feat: hot-reloading of config file

config-example.toml

@@ -10,6 +10,9 @@
 listen_port = 8080
 listen_port_tls = 8443
 
+# Optional for h2 and http1.1
+tcp_listen_backlog = 1024
+
 # Optional for h2 and http1.1
 max_concurrent_streams = 100
 

rpxy-bin/Cargo.toml

@@ -35,7 +35,7 @@ rustls-pemfile = "1.0.3"
 # config
 clap = { version = "4.3.17", features = ["std", "cargo", "wrap_help"] }
 toml = { version = "0.7.6", default-features = false, features = ["parse"] }
-# hot_reload = "0.1.2"
+hot_reload = "0.1.4"
 
 # logging
 tracing = { version = "0.1.37" }

rpxy-bin/src/config/mod.rs

@@ -1,4 +1,9 @@
 mod parse;
+mod service;
 mod toml;
 
-pub use parse::build_settings;
+pub use {
+  self::toml::ConfigToml,
+  parse::{build_settings, parse_opts},
+  service::ConfigTomlReloader,
+};

rpxy-bin/src/config/parse.rs

@@ -7,28 +7,30 @@ use crate::{
 use clap::Arg;
 use rpxy_lib::{AppConfig, AppConfigList, ProxyConfig};
 
-pub fn build_settings() -> std::result::Result<(ProxyConfig, AppConfigList<CryptoFileSource>), anyhow::Error> {
+pub fn parse_opts() -> Result<String, anyhow::Error> {
   let _ = include_str!("../../Cargo.toml");
   let options = clap::command!().arg(
     Arg::new("config_file")
       .long("config")
       .short('c')
       .value_name("FILE")
-      .help("Configuration file path like \"./config.toml\""),
+      .required(true)
+      .help("Configuration file path like ./config.toml"),
   );
   let matches = options.get_matches();
 
   ///////////////////////////////////
-  let config = if let Some(config_file_path) = matches.get_one::<String>("config_file") {
+  let config_file_path = matches.get_one::<String>("config_file").unwrap();
-    ConfigToml::new(config_file_path)?
-  } else {
-    // Default config Toml
-    ConfigToml::default()
-  };
 
+  Ok(config_file_path.to_string())
+}
+
+pub fn build_settings(
+  config: &ConfigToml,
+) -> std::result::Result<(ProxyConfig, AppConfigList<CryptoFileSource>), anyhow::Error> {
   ///////////////////////////////////
   // build proxy config
-  let proxy_config: ProxyConfig = (&config).try_into()?;
+  let proxy_config: ProxyConfig = config.try_into()?;
   // For loggings
   if proxy_config.listen_sockets.iter().any(|addr| addr.is_ipv6()) {
     info!("Listen both IPv4 and IPv6")
@@ -50,7 +52,7 @@ pub fn build_settings() -> std::result::Result<(ProxyConfig, AppConfigList<Crypt
 
   ///////////////////////////////////
   // backend_apps
-  let apps = config.apps.ok_or(anyhow!("Missing application spec"))?;
+  let apps = config.apps.clone().ok_or(anyhow!("Missing application spec"))?;
 
   // assertions for all backend apps
   ensure!(!apps.0.is_empty(), "Wrong application spec.");
@@ -88,9 +90,8 @@ pub fn build_settings() -> std::result::Result<(ProxyConfig, AppConfigList<Crypt
 
   let app_config_list = AppConfigList {
     inner: app_config_list_inner,
-    default_app: config.default_app.map(|v| v.to_ascii_lowercase()), // default backend application for plaintext http requests
+    default_app: config.default_app.clone().map(|v| v.to_ascii_lowercase()), // default backend application for plaintext http requests
   };
 
   Ok((proxy_config, app_config_list))
-  // todo!()
 }

rpxy-bin/src/config/service.rs

@@ -0,0 +1,24 @@
+use super::toml::ConfigToml;
+use async_trait::async_trait;
+use hot_reload::{Reload, ReloaderError};
+
+#[derive(Clone)]
+pub struct ConfigTomlReloader {
+  pub config_path: String,
+}
+
+#[async_trait]
+impl Reload<ConfigToml> for ConfigTomlReloader {
+  type Source = String;
+  async fn new(source: &Self::Source) -> Result<Self, ReloaderError<ConfigToml>> {
+    Ok(Self {
+      config_path: source.clone(),
+    })
+  }
+
+  async fn reload(&self) -> Result<Option<ConfigToml>, ReloaderError<ConfigToml>> {
+    let conf = ConfigToml::new(&self.config_path)
+      .map_err(|_e| ReloaderError::<ConfigToml>::Reload("Failed to reload config toml"))?;
+    Ok(Some(conf))
+  }
+}

rpxy-bin/src/config/toml.rs

@@ -8,11 +8,12 @@ use rustc_hash::FxHashMap as HashMap;
 use serde::Deserialize;
 use std::{fs, net::SocketAddr};
 
-#[derive(Deserialize, Debug, Default)]
+#[derive(Deserialize, Debug, Default, PartialEq, Eq, Clone)]
 pub struct ConfigToml {
   pub listen_port: Option<u16>,
   pub listen_port_tls: Option<u16>,
   pub listen_ipv6: Option<bool>,
+  pub tcp_listen_backlog: Option<u32>,
   pub max_concurrent_streams: Option<u32>,
   pub max_clients: Option<u32>,
   pub apps: Option<Apps>,
@@ -21,7 +22,7 @@ pub struct ConfigToml {
 }
 
 #[cfg(feature = "http3")]
-#[derive(Deserialize, Debug, Default)]
+#[derive(Deserialize, Debug, Default, PartialEq, Eq, Clone)]
 pub struct Http3Option {
   pub alt_svc_max_age: Option<u32>,
   pub request_max_body_size: Option<usize>,
@@ -31,24 +32,24 @@ pub struct Http3Option {
   pub max_idle_timeout: Option<u64>,
 }
 
-#[derive(Deserialize, Debug, Default)]
+#[derive(Deserialize, Debug, Default, PartialEq, Eq, Clone)]
 pub struct Experimental {
   #[cfg(feature = "http3")]
   pub h3: Option<Http3Option>,
   pub ignore_sni_consistency: Option<bool>,
 }
 
-#[derive(Deserialize, Debug, Default)]
+#[derive(Deserialize, Debug, Default, PartialEq, Eq, Clone)]
 pub struct Apps(pub HashMap<String, Application>);
 
-#[derive(Deserialize, Debug, Default)]
+#[derive(Deserialize, Debug, Default, PartialEq, Eq, Clone)]
 pub struct Application {
   pub server_name: Option<String>,
   pub reverse_proxy: Option<Vec<ReverseProxyOption>>,
   pub tls: Option<TlsOption>,
 }
 
-#[derive(Deserialize, Debug, Default)]
+#[derive(Deserialize, Debug, Default, PartialEq, Eq, Clone)]
 pub struct TlsOption {
   pub tls_cert_path: Option<String>,
   pub tls_cert_key_path: Option<String>,
@@ -56,7 +57,7 @@ pub struct TlsOption {
   pub client_ca_cert_path: Option<String>,
 }
 
-#[derive(Deserialize, Debug, Default)]
+#[derive(Deserialize, Debug, Default, PartialEq, Eq, Clone)]
 pub struct ReverseProxyOption {
   pub path: Option<String>,
   pub replace_path: Option<String>,
@@ -65,7 +66,7 @@ pub struct ReverseProxyOption {
   pub load_balance: Option<String>,
 }
 
-#[derive(Deserialize, Debug, Default)]
+#[derive(Deserialize, Debug, Default, PartialEq, Eq, Clone)]
 pub struct UpstreamParams {
   pub location: String,
   pub tls: Option<bool>,
@@ -112,6 +113,11 @@ impl TryInto<ProxyConfig> for &ConfigToml {
       })
       .collect();
 
+    // tcp backlog
+    if let Some(backlog) = self.tcp_listen_backlog {
+      proxy_config.tcp_listen_backlog = backlog;
+    }
+
     // max values
     if let Some(c) = self.max_clients {
       proxy_config.max_clients = c as usize;

rpxy-bin/src/constants.rs

@@ -1,2 +1,3 @@
 pub const LISTEN_ADDRESSES_V4: &[&str] = &["0.0.0.0"];
 pub const LISTEN_ADDRESSES_V6: &[&str] = &["[::]"];
+pub const CONFIG_WATCH_DELAY_SECS: u32 = 20;

rpxy-bin/src/main.rs

@@ -11,7 +11,12 @@ mod constants;
 mod error;
 mod log;
 
-use crate::{config::build_settings, log::*};
+use crate::{
+  config::{build_settings, parse_opts, ConfigToml, ConfigTomlReloader},
+  constants::CONFIG_WATCH_DELAY_SECS,
+  log::*,
+};
+use hot_reload::{ReloaderReceiver, ReloaderService};
 use rpxy_lib::entrypoint;
 
 fn main() {
@@ -23,17 +28,68 @@ fn main() {
   let runtime = runtime_builder.build().unwrap();
 
   runtime.block_on(async {
-    let (proxy_conf, app_conf) = match build_settings() {
+    // Initially load config
-      Ok(g) => g,
+    let Ok(config_path) = parse_opts() else {
-      Err(e) => {
+        error!("Invalid toml file");
-        error!("Invalid configuration: {}", e);
         std::process::exit(1);
-      }
     };
+    let (config_service, config_rx) =
+      ReloaderService::<ConfigTomlReloader, ConfigToml>::new(&config_path, CONFIG_WATCH_DELAY_SECS, false)
+        .await
+        .unwrap();
 
-    entrypoint(proxy_conf, app_conf, runtime.handle().clone())
+    tokio::select! {
-      .await
+      _ = config_service.start() => {
-      .unwrap()
+        error!("config reloader service exited");
+      }
+      _ = rpxy_service(config_rx, runtime.handle().clone()) => {
+        error!("rpxy service existed");
+      }
+    }
   });
-  warn!("rpxy exited!");
+}
+
+async fn rpxy_service(
+  mut config_rx: ReloaderReceiver<ConfigToml>,
+  runtime_handle: tokio::runtime::Handle,
+) -> Result<(), anyhow::Error> {
+  // Initial loading
+  config_rx.changed().await?;
+  let config_toml = config_rx.borrow().clone().unwrap();
+  let (mut proxy_conf, mut app_conf) = match build_settings(&config_toml) {
+    Ok(v) => v,
+    Err(e) => {
+      error!("Invalid configuration: {e}");
+      return Err(anyhow::anyhow!(e));
+    }
+  };
+
+  // Continuous monitoring
+  loop {
+    tokio::select! {
+      _ = entrypoint(&proxy_conf, &app_conf, &runtime_handle) => {
+        error!("rpxy entrypoint exited");
+        break;
+      }
+      _ = config_rx.changed() => {
+        if config_rx.borrow().is_none() {
+          error!("Something wrong in config reloader receiver");
+          break;
+        }
+        let config_toml = config_rx.borrow().clone().unwrap();
+        match build_settings(&config_toml) {
+          Ok((p, a)) => {
+            (proxy_conf, app_conf) = (p, a)
+          },
+          Err(e) => {
+            error!("Invalid configuration. Configuration does not updated: {e}");
+            continue;
+          }
+        };
+        info!("Configuration updated. Force to re-bind TCP/UDP sockets");
+      }
+      else => break
+    }
+  }
+  Ok(())
 }

rpxy-lib/Cargo.toml

@@ -30,7 +30,7 @@ tokio = { version = "1.29.1", default-features = false, features = [
   "macros",
 ] }
 async-trait = "0.1.72"
-hot_reload = "0.1.2" # reloading certs
+hot_reload = "0.1.4" # reloading certs
 
 # Error handling
 anyhow = "1.0.72"
@@ -63,6 +63,8 @@ quinn = { path = "../quinn/quinn", optional = true } # Tentative to support rust
 h3 = { path = "../h3/h3/", optional = true }
 # h3-quinn = { path = "./h3/h3-quinn/", optional = true }
 h3-quinn = { path = "../h3-quinn/", optional = true } # Tentative to support rustls-0.21
+# for UDP socket wit SO_REUSEADDR
+socket2 = { version = "0.5.3", features = ["all"] }
 
 # cookie handling for sticky cookie
 chrono = { version = "0.4.26", default-features = false, features = [

rpxy-lib/src/constants.rs

@@ -1,5 +1,6 @@
 // pub const LISTEN_ADDRESSES_V4: &[&str] = &["0.0.0.0"];
 // pub const LISTEN_ADDRESSES_V6: &[&str] = &["[::]"];
+pub const TCP_LISTEN_BACKLOG: u32 = 1024;
 // pub const HTTP_LISTEN_PORT: u16 = 8080;
 // pub const HTTPS_LISTEN_PORT: u16 = 8443;
 pub const PROXY_TIMEOUT_SEC: u64 = 60;

rpxy-lib/src/globals.rs

@@ -36,11 +36,12 @@ where
 }
 
 /// Configuration parameters for proxy transport and request handlers
-#[derive(PartialEq, Eq)]
+#[derive(PartialEq, Eq, Clone)]
 pub struct ProxyConfig {
   pub listen_sockets: Vec<SocketAddr>, // when instantiate server
   pub http_port: Option<u16>,          // when instantiate server
   pub https_port: Option<u16>,         // when instantiate server
+  pub tcp_listen_backlog: u32,         // when instantiate server
 
   pub proxy_timeout: Duration,    // when serving requests at Proxy
   pub upstream_timeout: Duration, // when serving requests at Handler
@@ -74,6 +75,7 @@ impl Default for ProxyConfig {
       listen_sockets: Vec::new(),
       http_port: None,
       https_port: None,
+      tcp_listen_backlog: TCP_LISTEN_BACKLOG,
 
       // TODO: Reconsider each timeout values
       proxy_timeout: Duration::from_secs(PROXY_TIMEOUT_SEC),
@@ -104,7 +106,7 @@ impl Default for ProxyConfig {
 }
 
 /// Configuration parameters for backend applications
-#[derive(PartialEq, Eq)]
+#[derive(PartialEq, Eq, Clone)]
 pub struct AppConfigList<T>
 where
   T: CryptoSource,
@@ -152,7 +154,7 @@ where
 }
 
 /// Configuration parameters for single backend application
-#[derive(PartialEq, Eq)]
+#[derive(PartialEq, Eq, Clone)]
 pub struct AppConfig<T>
 where
   T: CryptoSource,
@@ -234,7 +236,7 @@ where
 }
 
 /// Configuration parameters for single reverse proxy corresponding to the path
-#[derive(PartialEq, Eq)]
+#[derive(PartialEq, Eq, Clone)]
 pub struct ReverseProxyConfig {
   pub path: Option<String>,
   pub replace_path: Option<String>,
@@ -244,7 +246,7 @@ pub struct ReverseProxyConfig {
 }
 
 /// Configuration parameters for single upstream destination from a reverse proxy
-#[derive(PartialEq, Eq)]
+#[derive(PartialEq, Eq, Clone)]
 pub struct UpstreamUri {
   pub inner: hyper::Uri,
 }
@@ -259,7 +261,7 @@ impl TryInto<Upstream> for &UpstreamUri {
 }
 
 /// Configuration parameters on TLS for a single backend application
-#[derive(PartialEq, Eq)]
+#[derive(PartialEq, Eq, Clone)]
 pub struct TlsConfig<T>
 where
   T: CryptoSource,

rpxy-lib/src/lib.rs

@@ -25,19 +25,19 @@ pub mod reexports {
 
 /// Entrypoint that creates and spawns tasks of reverse proxy services
 pub async fn entrypoint<T>(
-  proxy_config: ProxyConfig,
+  proxy_config: &ProxyConfig,
-  app_config_list: AppConfigList<T>,
+  app_config_list: &AppConfigList<T>,
-  runtime_handle: tokio::runtime::Handle,
+  runtime_handle: &tokio::runtime::Handle,
 ) -> Result<()>
 where
   T: CryptoSource + Clone + Send + Sync + 'static,
 {
   // build global
   let globals = Arc::new(Globals {
-    proxy_config,
+    proxy_config: proxy_config.clone(),
-    backends: app_config_list.try_into()?,
+    backends: app_config_list.clone().try_into()?,
     request_count: Default::default(),
-    runtime_handle,
+    runtime_handle: runtime_handle.clone(),
   });
   // let connector = TrustDnsResolver::default().into_rustls_webpki_https_connector();
   let connector = hyper_rustls::HttpsConnectorBuilder::new()
@@ -71,8 +71,8 @@ where
   }));
 
   // wait for all future
-  if let (Ok(_), _, _) = futures.await {
+  if let (Ok(Err(e)), _, _) = futures.await {
-    error!("Some proxy services are down");
+    error!("Some proxy services are down: {:?}", e);
   };
 
   Ok(())

rpxy-lib/src/proxy/mod.rs

@@ -4,5 +4,6 @@ mod proxy_client_cert;
 mod proxy_h3;
 mod proxy_main;
 mod proxy_tls;
+mod socket;
 
 pub use proxy_main::{Proxy, ProxyBuilder, ProxyBuilderError};

rpxy-lib/src/proxy/proxy_main.rs

@@ -1,4 +1,4 @@
-// use super::proxy_handler::handle_request;
+use super::socket::bind_tcp_socket;
 use crate::{
   certs::CryptoSource, error::*, globals::Globals, handler::HttpMessageHandler, log::*, utils::ServerNameBytesExp,
 };
@@ -7,7 +7,6 @@ use hyper::{client::connect::Connect, server::conn::Http, service::service_fn, B
 use std::{net::SocketAddr, sync::Arc};
 use tokio::{
   io::{AsyncRead, AsyncWrite},
-  net::TcpListener,
   runtime::Handle,
   time::{timeout, Duration},
 };
@@ -94,7 +93,9 @@ where
 
   async fn start_without_tls(self, server: Http<LocalExecutor>) -> Result<()> {
     let listener_service = async {
-      let tcp_listener = TcpListener::bind(&self.listening_on).await?;
+      let tcp_socket = bind_tcp_socket(&self.listening_on)?;
+      let tcp_listener = tcp_socket.listen(self.globals.proxy_config.tcp_listen_backlog)?;
+      // let tcp_listener = TcpListener::bind(&self.listening_on).await?;
       info!("Start TCP proxy serving with HTTP request for configured host names");
       while let Ok((stream, _client_addr)) = tcp_listener.accept().await {
         self.clone().client_serve(stream, server.clone(), _client_addr, None);

rpxy-lib/src/proxy/proxy_tls.rs

@@ -1,6 +1,9 @@
+#[cfg(feature = "http3")]
+use super::socket::bind_udp_socket;
 use super::{
   crypto_service::{CryptoReloader, ServerCrypto, ServerCryptoBase, SniServerCryptoMap},
   proxy_main::{LocalExecutor, Proxy},
+  socket::bind_tcp_socket,
 };
 use crate::{certs::CryptoSource, constants::*, error::*, log::*, utils::BytesName};
 use hot_reload::{ReloaderReceiver, ReloaderService};
@@ -10,10 +13,7 @@ use quinn::{crypto::rustls::HandshakeData, Endpoint, ServerConfig as QuicServerC
 #[cfg(feature = "http3")]
 use rustls::ServerConfig;
 use std::sync::Arc;
-use tokio::{
+use tokio::time::{timeout, Duration};
-  net::TcpListener,
-  time::{timeout, Duration},
-};
 
 impl<T, U> Proxy<T, U>
 where
@@ -26,7 +26,8 @@ where
     server: Http<LocalExecutor>,
     mut server_crypto_rx: ReloaderReceiver<ServerCryptoBase>,
   ) -> Result<()> {
-    let tcp_listener = TcpListener::bind(&self.listening_on).await?;
+    let tcp_socket = bind_tcp_socket(&self.listening_on)?;
+    let tcp_listener = tcp_socket.listen(self.globals.proxy_config.tcp_listen_backlog)?;
     info!("Start TCP proxy serving with HTTPS request for configured host names");
 
     let mut server_crypto_map: Option<Arc<SniServerCryptoMap>> = None;
@@ -130,7 +131,17 @@ where
     let mut server_config_h3 = QuicServerConfig::with_crypto(Arc::new(rustls_server_config));
     server_config_h3.transport = Arc::new(transport_config_quic);
     server_config_h3.concurrent_connections(self.globals.proxy_config.h3_max_concurrent_connections);
-    let endpoint = Endpoint::server(server_config_h3, self.listening_on)?;
+
+    // To reuse address
+    let udp_socket = bind_udp_socket(&self.listening_on)?;
+    let runtime = quinn::default_runtime()
+      .ok_or_else(|| std::io::Error::new(std::io::ErrorKind::Other, "No async runtime found"))?;
+    let endpoint = Endpoint::new(
+      quinn::EndpointConfig::default(),
+      Some(server_config_h3),
+      udp_socket,
+      runtime,
+    )?;
 
     let mut server_crypto: Option<Arc<ServerCrypto>> = None;
     loop {
@@ -199,10 +210,10 @@ where
     #[cfg(not(feature = "http3"))]
     {
       tokio::select! {
-        _= self.cert_service(tx) => {
+        _= cert_reloader_service.start() => {
           error!("Cert service for TLS exited");
         },
-        _ = self.listener_service(server, rx) => {
+        _ = self.listener_service(server, cert_reloader_rx) => {
           error!("TCP proxy service for TLS exited");
         },
         else => {

rpxy-lib/src/proxy/socket.rs

@@ -0,0 +1,41 @@
+use crate::{error::*, log::*};
+#[cfg(feature = "http3")]
+use socket2::{Domain, Protocol, Socket, Type};
+use std::net::SocketAddr;
+#[cfg(feature = "http3")]
+use std::net::UdpSocket;
+use tokio::net::TcpSocket;
+
+pub(super) fn bind_tcp_socket(listening_on: &SocketAddr) -> Result<TcpSocket> {
+  let tcp_socket = if listening_on.is_ipv6() {
+    TcpSocket::new_v6()
+  } else {
+    TcpSocket::new_v4()
+  }?;
+  tcp_socket.set_reuseaddr(true)?;
+  tcp_socket.set_reuseport(true)?;
+  if let Err(e) = tcp_socket.bind(*listening_on) {
+    error!("Failed to bind TCP socket: {}", e);
+    return Err(RpxyError::Io(e));
+  };
+  Ok(tcp_socket)
+}
+
+#[cfg(feature = "http3")]
+pub(super) fn bind_udp_socket(listening_on: &SocketAddr) -> Result<UdpSocket> {
+  let socket = if listening_on.is_ipv6() {
+    Socket::new(Domain::IPV6, Type::DGRAM, Some(Protocol::UDP))
+  } else {
+    Socket::new(Domain::IPV4, Type::DGRAM, Some(Protocol::UDP))
+  }?;
+  socket.set_reuse_address(true)?;
+  socket.set_reuse_port(true)?;
+
+  if let Err(e) = socket.bind(&(*listening_on).into()) {
+    error!("Failed to bind UDP socket: {}", e);
+    return Err(RpxyError::Io(e));
+  };
+  let udp_socket: UdpSocket = socket.into();
+
+  Ok(udp_socket)
+}