refactor: expose Store Traits and add ToMcpServerHandler for Improved Framework Flexibility (#107)

* refactor: expose session store and event store traits and
implementations

* chore: update cargo feature

Author: hashemix

crates/rust-mcp-sdk/src/hyper_servers/server.rs

@@ -5,10 +5,11 @@ use crate::{
         utils::{
             DEFAULT_MESSAGES_ENDPOINT, DEFAULT_SSE_ENDPOINT, DEFAULT_STREAMABLE_HTTP_ENDPOINT,
         },
-        InMemorySessionStore, McpAppState,
+        McpAppState,
     },
     mcp_server::hyper_runtime::HyperRuntime,
     mcp_traits::{mcp_handler::McpServerHandler, IdGenerator},
+    session_store::InMemorySessionStore,
 };
 #[cfg(feature = "ssl")]
 use axum_server::tls_rustls::RustlsConfig;

crates/rust-mcp-sdk/src/lib.rs

@@ -7,6 +7,8 @@ pub(crate) mod mcp_http;
 mod mcp_macros;
 mod mcp_runtimes;
 mod mcp_traits;
+#[cfg(any(feature = "server", feature = "hyper-server"))]
+pub mod session_store;
 mod utils;
 
 #[cfg(feature = "client")]
@@ -65,7 +67,7 @@ pub mod mcp_server {
     //!   handle each message based on its type and parameters.
     //!
     //! Refer to [examples/hello-world-mcp-server-stdio-core](https://github.com/rust-mcp-stack/rust-mcp-sdk/tree/main/examples/hello-world-mcp-server-stdio-core) for an example.
-    pub use super::mcp_handlers::mcp_server_handler::ServerHandler;
+    pub use super::mcp_handlers::mcp_server_handler::{ServerHandler, ToMcpServerHandler};
     pub use super::mcp_handlers::mcp_server_handler_core::ServerHandlerCore;
 
     pub use super::mcp_runtimes::server_runtime::mcp_server_runtime as server_runtime;
@@ -79,6 +81,9 @@ pub mod mcp_server {
     #[cfg(feature = "hyper-server")]
     pub use super::hyper_servers::*;
     pub use super::utils::enforce_compatible_protocol_version;
+
+    #[cfg(feature = "hyper-server")]
+    pub use super::mcp_http::{McpAppState, McpHttpHandler};
 }
 
 #[cfg(feature = "client")]

crates/rust-mcp-sdk/src/mcp_handlers/mcp_server_handler.rs

@@ -1,4 +1,8 @@
-use crate::schema::{schema_utils::CallToolError, *};
+use crate::{
+    mcp_server::server_runtime::ServerRuntimeInternalHandler,
+    mcp_traits::mcp_handler::McpServerHandler,
+    schema::{schema_utils::CallToolError, *},
+};
 use async_trait::async_trait;
 use serde_json::Value;
 use std::sync::Arc;
@@ -326,3 +330,14 @@ pub trait ServerHandler: Send + Sync + 'static {
         Ok(())
     }
 }
+
+// Custom trait for conversion
+pub trait ToMcpServerHandler {
+    fn to_mcp_server_handler(self) -> Arc<dyn McpServerHandler + 'static>;
+}
+
+impl<T: ServerHandler + 'static> ToMcpServerHandler for T {
+    fn to_mcp_server_handler(self) -> Arc<dyn McpServerHandler + 'static> {
+        Arc::new(ServerRuntimeInternalHandler::new(Box::new(self)))
+    }
+}

crates/rust-mcp-sdk/src/mcp_http.rs

@@ -1,11 +1,9 @@
 mod app_state;
 mod mcp_http_handler;
 pub(crate) mod mcp_http_utils;
-mod session_store;
 
-pub(crate) use app_state::*;
+pub use app_state::*;
 pub use mcp_http_handler::*;
-pub use session_store::*;
 
 pub(crate) mod utils {
     pub use super::mcp_http_utils::*;

crates/rust-mcp-sdk/src/mcp_http/app_state.rs

@@ -1,12 +1,9 @@
-use std::{sync::Arc, time::Duration};
-
-use super::session_store::SessionStore;
 use crate::mcp_traits::mcp_handler::McpServerHandler;
+use crate::session_store::SessionStore;
 use crate::{id_generator::FastIdGenerator, mcp_traits::IdGenerator, schema::InitializeResult};
-
 use rust_mcp_transport::event_store::EventStore;
-
 use rust_mcp_transport::{SessionId, TransportOptions};
+use std::{sync::Arc, time::Duration};
 
 /// Application state struct for the Hyper ser
 ///

crates/rust-mcp-sdk/src/mcp_http/session_store.rs renamed to crates/rust-mcp-sdk/src/session_store.rs

@@ -1,15 +1,15 @@
-mod in_memory;
+mod in_memory_session_store;
 use std::sync::Arc;
 
 use async_trait::async_trait;
-pub use in_memory::*;
+pub use in_memory_session_store::*;
 use rust_mcp_transport::SessionId;
 use tokio::sync::Mutex;
 
 use crate::mcp_server::ServerRuntime;
 
 // Type alias for the server-side duplex stream used in sessions
-pub type TxServer = Arc<ServerRuntime>;
+type TxServer = Arc<ServerRuntime>;
 
 /// Trait defining the interface for session storage operations
 ///