First test kinda working

simulator/tests/end_to_end_t1.rs

@@ -0,0 +1,139 @@
+//! End-to-end T1 datagram test: spin up substrate's listener in-process with
+//! channels the test owns, drive a `SimulatorClient` against it, and assert
+//! the datagram lands in the T1 receiver decoded.
+//!
+//! Run with `cargo test -p simulator`.
+
+use std::net::SocketAddr;
+use std::path::PathBuf;
+use std::time::Duration;
+
+use anyhow::Result;
+use simulator::client::SimulatorClient;
+use substrate::config::QuicConfig;
+use substrate::transport::server::{accept_loop, bind_endpoint};
+use substrate::transport::{QuicMessage, SensorType, T1Sender, T2Sender, T3Sender};
+use tokio::sync::mpsc;
+use uuid::Uuid;
+
+fn cert_path(name: &str) -> PathBuf {
+    [env!("CARGO_MANIFEST_DIR"), "..", "certs", name].iter().collect()
+}
+
+fn loopback_config(cert: PathBuf, key: PathBuf) -> QuicConfig {
+    QuicConfig {
+        // Port 0 lets the OS pick a free ephemeral port — tests can run in
+        // parallel without colliding on a fixed bind.
+        server_port: 0,
+        server_interface: "127.0.0.1".to_string(),
+        server_cert: cert.to_string_lossy().into_owned(),
+        server_key: key.to_string_lossy().into_owned(),
+    }
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn t1_datagram_decoded_into_ecs_channel() -> Result<()> {
+    simulator::install_crypto_provider();
+
+    let cert = cert_path("server.crt");
+    let key = cert_path("server.key");
+    let cfg = loopback_config(cert.clone(), key);
+
+    // Bind the substrate's listener on an ephemeral port.
+    let endpoint = bind_endpoint(&cfg)?;
+    let server_addr: SocketAddr = endpoint.local_addr()?;
+
+    // Channels the test owns — gives us direct visibility into what the T1
+    // demux pushes into the ECS bridge.
+    let (t1_tx, mut t1_rx) = mpsc::channel(64);
+    let (t2_tx, _t2_rx) = mpsc::channel(64);
+    let (t3_tx, _t3_rx) = mpsc::channel(64);
+
+    let server_task = tokio::spawn(accept_loop(
+        endpoint,
+        T1Sender::new(t1_tx),
+        T2Sender::new(t2_tx),
+        T3Sender::new(t3_tx),
+    ));
+
+    // Connect a client and send one datagram.
+    let client = SimulatorClient::connect(server_addr, "localhost", &cert).await?;
+
+    let sent = QuicMessage {
+        device_id: Uuid::from_u128(0xdead_beef_cafe_f00d_1234_5678_90ab_cdef),
+        sensor_id: 7,
+        raw_value: 42.0,
+        timestamp_us: 1_700_000_000_000_001,
+        sequence_number: 1,
+        sensor_type: SensorType::Temperature.as_u8(),
+    };
+    client.send_datagram(&sent)?;
+
+    // Wait for the substrate's read_datagrams reader to push it into T1.
+    let received = tokio::time::timeout(Duration::from_secs(2), t1_rx.recv())
+        .await
+        .expect("did not observe T1 datagram within 2s")
+        .expect("T1 channel closed unexpectedly");
+
+    assert_eq!(received, sent);
+
+    client.close().await;
+    server_task.abort();
+    Ok(())
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn t1_burst_preserves_order_and_count() -> Result<()> {
+    simulator::install_crypto_provider();
+
+    let cert = cert_path("server.crt");
+    let key = cert_path("server.key");
+    let cfg = loopback_config(cert.clone(), key);
+
+    let endpoint = bind_endpoint(&cfg)?;
+    let server_addr: SocketAddr = endpoint.local_addr()?;
+
+    // T1 capacity 64 ≥ burst size 32 so nothing is dropped under loopback.
+    let (t1_tx, mut t1_rx) = mpsc::channel(64);
+    let (t2_tx, _t2_rx) = mpsc::channel(8);
+    let (t3_tx, _t3_rx) = mpsc::channel(8);
+
+    let server_task = tokio::spawn(accept_loop(
+        endpoint,
+        T1Sender::new(t1_tx),
+        T2Sender::new(t2_tx),
+        T3Sender::new(t3_tx),
+    ));
+
+    let client = SimulatorClient::connect(server_addr, "localhost", &cert).await?;
+
+    let device = Uuid::from_u128(0xa1a2_a3a4_b5b6_b7b8_c9ca_cbcc_cdce_cfd0);
+    const BURST: u32 = 32;
+    for seq in 0..BURST {
+        let msg = QuicMessage {
+            device_id: device,
+            sensor_id: 0,
+            raw_value: f64::from(seq),
+            timestamp_us: 1_700_000_000_000_000 + u64::from(seq),
+            sequence_number: seq,
+            sensor_type: SensorType::Generic.as_u8(),
+        };
+        client.send_datagram(&msg)?;
+    }
+
+    // Drain BURST messages with a per-message timeout. Loopback shouldn't
+    // reorder QUIC datagrams within a single connection.
+    for expected_seq in 0..BURST {
+        let msg = tokio::time::timeout(Duration::from_secs(2), t1_rx.recv())
+            .await
+            .unwrap_or_else(|_| panic!("missed datagram seq={expected_seq}"))
+            .expect("T1 channel closed");
+        assert_eq!(msg.sequence_number, expected_seq);
+        assert_eq!(msg.device_id, device);
+        assert_eq!(msg.raw_value, f64::from(expected_seq));
+    }
+
+    client.close().await;
+    server_task.abort();
+    Ok(())
+}