graceful api shutdown (#3677)

src/bin/cmd/server.rs

@@ -25,21 +25,27 @@ use crate::config::GlobalConfig;
 use crate::p2p::Seeding;
 use crate::servers;
 use crate::tui::ui;
+use futures::channel::oneshot;
 use grin_p2p::msg::PeerAddrs;
 use grin_p2p::PeerAddr;
 use grin_util::logger::LogEntry;
 use std::sync::mpsc;
 
 /// wrap below to allow UI to clean up on stop
-pub fn start_server(config: servers::ServerConfig, logs_rx: Option<mpsc::Receiver<LogEntry>>) {
-	start_server_tui(config, logs_rx);
-	// Just kill process for now, otherwise the process
-	// hangs around until sigint because the API server
-	// currently has no shutdown facility
+pub fn start_server(
+	config: servers::ServerConfig,
+	logs_rx: Option<mpsc::Receiver<LogEntry>>,
+	api_chan: &'static mut (oneshot::Sender<()>, oneshot::Receiver<()>),
+) {
+	start_server_tui(config, logs_rx, api_chan);
 	exit(0);
 }
 
-fn start_server_tui(config: servers::ServerConfig, logs_rx: Option<mpsc::Receiver<LogEntry>>) {
+fn start_server_tui(
+	config: servers::ServerConfig,
+	logs_rx: Option<mpsc::Receiver<LogEntry>>,
+	api_chan: &'static mut (oneshot::Sender<()>, oneshot::Receiver<()>),
+) {
 	// Run the UI controller.. here for now for simplicity to access
 	// everything it might need
 	if config.run_tui.unwrap_or(false) {
@@ -53,6 +59,8 @@ fn start_server_tui(config: servers::ServerConfig, logs_rx: Option<mpsc::Receive
 				});
 				controller.run(serv);
 			},
+			None,
+			api_chan,
 		)
 		.unwrap();
 	} else {
@@ -73,6 +81,8 @@ fn start_server_tui(config: servers::ServerConfig, logs_rx: Option<mpsc::Receive
 				warn!("Received SIGINT (Ctrl+C) or SIGTERM (kill).");
 				serv.stop();
 			},
+			None,
+			api_chan,
 		)
 		.unwrap();
 	}
@@ -86,6 +96,7 @@ pub fn server_command(
 	server_args: Option<&ArgMatches<'_>>,
 	global_config: GlobalConfig,
 	logs_rx: Option<mpsc::Receiver<LogEntry>>,
+	api_chan: &'static mut (oneshot::Sender<()>, oneshot::Receiver<()>),
 ) -> i32 {
 	// just get defaults from the global config
 	let mut server_config = global_config.members.as_ref().unwrap().server.clone();
@@ -118,7 +129,7 @@ pub fn server_command(
 	if let Some(a) = server_args {
 		match a.subcommand() {
 			("run", _) => {
-				start_server(server_config, logs_rx);
+				start_server(server_config, logs_rx, api_chan);
 			}
 			("", _) => {
 				println!("Subcommand required, use 'grin help server' for details");
@@ -132,7 +143,7 @@ pub fn server_command(
 			}
 		}
 	} else {
-		start_server(server_config, logs_rx);
+		start_server(server_config, logs_rx, api_chan);
 	}
 	0
 }

src/bin/grin.rs

@@ -23,6 +23,7 @@ use crate::config::config::SERVER_CONFIG_FILE_NAME;
 use crate::core::global;
 use crate::util::init_logger;
 use clap::App;
+use futures::channel::oneshot;
 use grin_api as api;
 use grin_chain as chain;
 use grin_config as config;
@@ -127,6 +128,9 @@ fn real_main() -> i32 {
 	let mut logging_config = config.members.as_ref().unwrap().logging.clone().unwrap();
 	logging_config.tui_running = config.members.as_ref().unwrap().server.run_tui;
 
+	let api_chan: &'static mut (oneshot::Sender<()>, oneshot::Receiver<()>) =
+		Box::leak(Box::new(oneshot::channel::<()>()));
+
 	let (logs_tx, logs_rx) = if logging_config.tui_running.unwrap() {
 		let (logs_tx, logs_rx) = mpsc::sync_channel::<LogEntry>(200);
 		(Some(logs_tx), Some(logs_rx))
@@ -177,7 +181,7 @@ fn real_main() -> i32 {
 	match args.subcommand() {
 		// server commands and options
 		("server", Some(server_args)) => {
-			cmd::server_command(Some(server_args), node_config.unwrap(), logs_rx)
+			cmd::server_command(Some(server_args), node_config.unwrap(), logs_rx, api_chan)
 		}
 
 		// client commands and options
@@ -196,6 +200,6 @@ fn real_main() -> i32 {
 		// If nothing is specified, try to just use the config file instead
 		// this could possibly become the way to configure most things
 		// with most command line options being phased out
-		_ => cmd::server_command(None, node_config.unwrap(), logs_rx),
+		_ => cmd::server_command(None, node_config.unwrap(), logs_rx, api_chan),
 	}
 }