests the server can handle.
-    max_concurrency: usize,
     /// Whether the server is enabled.
     enable: bool,
 }
 
 impl ServerConfig {
     /// Creates a new server configuration.
-    pub fn new(socket: SocketAddr, max_concurrency: usize, enable: bool) -> Self {
-        Self { socket, max_concurrency, enable }
+    pub fn new(socket: SocketAddr, enable: bool) -> Self {
+        Self { socket, enable }
     }
 }
 
@@ -42,19 +40,39 @@ pub trait StorageReaderServerHandler<Request, Response> {
 /// A server for handling remote storage reader queries via a configurable request handler.
 pub struct StorageReaderServer<RequestHandler, Request, Response>
 where
-    RequestHandler: StorageReaderServerHandler<Request, Response>,
+    RequestHandler: StorageReaderServerHandler<Request, Response> + Clone,
     Request: Serialize + DeserializeOwned + Send + 'static,
     Response: Serialize + DeserializeOwned + Send + 'static,
+{
+    app_state: AppState<RequestHandler, Request, Response>,
+    config: ServerConfig,
+}
+
+struct AppState<RequestHandler, Request, Response>
+where
+    RequestHandler: StorageReaderServerHandler<Request, Response> + Clone,
 {
     storage_reader: StorageReader,
     request_handler: RequestHandler,
-    config: ServerConfig,
     _req_res: PhantomData<(Request, Response)>,
 }
 
+impl<RequestHandler, Request, Response> Clone for AppState<RequestHandler, Request, Response>
+where
+    RequestHandler: StorageReaderServerHandler<Request, Response> + Clone,
+{
+    fn clone(&self) -> Self {
+        Self {
+            storage_reader: self.storage_reader.clone(),
+            request_handler: self.request_handler.clone(),
+            _req_res: PhantomData,
+        }
+    }
+}
+
 impl<RequestHandler, Request, Response> StorageReaderServer<RequestHandler, Request, Response>
 where
-    RequestHandler: StorageReaderServerHandler<Request, Response>,
+    RequestHandler: StorageReaderServerHandler<Request, Response> + Clone,
     Request: Serialize + DeserializeOwned + Send + 'static,
     Response: Serialize + DeserializeOwned + Send + 'static,
 {
@@ -64,7 +82,8 @@ where
         request_handler: RequestHandler,
         config: ServerConfig,
     ) -> Self {
-        Self { storage_reader, request_handler, config, _req_res: PhantomData }
+        let app_state = AppState { storage_reader, request_handler, _req_res: PhantomData };
+        Self { app_state, config }
     }
 
     /// Starts the server to handle incoming requests.