Merge pull request #279 from kerberos-io/fix/block-config-endpoint-on-brokenstream

fix/block-config-endpoint-on-brokenstream

machinery/src/components/Kerberos.go

@@ -752,10 +752,24 @@ func GetSnapshotRaw(c *gin.Context, captureDevice *capture.Capture, configuratio
 // @Description Get the current configuration.
 // @Success 200
 func GetConfig(c *gin.Context, captureDevice *capture.Capture, configuration *models.Configuration, communication *models.Communication) {
-	// We'll try to get a snapshot from the camera.
-	base64Image := capture.Base64Image(captureDevice, communication, configuration)
-	if base64Image != "" {
-		communication.Image = base64Image
+	// We'll try to get a fresh snapshot from the camera. Capturing a snapshot
+	// reads a keyframe from the live stream, which blocks until one arrives.
+	// When the camera is offline or the stream is stalled (no packets being
+	// received) this would block the /config endpoint indefinitely, making the
+	// agent appear unreachable even though its HTTP server is healthy. We
+	// therefore bound the snapshot fetch with a short timeout and fall back to
+	// the last cached snapshot, so /config always responds promptly.
+	snapshot := make(chan string, 1)
+	go func() {
+		snapshot <- capture.Base64Image(captureDevice, communication, configuration)
+	}()
+	select {
+	case base64Image := <-snapshot:
+		if base64Image != "" {
+			communication.Image = base64Image
+		}
+	case <-time.After(2 * time.Second):
+		log.Log.Info("components.Kerberos.GetConfig(): snapshot timed out (stream stalled or camera offline), returning configuration with the last cached snapshot.")
 	}
 
 	c.JSON(200, gin.H{

machinery/src/config/main.go

@@ -215,7 +215,18 @@ func OverrideWithEnvironmentVariables(configuration *models.Configuration) {
 		configuration.GlobalConfig = globalWrap.Config
 
 		// Parse the per-agent (custom) configuration from the AGENT_* variables.
-		customWrap := &models.Configuration{Config: configuration.CustomConfig}
+		// In ConfigMap mode the per-agent overrides are delivered exclusively
+		// through AGENT_* environment variables, so we must start from an empty
+		// configuration rather than the bundled config.json that OpenConfig loaded
+		// into CustomConfig. Otherwise defaults from that file (e.g. cloud="s3")
+		// would leak into the custom config and be mistaken for explicit per-agent
+		// overrides, hiding inherited global settings (the factory edit page would
+		// show the local default instead of the inherited global persistence).
+		customBase := configuration.CustomConfig
+		if isConfigMapMode() {
+			customBase = models.Config{}
+		}
+		customWrap := &models.Configuration{Config: customBase}
 		initConfigPointers(&customWrap.Config)
 		applyAgentEnvVars(customWrap, "", false)
 		configuration.CustomConfig = customWrap.Config
@@ -233,6 +244,21 @@ func OverrideWithEnvironmentVariables(configuration *models.Configuration) {
 	}
 }
 
+// isConfigMapMode reports whether the agent is running in ConfigMap mode, i.e.
+// whether a global configuration layer is delivered separately through
+// GLOBAL_AGENT_* environment variables. In that mode the per-agent (custom)
+// configuration must be built solely from the AGENT_* overrides and must not be
+// seeded with the bundled config.json defaults, so that inherited global
+// settings remain distinguishable from explicit per-agent overrides.
+func isConfigMapMode() bool {
+	for _, env := range os.Environ() {
+		if strings.HasPrefix(env, "GLOBAL_AGENT_") {
+			return true
+		}
+	}
+	return false
+}
+
 // initConfigPointers ensures all pointer sub-structs are non-nil so that the
 // environment-variable parsing can assign into them without dereferencing a nil
 // pointer.