run regression test with local docker image instead of actual server

xtask/src/main.rs

@@ -144,10 +144,18 @@ fn vs_production() -> Result<(), DynError> {
 
 fn regression() -> Result<(), DynError> {
     let mut snake = run_snake(8000, Some("error"))?;
+    let mut prod = match run_production(8001) {
+        Ok(prod) => prod,
+        err => {
+            snake.kill()?;
+            err?;
+            unreachable!()
+        }
+    };
 
     let res = try_regression();
 
-    snake.kill()?;
+    snake.kill().and(prod.kill())?;
     let (won, games) = res?;
     println!(
         "\nThe local snake has won {won}/{games} games ({}%)",
@@ -157,10 +165,10 @@ fn regression() -> Result<(), DynError> {
 }
 
 fn try_regression() -> Result<(usize, usize), DynError> {
-    const GAMES: usize = 1000;
+    const GAMES: usize = 100;
-    // use only 4 threads so we don't ddos the server
+    // limit the parallelism
     rayon::ThreadPoolBuilder::new()
-        .num_threads(4)
+        .num_threads(std::thread::available_parallelism()?.get() / 3)
         .build_global()
         .unwrap();
 
@@ -168,7 +176,6 @@ fn try_regression() -> Result<(usize, usize), DynError> {
         .into_par_iter()
         .map(|_| -> Option<usize> {
             eprint!(".");
-            // let _ = stderr().flush();
             let game = Command::new("./battlesnake-cli")
                 .current_dir(project_root())
                 .args([
@@ -184,7 +191,7 @@ fn try_regression() -> Result<(usize, usize), DynError> {
                     "--name",
                     "production",
                     "--url",
-                    "https://snake.mkaenner.de",
+                    "http://localhost:8001",
                     "-g",
                     "duel",
                 ])
@@ -235,6 +242,30 @@ fn run_snake(port: u16, log: Option<&str>) -> Result<Child, DynError> {
     }
 }
 
+fn run_production(port: u16) -> Result<Child, DynError> {
+    let mut snake = Command::new("docker")
+        .args([
+            "run",
+            "--env",
+            "RUST_LOG=error",
+            "--env",
+            format!("ROCKET_PORT={}", port).as_str(),
+            "--network=host",
+            "-i",
+            "docker.mkaenner.de/snake:latest",
+        ])
+        .spawn()?;
+    loop {
+        if let Some(status) = snake.try_wait()? {
+            Err(format!("{status}"))?;
+        }
+        if TcpStream::connect(("127.0.0.1", port)).is_ok() {
+            break Ok(snake);
+        }
+        sleep(Duration::from_secs(1));
+    }
+}
+
 fn docker() -> Result<(), DynError> {
     if !Command::new("docker")
         .current_dir(project_root())