fix: surface signal failures and reject non-UTF-8 env files

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "beyond-launch"
-version = "0.3.1"
+version = "0.3.2"
 edition = "2024"
 description = "Analyze a project and detect deployable services, languages, frameworks, commands, and env vars"
 license = "MIT"

src/discovery.rs

@@ -16,8 +16,10 @@ pub fn discover(
     fs: &dyn FileSystem,
 ) -> Result<Discovery, LaunchError> {
     walk(root, &mut signals, fs)?;
-    let outputs = generate(&mut signals, fs);
-    Ok(assemble(outputs, root))
+    let (outputs, warnings) = generate(&mut signals, fs);
+    let mut discovery = assemble(outputs, root);
+    discovery.warnings = warnings;
+    Ok(discovery)
 }
 
 // -- Step 1: Walk + Observe --
@@ -161,21 +163,27 @@ pub fn discover_local_impl(
     fs: &dyn FileSystem,
 ) -> Result<Discovery, LaunchError> {
     walk_local(root, &mut signals)?;
-    let outputs = generate(&mut signals, fs);
-    Ok(assemble(outputs, root))
+    let (outputs, warnings) = generate(&mut signals, fs);
+    let mut discovery = assemble(outputs, root);
+    discovery.warnings = warnings;
+    Ok(discovery)
 }
 
 // -- Step 2: Generate --
 
-pub fn generate(signals: &mut [Box<dyn Signal>], fs: &dyn FileSystem) -> Vec<SignalOutput> {
+pub fn generate(
+    signals: &mut [Box<dyn Signal>],
+    fs: &dyn FileSystem,
+) -> (Vec<SignalOutput>, Vec<String>) {
     let mut outputs = Vec::with_capacity(signals.len());
+    let mut warnings = Vec::new();
     for signal in signals.iter_mut() {
         match signal.generate(fs) {
             Ok(output) => outputs.push(output),
-            Err(e) => eprintln!("signal {} failed: {e}", signal.name()),
+            Err(e) => warnings.push(format!("signal {} failed: {e}", signal.name())),
         }
     }
-    outputs
+    (outputs, warnings)
 }
 
 // -- Step 3: Assemble --
@@ -210,7 +218,7 @@ fn assemble(outputs: Vec<SignalOutput>, root: &Path) -> Discovery {
         }
     }
 
-    Discovery { services, monorepo }
+    Discovery { services, monorepo, ..Default::default() }
 }
 
 /// Get the "dir name" for a path — used for derived name detection.

src/signals/docker_compose.rs

@@ -387,10 +387,11 @@ impl Signal for DockerComposeSignal {
                     for rel in paths {
                         let resolved = compose_dir.join(rel);
                         if let Ok(bytes) = fs.read_file(&resolved) {
-                            let contents = String::from_utf8_lossy(&bytes);
-                            let file_path = resolved.to_string_lossy();
-                            let file_env = parse_env_file_keys(&contents, &file_path);
-                            merge_env_vars(&mut env, &file_env);
+                            if let Ok(contents) = String::from_utf8(bytes) {
+                                let file_path = resolved.to_string_lossy();
+                                let file_env = parse_env_file_keys(&contents, &file_path);
+                                merge_env_vars(&mut env, &file_env);
+                            }
                         }
                     }
                 }

src/types.rs

@@ -15,6 +15,9 @@ pub struct Discovery {
     pub services: Vec<Service>,
     #[serde(skip_serializing_if = "Option::is_none")]
     pub monorepo: Option<Monorepo>,
+    /// Signals that failed during generation; non-empty means the result may be incomplete.
+    #[serde(default, skip_serializing_if = "Vec::is_empty")]
+    pub warnings: Vec<String>,
 }
 
 #[derive(Debug, Clone, Default, Serialize, Deserialize)]