basic tests for SIM client

satrs-example/src/interface/sim_client_udp.rs

@@ -31,7 +31,7 @@ pub fn create_sim_client(sim_request_rx: mpsc::Receiver<SimRequest>) -> Option<S
 }
 
 #[derive(thiserror::Error, Debug)]
-pub enum SimClientCreationResult {
+pub enum SimClientCreationError {
     #[error("io error: {0}")]
     Io(#[from] std::io::Error),
     #[error("timeout when trying to connect to sim UDP server")]
@@ -54,42 +54,51 @@ impl SimClientUdp {
     pub fn new(
         simulator_addr: SocketAddr,
         sim_request_rx: mpsc::Receiver<SimRequest>,
-    ) -> Result<Self, SimClientCreationResult> {
+    ) -> Result<Self, SimClientCreationError> {
         let mut reply_buf: [u8; 4096] = [0; 4096];
-        let udp_client = UdpSocket::bind("127.0.0.1:0")?;
+        let mut udp_client = UdpSocket::bind("127.0.0.1:0")?;
         udp_client.set_read_timeout(Some(Duration::from_millis(100)))?;
+        Self::attempt_connection(&mut udp_client, simulator_addr, &mut reply_buf)?;
+        udp_client.set_nonblocking(true)?;
+        Ok(Self {
+            udp_client,
+            simulator_addr,
+            sim_request_rx,
+            reply_map: SimReplyMap(HashMap::new()),
+            reply_buf,
+        })
+    }
+
+    pub fn attempt_connection(
+        udp_client: &mut UdpSocket,
+        simulator_addr: SocketAddr,
+        reply_buf: &mut [u8],
+    ) -> Result<(), SimClientCreationError> {
         let sim_req = SimRequest::new_with_epoch_time(SimCtrlRequest::Ping);
         let sim_req_json = serde_json::to_string(&sim_req).expect("failed to serialize SimRequest");
         udp_client.send_to(sim_req_json.as_bytes(), simulator_addr)?;
-        match udp_client.recv(&mut reply_buf) {
+        match udp_client.recv(reply_buf) {
             Ok(reply_len) => {
                 let sim_reply: SimReply = serde_json::from_slice(&reply_buf[0..reply_len])?;
                 if sim_reply.component() != SimComponent::SimCtrl {
-                    return Err(SimClientCreationResult::ReplyIsNotPong(sim_reply));
+                    return Err(SimClientCreationError::ReplyIsNotPong(sim_reply));
                 }
-                udp_client.set_read_timeout(None)?;
                 let sim_ctrl_reply =
                     SimCtrlReply::from_sim_message(&sim_reply).expect("invalid SIM reply");
                 match sim_ctrl_reply {
-                    SimCtrlReply::Pong => Ok(Self {
-                        udp_client,
-                        simulator_addr,
-                        sim_request_rx,
-                        reply_map: SimReplyMap(HashMap::new()),
-                        reply_buf,
-                    }),
                     SimCtrlReply::InvalidRequest(_) => {
                         panic!("received invalid request reply from UDP sim server")
                     }
+                    SimCtrlReply::Pong => Ok(()),
                 }
             }
             Err(e) => {
                 if e.kind() == std::io::ErrorKind::TimedOut
                     || e.kind() == std::io::ErrorKind::WouldBlock
                 {
-                    Err(SimClientCreationResult::Timeout)
+                    Err(SimClientCreationError::Timeout)
                 } else {
-                    Err(SimClientCreationResult::Io(e))
+                    Err(SimClientCreationError::Io(e))
                 }
             }
         }
@@ -174,7 +183,238 @@ impl SimClientUdp {
 
 #[cfg(test)]
 pub mod tests {
-    // TODO: Write some basic tests which verify that the ping/pong handling/check for the
+    use std::{
-    // constructor works as expected.
+        collections::HashMap,
-    fn test_basic() {}
+        net::{SocketAddr, UdpSocket},
+        sync::{
+            atomic::{AtomicBool, Ordering},
+            mpsc, Arc,
+        },
+        time::Duration,
+    };
+
+    use satrs_minisim::{
+        eps::{PcduReply, PcduRequest},
+        SerializableSimMsgPayload, SimComponent, SimCtrlReply, SimCtrlRequest, SimMessageProvider,
+        SimReply, SimRequest,
+    };
+
+    use super::SimClientUdp;
+
+    struct UdpSimTestServer {
+        udp_server: UdpSocket,
+        request_tx: mpsc::Sender<SimRequest>,
+        reply_rx: mpsc::Receiver<SimReply>,
+        last_sender: Option<SocketAddr>,
+        stop_signal: Arc<AtomicBool>,
+        recv_buf: [u8; 1024],
+    }
+
+    impl UdpSimTestServer {
+        pub fn new(
+            request_tx: mpsc::Sender<SimRequest>,
+            reply_rx: mpsc::Receiver<SimReply>,
+            stop_signal: Arc<AtomicBool>,
+        ) -> Self {
+            let udp_server = UdpSocket::bind("127.0.0.1:0").expect("creating UDP server failed");
+            udp_server
+                .set_nonblocking(true)
+                .expect("failed to set UDP server to non-blocking");
+            Self {
+                udp_server,
+                request_tx,
+                reply_rx,
+                last_sender: None,
+                stop_signal,
+                recv_buf: [0; 1024],
+            }
+        }
+
+        pub fn operation(&mut self) {
+            loop {
+                let mut no_sim_replies_handled = true;
+                let mut no_data_received = true;
+                if self.stop_signal.load(Ordering::Relaxed) {
+                    break;
+                }
+                if let Some(last_sender) = self.last_sender {
+                    loop {
+                        match self.reply_rx.try_recv() {
+                            Ok(sim_reply) => {
+                                let sim_reply_json = serde_json::to_string(&sim_reply)
+                                    .expect("failed to serialize SimReply");
+                                self.udp_server
+                                    .send_to(sim_reply_json.as_bytes(), last_sender)
+                                    .expect("failed to send reply to client from UDP server");
+                                no_sim_replies_handled = false;
+                            }
+                            Err(e) => match e {
+                                mpsc::TryRecvError::Empty => break,
+                                mpsc::TryRecvError::Disconnected => {
+                                    panic!("reply sender disconnected")
+                                }
+                            },
+                        }
+                    }
+                }
+
+                loop {
+                    match self.udp_server.recv_from(&mut self.recv_buf) {
+                        Ok((read_bytes, from)) => {
+                            let sim_request: SimRequest =
+                                serde_json::from_slice(&self.recv_buf[0..read_bytes])
+                                    .expect("failed to deserialize SimRequest");
+                            if sim_request.component() == SimComponent::SimCtrl {
+                                // For a ping, we perform the reply handling here directly
+                                let sim_ctrl_request =
+                                    SimCtrlRequest::from_sim_message(&sim_request)
+                                        .expect("failed to convert SimRequest to SimCtrlRequest");
+                                match sim_ctrl_request {
+                                    SimCtrlRequest::Ping => {
+                                        no_data_received = false;
+                                        self.last_sender = Some(from);
+                                        let sim_reply = SimReply::new(&SimCtrlReply::Pong);
+                                        let sim_reply_json = serde_json::to_string(&sim_reply)
+                                            .expect("failed to serialize SimReply");
+                                        self.udp_server
+                                            .send_to(sim_reply_json.as_bytes(), from)
+                                            .expect(
+                                                "failed to send reply to client from UDP server",
+                                            );
+                                    }
+                                };
+                            }
+                            // Forward each SIM request for testing purposes.
+                            self.request_tx
+                                .send(sim_request)
+                                .expect("failed to send request");
+                        }
+                        Err(e) => {
+                            if e.kind() != std::io::ErrorKind::WouldBlock
+                                && e.kind() != std::io::ErrorKind::TimedOut
+                            {
+                                panic!("UDP server error: {}", e);
+                            }
+                            break;
+                        }
+                    }
+                }
+                if no_sim_replies_handled && no_data_received {
+                    std::thread::sleep(Duration::from_millis(5));
+                }
+            }
+        }
+
+        pub fn local_addr(&self) -> SocketAddr {
+            self.udp_server.local_addr().unwrap()
+        }
+    }
+
+    #[test]
+    fn basic_connection_test() {
+        let (server_sim_request_tx, server_sim_request_rx) = mpsc::channel();
+        let (_server_sim_reply_tx, server_sim_reply_rx) = mpsc::channel();
+        let stop_signal = Arc::new(AtomicBool::new(false));
+        let mut udp_server = UdpSimTestServer::new(
+            server_sim_request_tx,
+            server_sim_reply_rx,
+            stop_signal.clone(),
+        );
+        let server_addr = udp_server.local_addr();
+        let (_client_sim_req_tx, client_sim_req_rx) = mpsc::channel();
+        // Need to spawn the simulator UDP server before calling the client constructor.
+        let jh0 = std::thread::spawn(move || {
+            udp_server.operation();
+        });
+        // Creating the client also performs the connection test.
+        SimClientUdp::new(server_addr, client_sim_req_rx).unwrap();
+        let sim_request = server_sim_request_rx
+            .recv_timeout(Duration::from_millis(50))
+            .expect("no SIM request received");
+        let ping_request = SimCtrlRequest::from_sim_message(&sim_request)
+            .expect("failed to create SimCtrlRequest");
+        assert_eq!(ping_request, SimCtrlRequest::Ping);
+        // Stop the server.
+        stop_signal.store(true, Ordering::Relaxed);
+        jh0.join().unwrap();
+    }
+
+    #[test]
+    fn basic_request_reply_test() {
+        let (server_sim_request_tx, server_sim_request_rx) = mpsc::channel();
+        let (server_sim_reply_tx, sever_sim_reply_rx) = mpsc::channel();
+        let stop_signal = Arc::new(AtomicBool::new(false));
+        let mut udp_server = UdpSimTestServer::new(
+            server_sim_request_tx,
+            sever_sim_reply_rx,
+            stop_signal.clone(),
+        );
+        let server_addr = udp_server.local_addr();
+        let (client_sim_req_tx, client_sim_req_rx) = mpsc::channel();
+        let (client_pcdu_reply_tx, client_pcdu_reply_rx) = mpsc::channel();
+        // Need to spawn the simulator UDP server before calling the client constructor.
+        let jh0 = std::thread::spawn(move || {
+            udp_server.operation();
+        });
+
+        // Creating the client also performs the connection test.
+        let mut client = SimClientUdp::new(server_addr, client_sim_req_rx).unwrap();
+        client.add_reply_recipient(SimComponent::Pcdu, client_pcdu_reply_tx);
+
+        let sim_request = server_sim_request_rx
+            .recv_timeout(Duration::from_millis(50))
+            .expect("no SIM request received");
+        let ping_request = SimCtrlRequest::from_sim_message(&sim_request)
+            .expect("failed to create SimCtrlRequest");
+        assert_eq!(ping_request, SimCtrlRequest::Ping);
+
+        let pcdu_req = PcduRequest::RequestSwitchInfo;
+        client_sim_req_tx
+            .send(SimRequest::new_with_epoch_time(pcdu_req))
+            .expect("send failed");
+        client.operation();
+
+        // Check that the request arrives properly at the server.
+        let sim_request = server_sim_request_rx
+            .recv_timeout(Duration::from_millis(50))
+            .expect("no SIM request received");
+        let req_recvd_on_server =
+            PcduRequest::from_sim_message(&sim_request).expect("failed to create SimCtrlRequest");
+        matches!(req_recvd_on_server, PcduRequest::RequestSwitchInfo);
+
+        // We inject the reply ourselves.
+        let pcdu_reply = PcduReply::SwitchInfo(HashMap::new());
+        server_sim_reply_tx
+            .send(SimReply::new(&pcdu_reply))
+            .expect("sending PCDU reply failed");
+
+        // Now we verify that the reply is sent by the UDP server back to the client, and then
+        // forwarded by the clients internal map.
+        let mut pcdu_reply_received = false;
+        for _ in 0..3 {
+            client.operation();
+
+            match client_pcdu_reply_rx.try_recv() {
+                Ok(sim_reply) => {
+                    assert_eq!(sim_reply.component(), SimComponent::Pcdu);
+                    let pcdu_reply_from_client = PcduReply::from_sim_message(&sim_reply)
+                        .expect("failed to create PcduReply");
+                    assert_eq!(pcdu_reply_from_client, pcdu_reply);
+                    pcdu_reply_received = true;
+                    break;
+                }
+                Err(e) => match e {
+                    mpsc::TryRecvError::Empty => std::thread::sleep(Duration::from_millis(10)),
+                    mpsc::TryRecvError::Disconnected => panic!("reply sender disconnected"),
+                },
+            }
+        }
+        if !pcdu_reply_received {
+            panic!("no reply received");
+        }
+
+        // Stop the server.
+        stop_signal.store(true, Ordering::Relaxed);
+        jh0.join().unwrap();
+    }
 }

satrs-minisim/src/acs.rs

@@ -153,7 +153,7 @@ impl MagnetorquerModel {
 
     pub fn send_housekeeping_data(&mut self) {
         self.reply_sender
-            .send(SimReply::new(MgtReply::Hk(MgtHkSet {
+            .send(SimReply::new(&MgtReply::Hk(MgtHkSet {
                 dipole: self.torque_dipole,
                 torquing: self.torquing,
             })))

satrs-minisim/src/controller.rs

@@ -102,7 +102,7 @@ impl SimController {
         match sim_ctrl_request {
             SimCtrlRequest::Ping => {
                 self.reply_sender
-                    .send(SimReply::new(SimCtrlReply::Pong))
+                    .send(SimReply::new(&SimCtrlReply::Pong))
                     .expect("sending reply from sim controller failed");
             }
         }
@@ -178,7 +178,7 @@ impl SimController {
             error
         );
         self.reply_sender
-            .send(SimReply::new(SimCtrlReply::from(error)))
+            .send(SimReply::new(&SimCtrlReply::from(error)))
             .expect("sending reply from sim controller failed");
     }
 }

satrs-minisim/src/eps.rs

@@ -44,7 +44,7 @@ impl PcduModel {
     }
 
     pub fn send_switch_info(&mut self) {
-        let reply = SimReply::new(PcduReply::SwitchInfo(self.switcher_map.clone()));
+        let reply = SimReply::new(&PcduReply::SwitchInfo(self.switcher_map.clone()));
         self.reply_sender.send(reply).unwrap();
     }
 

satrs-minisim/src/lib.rs

@@ -96,11 +96,11 @@ pub struct SimReply {
 }
 
 impl SimReply {
-    pub fn new<T: SerializableSimMsgPayload<SimReply>>(serializable_reply: T) -> Self {
+    pub fn new<T: SerializableSimMsgPayload<SimReply>>(serializable_reply: &T) -> Self {
         Self {
             inner: SimMessage {
                 target: T::TARGET,
-                payload: serde_json::to_string(&serializable_reply).unwrap(),
+                payload: serde_json::to_string(serializable_reply).unwrap(),
             },
         }
     }
@@ -185,7 +185,7 @@ pub mod eps {
         const TARGET: SimComponent = SimComponent::Pcdu;
     }
 
-    #[derive(Debug, Clone, Serialize, Deserialize)]
+    #[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
     pub enum PcduReply {
         SwitchInfo(SwitchMap),
     }
@@ -295,7 +295,7 @@ pub mod acs {
 
         impl MgmReplyProvider for MgmLis3MdlReply {
             fn create_mgm_reply(common: MgmReplyCommon) -> SimReply {
-                SimReply::new(Self::new(common))
+                SimReply::new(&Self::new(common))
             }
         }
     }
@@ -382,7 +382,7 @@ pub mod tests {
 
     #[test]
     fn test_basic_reply() {
-        let sim_reply = SimReply::new(DummyReply::Pong);
+        let sim_reply = SimReply::new(&DummyReply::Pong);
         assert_eq!(sim_reply.component(), SimComponent::SimCtrl);
         assert_eq!(sim_reply.msg_type(), SimMessageType::Reply);
         let dummy_request =

satrs-minisim/src/udp.rs

@@ -344,7 +344,7 @@ mod tests {
             .send_request(&SimRequest::new_with_epoch_time(SimCtrlRequest::Ping))
             .expect("sending request failed");
 
-        let sim_reply = SimReply::new(PcduReply::SwitchInfo(get_all_off_switch_map()));
+        let sim_reply = SimReply::new(&PcduReply::SwitchInfo(get_all_off_switch_map()));
         udp_testbench.send_reply(&sim_reply);
 
         udp_testbench.check_next_sim_reply(&sim_reply);
@@ -369,7 +369,7 @@ mod tests {
             .expect("sending request failed");
 
         // Send a reply to the server, ensure it gets forwarded to the client.
-        let sim_reply = SimReply::new(PcduReply::SwitchInfo(get_all_off_switch_map()));
+        let sim_reply = SimReply::new(&PcduReply::SwitchInfo(get_all_off_switch_map()));
         udp_testbench.send_reply(&sim_reply);
         std::thread::sleep(Duration::from_millis(SERVER_WAIT_TIME_MS));
 
@@ -388,7 +388,7 @@ mod tests {
         let server_thread = std::thread::spawn(move || udp_server.run());
 
         // Send a reply to the server. The client is not connected, so it won't get forwarded.
-        let sim_reply = SimReply::new(PcduReply::SwitchInfo(get_all_off_switch_map()));
+        let sim_reply = SimReply::new(&PcduReply::SwitchInfo(get_all_off_switch_map()));
         udp_testbench.send_reply(&sim_reply);
         std::thread::sleep(Duration::from_millis(10));
 
@@ -415,7 +415,7 @@ mod tests {
         let server_thread = std::thread::spawn(move || udp_server.run());
 
         // The server only caches up to 3 replies.
-        let sim_reply = SimReply::new(SimCtrlReply::Pong);
+        let sim_reply = SimReply::new(&SimCtrlReply::Pong);
         for _ in 0..4 {
             udp_testbench.send_reply(&sim_reply);
         }