restructure into multiple crates

add mcp server collection

mcp_server_collection/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "mcp_server_collection"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+rmcp = { version = "1.3.0", features = ["server", "transport-streamable-http-server-session", "transport-streamable-http-server"] }
+chrono = "0.4.44"
+axum = "0.8.8"
+serde = { version = "1.0.228", features = ["derive"] }
+tokio = { version = "1.51.0", features = ["full"] }
+own_assist_common = {path="../common"}
+tokio-util = "0.7.18"
+
+[features]
+datetime = []

mcp_server_collection/src/config.rs

@@ -0,0 +1,21 @@
+use serde::Deserialize;
+use own_assist_common::config_from_file;
+use own_assist_common::config_loader::ConfigLoadingError;
+use crate::McpServiceType;
+
+#[derive(Debug, Deserialize)]
+pub(crate) struct Config {
+    pub(crate) servers: Vec<ServerConfig>,
+}
+
+#[derive(Debug, Deserialize)]
+pub(crate) struct ServerConfig {
+    pub(crate) path: String,
+    pub(crate) r#type: McpServiceType
+}
+
+impl Config {
+    pub fn from_file() -> Result<Self, ConfigLoadingError> {
+        config_from_file("servers.toml")
+    }
+}

mcp_server_collection/src/datetime.rs

@@ -0,0 +1,47 @@
+use chrono::{Datelike, Local};
+use rmcp::model::{Implementation, ServerCapabilities, ServerInfo};
+use rmcp::{tool, tool_handler, tool_router, ServerHandler};
+use rmcp::handler::server::tool::ToolRouter;
+use crate::McpServerHandler;
+
+#[derive(Debug, Clone)]
+pub struct DateTimeHandler {
+    tool_router: ToolRouter<Self>
+}
+
+impl McpServerHandler for DateTimeHandler {
+    fn new() -> Self {
+        DateTimeHandler { tool_router: Self::tool_router() }
+    }
+}
+
+#[tool_router]
+impl DateTimeHandler {
+    #[tool(description = "returns the local datetime in ISO 8601", annotations(read_only_hint = true))]
+    fn get_local_datetime() -> String {
+        Local::now().format("%+").to_string()
+    }
+
+    #[tool(description = "returns the utc datetime in ISO 8601", annotations(read_only_hint = true))]
+    fn get_utc_datetime() -> String {
+        Local::now().format("%+").to_string()
+    }
+
+    #[tool(description = "return current week number in year", annotations(read_only_hint = true))]
+    fn get_week() -> String {
+        Local::now().iso_week().week().to_string()
+    }
+
+    #[tool(description = "return current weekday as 3-character-string (e.g. Mon, Tue, ...)", annotations(read_only_hint = true))]
+    fn get_weekday() -> String {
+        Local::now().weekday().to_string()
+    }
+}
+
+#[tool_handler]
+impl ServerHandler for DateTimeHandler {
+    fn get_info(&self) -> ServerInfo {
+        ServerInfo::new(ServerCapabilities::builder().enable_tools().build())
+            .with_instructions("A simple clock/datetime provider. It is read only and thus safe to use.".to_string()).with_server_info(Implementation::new("datetime", env!("CARGO_PKG_VERSION")))
+    }
+}

mcp_server_collection/src/main.rs

@@ -0,0 +1,63 @@
+#[cfg(feature = "datetime")]
+pub mod datetime;
+mod config;
+
+use axum::Router;
+use rmcp::transport::{
+    StreamableHttpServerConfig,
+    streamable_http_server::{session::local::LocalSessionManager, tower::StreamableHttpService},
+};
+use serde::Deserialize;
+use tokio::main;
+use crate::config::{Config, ServerConfig};
+#[cfg(feature = "datetime")]
+use crate::datetime::DateTimeHandler;
+
+pub trait McpServerHandler: rmcp::ServerHandler {
+    fn new() -> Self;
+
+    fn mcp_service() -> StreamableHttpService<Self, LocalSessionManager> {
+        StreamableHttpService::new(|| Ok(Self::new()), LocalSessionManager::default().into(), StreamableHttpServerConfig::default())
+    }
+}
+
+#[derive(Debug, Deserialize)]
+#[non_exhaustive]
+pub enum McpServiceType {
+    DateTime
+}
+
+pub(crate) fn mcp_router(server_configs: Vec<ServerConfig>) -> Router {
+    let mut router = Router::new();
+
+    for config in &server_configs {
+        router = match config.r#type {
+            McpServiceType::DateTime => {
+                router.route_service(config.path.as_str(), DateTimeHandler::mcp_service())
+            }
+        }
+    }
+
+    router
+}
+
+#[main]
+async fn main() {
+    let config = Config::from_file().inspect_err(|e|{
+        eprintln!("Error loading config: {}", e); // FIXME: use actual logger instead
+        std::process::exit(1);
+    }).unwrap();
+
+    let router = mcp_router(config.servers);
+
+    let tcp_listener = tokio::net::TcpListener::bind("127.0.0.1:8000").await.unwrap(); // use toml config
+
+    let ct = tokio_util::sync::CancellationToken::new();
+
+    let _ = axum::serve(tcp_listener, router)
+        .with_graceful_shutdown(async move {
+            tokio::signal::ctrl_c().await.unwrap();
+            ct.cancel();
+        })
+        .await;
+}