feat: Adding apollo-mcp-proxy crate and adding a set of proxy config values for it

Author: alocay

Cargo.lock

@@ -4,6 +4,7 @@ members = [
   "crates/apollo-mcp-server",
   "crates/apollo-mcp-registry",
   "crates/apollo-schema-index",
+  "crates/apollo-mcp-proxy",
 ]
 
 [workspace.package]
@@ -13,6 +14,7 @@ version = "0.7.3"
 [workspace.dependencies]
 apollo-compiler = "1.27.0"
 apollo-federation = "2.1.3"
+axum = "0.8.4"
 futures = { version = "0.3.31", features = ["thread-pool"] }
 insta = { version = "1.43.1", features = [
   "json",
@@ -25,6 +27,12 @@ reqwest = { version = "0.12.15", default-features = false, features = [
   "json",
   "native-tls-vendored",
 ] }
+rmcp = { version = "0.2", features = [
+  "server",
+  "transport-io",
+  "transport-sse-server",
+  "transport-streamable-http-server",
+] }
 rstest = "0.25.0"
 secrecy = { version = "0.10.3", features = ["serde"] }
 serde = { version = "1.0.219", features = ["derive"] }

Cargo.toml

@@ -0,0 +1,21 @@
+[package]
+name = "apollo-mcp-proxy"
+edition = "2024"
+authors.workspace = true
+version.workspace = true
+
+[dependencies]
+axum.workspace = true
+clap = { version = "4.5.40", features = ["derive"] }
+tokio.workspace = true
+rmcp = { workspace = true, features = [
+    "client",
+    "reqwest",
+    "transport-streamable-http-client",
+]}
+tracing.workspace = true
+tracing-appender = "0.2.3"
+tracing-subscriber.workspace = true
+
+[lints]
+workspace = true

crates/apollo-mcp-proxy/Cargo.toml

@@ -0,0 +1,42 @@
+use crate::server::ProxyServer;
+use rmcp::transport::stdio;
+use rmcp::{
+    ServiceExt,
+    model::{ClientCapabilities, ClientInfo, Implementation},
+    transport::StreamableHttpClientTransport,
+};
+use std::error::Error;
+use tracing::{debug, error, info};
+
+pub async fn start_proxy_client(url: &str) -> Result<(), Box<dyn Error>> {
+    let transport = StreamableHttpClientTransport::from_uri(url);
+    let client_info = ClientInfo {
+        protocol_version: Default::default(),
+        capabilities: ClientCapabilities::default(),
+        client_info: Implementation {
+            name: "mcp remote rust client".to_string(),
+            version: env!("CARGO_PKG_VERSION").to_string(),
+        },
+    };
+
+    let client = match client_info.serve(transport).await.inspect_err(|e| {
+        error!("[Proxy] client error: {:?}", e);
+    }) {
+        Ok(client) => client,
+        Err(e) => {
+            error!("[Proxy] client startup error: {:?}", e);
+            return Err(e.into());
+        }
+    };
+
+    let server_info = client.peer_info();
+    info!("[Proxy] Connected to server");
+    debug!("{server_info:#?}");
+
+    let proxy_server = ProxyServer::new(client.peer().clone(), client.peer_info());
+    let stdio_transport = stdio();
+    let server = proxy_server.serve(stdio_transport).await?;
+
+    server.waiting().await?;
+    Ok(())
+}

crates/apollo-mcp-proxy/src/client.rs

@@ -0,0 +1,3 @@
+pub mod client;
+
+pub mod server;

crates/apollo-mcp-proxy/src/lib.rs

@@ -0,0 +1,34 @@
+use clap::Parser;
+use apollo_mcp_proxy::client::start_proxy_client;
+use std::error::Error;
+use tracing_appender::rolling::{RollingFileAppender, Rotation};
+use tracing_subscriber::layer::SubscriberExt;
+use tracing_subscriber::util::SubscriberInitExt;
+
+#[derive(Parser)]
+struct Args {
+    #[arg(short, long)]
+    url: String,
+}
+
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn Error>> {
+    // Initialize logging
+    let file_appender = RollingFileAppender::builder()
+        .rotation(Rotation::NEVER)
+        .filename_prefix("apollo_mcp_proxy")
+        .filename_suffix("log")
+        .build("./logs")?;
+
+    let (non_blocking_writer, _guard) = tracing_appender::non_blocking(file_appender);
+
+    tracing_subscriber::registry()
+        .with(tracing_subscriber::fmt::layer().with_writer(non_blocking_writer))
+        .init();
+
+    let args = Args::parse();
+
+    let _ = start_proxy_client(&args.url).await;
+
+    Ok(())
+}