Added until_termination.

Author: horned-sphere

server/swimos_server_app/Cargo.toml

@@ -5,9 +5,10 @@ authors = ["Swim Inc. developers info@swim.ai"]
 edition = "2021"
 
 [features]
-default = []
+default = ["signal"]
 rocks_store = ["swimos_rocks_store"]
 trust_dns = ["swimos_runtime/trust_dns"]
+signal = ["tokio/signal"]
 
 [dependencies]
 futures = { workspace = true }

server/swimos_server_app/src/lib.rs

@@ -65,6 +65,9 @@ pub use self::{
     util::AgentExt,
 };
 
+#[cfg(feature = "signal")]
+pub use server::wait::{until_termination, RegistrationFailed};
+
 pub use error::{AmbiguousRoutes, ServerBuilderError, ServerError};
 pub use ratchet::deflate::{DeflateConfig, WindowBits};
 pub use swimos_introspection::IntrospectionConfig;

server/swimos_server_app/src/server/mod.rs

@@ -126,3 +126,57 @@ impl Server for BoxServer {
         self.0.run_box()
     }
 }
+
+#[cfg(feature = "signal")]
+pub mod wait {
+    use std::net::SocketAddr;
+
+    use tracing::debug;
+
+    use crate::ServerHandle;
+
+    use thiserror::Error;
+
+    /// Errors that can occur waiting for tha server to stop.
+    #[derive(Debug, Error, Clone, Copy)]
+    #[error("The Ctrl-C handler could not be installed.")]
+    pub struct RegistrationFailed;
+
+    /// Register a Ctrl-C handler that will stop a server instance.
+    ///
+    /// # Arguments
+    /// * `server` - The server to run.
+    /// * `bound` - If specified this will be called when the server has bound to a socket, with the address.
+    pub async fn start_and_await(
+        mut handle: ServerHandle,
+        bound: Option<Box<dyn FnOnce(SocketAddr) + Send>>,
+    ) -> Result<(), RegistrationFailed> {
+        
+        let wait_for_ctrl_c = async move {
+            let mut result = Ok(());
+            let mut shutdown_hook = Box::pin(async { tokio::signal::ctrl_c().await });
+
+            let print_addr = handle.bound_addr();
+
+            let maybe_addr = tokio::select! {
+                r = &mut shutdown_hook => {
+                    result = r;
+                    None
+                },
+                maybe_addr = print_addr => maybe_addr,
+            };
+
+            if let Some(addr) = maybe_addr {
+                if let Some(f) = bound {
+                    f(addr);
+                }
+                result = shutdown_hook.await;
+            }
+
+            debug!("Stopping server.");
+            handle.stop();
+            result
+        };
+        wait_for_ctrl_c.await.map_err(|_| RegistrationFailed)
+    }
+}

swimos/Cargo.toml

@@ -16,7 +16,7 @@ swimos_utilities = { path = "../swimos_utilities", features = ["io", "text"] }
 swimos_api = { path = "../api/swimos_api" }
 swimos_model = { path = "../api/swimos_model" }
 swimos_recon = { path = "../api/formats/swimos_recon" }
-swimos_server_app = { path = "../server/swimos_server_app", optional = true }
+swimos_server_app = { path = "../server/swimos_server_app", optional = true, features = ["signal"]}
 swimos_agent = { path = "../server/swimos_agent", optional = true }
 swimos_agent_derive = { path = "../server/swimos_agent_derive", optional = true }
 swimos_remote = { path = "../runtime/swimos_remote", optional = true}

swimos/src/lib.rs

@@ -94,8 +94,8 @@ pub mod io {
 #[cfg(feature = "server")]
 pub mod server {
     pub use swimos_server_app::{
-        BoxServer, DeflateConfig, IntrospectionConfig, RemoteConnectionsConfig, Server,
-        ServerBuilder, ServerHandle, WindowBits,
+        start_and_await, BoxServer, DeflateConfig, IntrospectionConfig, RemoteConnectionsConfig,
+        Server, ServerBuilder, ServerHandle, WindowBits,
     };
 
     /// Configuration for TLS support in the server.
@@ -111,7 +111,7 @@ pub mod server {
         pub use swimos_remote::tls::TlsError;
         pub use swimos_remote::ConnectionError;
         pub use swimos_server_app::{
-            AmbiguousRoutes, ServerBuilderError, ServerError, UnresolvableRoute,
+            AmbiguousRoutes, RegistrationFailed, ServerBuilderError, ServerError, UnresolvableRoute,
         };
     }
 }