feat(standalone-daemon): pass configuration with -c CLI option (#244)

Although the option was present, the daemon did not actually read and
process the configuration file.

This commit introduces this feature, which allows loading extensions and
paves the way for nodes written in other programming languages.

* zenoh-flow-standalone-daemon/src/main.rs: read the configuration file
  pointed at by the provided path.

Signed-off-by: Julien Loudet <julien.loudet@zettascale.tech>

zenoh-flow-standalone-daemon/src/main.rs

@@ -58,22 +58,6 @@ async fn main() {
         return;
     }
 
-    let runtime_builder = match cli.configuration {
-        Some(path) => {
-            let (zenoh_flow_configuration, _) =
-                try_parse_from_file::<ZenohFlowConfiguration>(&path, Vars::default())
-                    .unwrap_or_else(|e| {
-                        panic!(
-                            "Failed to parse a Zenoh-Flow Configuration from < {} >:\n{e:?}",
-                            path.display()
-                        )
-                    });
-
-            Runtime::builder(zenoh_flow_configuration.name)
-        }
-        None => Runtime::builder(cli.name.unwrap()),
-    };
-
     let zenoh_config = match cli.zenoh_configuration {
         Some(path) => zenoh::prelude::Config::from_file(path.clone()).unwrap_or_else(|e| {
             panic!(
@@ -90,15 +74,31 @@ async fn main() {
         .unwrap_or_else(|e| panic!("Failed to open Zenoh session:\n{e:?}"))
         .into_arc();
 
-    let runtime = runtime_builder
-        .session(zenoh_session)
-        .build()
-        .await
-        .expect("Failed to build the Zenoh-Flow Runtime");
+    let daemon = match cli.configuration {
+        Some(path) => {
+            let (zenoh_flow_configuration, _) =
+                try_parse_from_file::<ZenohFlowConfiguration>(&path, Vars::default())
+                    .unwrap_or_else(|e| {
+                        panic!(
+                            "Failed to parse a Zenoh-Flow Configuration from < {} >:\n{e:?}",
+                            path.display()
+                        )
+                    });
 
-    let daemon = Daemon::spawn(runtime)
+            Daemon::spawn_from_config(zenoh_session, zenoh_flow_configuration)
+                .await
+                .expect("Failed to spawn the Zenoh-Flow Daemon")
+        }
+        None => Daemon::spawn(
+            Runtime::builder(cli.name.unwrap())
+                .session(zenoh_session)
+                .build()
+                .await
+                .expect("Failed to build the Zenoh-Flow Runtime"),
+        )
         .await
-        .expect("Failed to spawn the Zenoh-Flow Daemon");
+        .expect("Failed to spawn the Zenoh-Flow Daemon"),
+    };
 
     async_std::task::spawn(async move {
         let mut signals = Signals::new([SIGTERM, SIGINT, SIGQUIT])
@@ -112,8 +112,8 @@ async fn main() {
                     break;
                 }
 
-                _ => {
-                    unreachable!()
+                signal => {
+                    tracing::warn!("Ignoring signal ({signal})");
                 }
             }
         }