Add JSON config support for device USB port mappings

bin/rover.dart

@@ -8,6 +8,7 @@ void main(List<String> cliArgs) async {
   final parser = ArgParser();
   final programNames = { for (final program in programs) program.name };
   parser.addOption("only", help: "Only compile the given program", allowed: programNames);
+  parser.addOption("config", help: "Path to JSON config file for device mappings");
   parser.addFlag("compile", help: "Compile all rover programs", defaultsTo: true);
   parser.addFlag("udev", help: "Generate udev rules", defaultsTo: true);
   parser.addFlag("offline", help: "Skip any steps that require internet", negatable: false);
@@ -21,11 +22,12 @@ void main(List<String> cliArgs) async {
   final udev = args.flag("udev");
   final compile = args.flag("compile");
   final only = args.option("only");
+  final configPath = args.option("config");
   Logger.level = verbose ? LogLevel.all : LogLevel.info;
 
   if (showHelp) {
     // ignore: avoid_print
-    print("\nUsage: dart run :rover [--offline] [--verbose] [--only <program>] [--help]\n${parser.usage}");
+    print("\nUsage: dart run :rover [--offline] [--verbose] [--only <program>] [--config <path>] [--help]\n${parser.usage}");
     return;
   }
 
@@ -35,7 +37,7 @@ void main(List<String> cliArgs) async {
 
   if (udev) {
     logger.info("Generating udev rules...");
-    await writeUdevFile();
+    await writeUdevFile(configPath: configPath);
   }
 
   logger.info("Done!");

camera_config.example.json

@@ -0,0 +1,51 @@
+{
+  "devices": [
+    {
+      "humanName": "Front Camera",
+      "alias": "rover_cam_front",
+      "type": "camera",
+      "port": "3-2:1.0",
+      "index": 0
+    },
+    {
+      "humanName": "Rear Camera",
+      "alias": "rover_cam_rear",
+      "type": "camera",
+      "port": "1-2.4:1.0",
+      "index": 0
+    },
+    {
+      "humanName": "Bottom Left Camera",
+      "alias": "rover_cam_bottom_left",
+      "type": "camera",
+      "port": "1-2.3:1.0",
+      "index": 0
+    },
+    {
+      "humanName": "Bottom Right Camera",
+      "alias": "rover_cam_bottom_right",
+      "type": "camera",
+      "port": "1-2.2:1.0",
+      "index": 0
+    },
+    {
+      "humanName": "RealSense RGB",
+      "alias": "rover_realsense_rgb",
+      "type": "camera",
+      "interface": "Intel(R) RealSense(TM) Depth Camera 435i RGB",
+      "index": 0
+    },
+    {
+      "humanName": "GPS",
+      "alias": "rover_gps",
+      "type": "serial",
+      "manufacturer": "u-blox AG - www.u-blox.com"
+    },
+    {
+      "humanName": "IMU",
+      "alias": "rover_imu",
+      "type": "serial",
+      "product": "CDC + MSD Demo"
+    }
+  ]
+}

lib/src/device.dart

@@ -1,3 +1,5 @@
+import "package:burt_network/burt_network.dart";
+
 /// The type of USB-device, which determines what subsystem it is.
 enum DeviceType {
   /// A camera.
@@ -59,4 +61,30 @@ class Device {
     this.interface,
     this.serialNumber,
   });
+
+  /// Creates a USB device from a JSON configuration.
+  factory Device.fromJson(Json json) => Device(
+    humanName: json["humanName"] as String,
+    alias: json["alias"] as String,
+    type: DeviceType.values.byName(json["type"] as String),
+    manufacturer: json["manufacturer"] as String?,
+    product: json["product"] as String?,
+    index: json["index"] as int?,
+    port: json["port"] as String?,
+    interface: json["interface"] as String?,
+    serialNumber: json["serialNumber"] as String?,
+  );
+
+  /// Converts this device to a JSON map.
+  Json toJson() => {
+    "humanName": humanName,
+    "alias": alias,
+    "type": type.name,
+    if (manufacturer != null) "manufacturer": manufacturer,
+    if (product != null) "product": product,
+    if (index != null) "index": index,
+    if (port != null) "port": port,
+    if (interface != null) "interface": interface,
+    if (serialNumber != null) "serialNumber": serialNumber,
+  };
 }

lib/src/utils.dart

@@ -1,6 +1,7 @@
+import "dart:convert";
 import "dart:io";
 
-import "package:burt_network/logging.dart";
+import "package:burt_network/burt_network.dart" hide Device;
 import "package:rover/rover.dart";
 
 /// The logger for all scripts.
@@ -65,10 +66,41 @@ Future<void> writeSystemdFile(RoverProgram program) async {
 }
 
 /// Writes a udev rules file to `/etc/udev/rules.d` with all devices at once.
-Future<void> writeUdevFile() async {
+Future<void> writeUdevFile({String? configPath}) async {
+  // Load devices from config or use defaults
+  var deviceList = devices;
+
+  if (configPath != null) {
+    logger.info("Loading device config from $configPath");
+    final configFile = File(configPath);
+    if (!configFile.existsSync()) {
+      logger.error("Config file not found: $configPath");
+      exit(1);
+    }
+
+    try {
+      final configContent = await configFile.readAsString();
+      final configJson = jsonDecode(configContent) as Json;
+      final devicesJson = configJson["devices"] as List<dynamic>;
+
+      deviceList = [
+        for (final json in devicesJson)
+          Device.fromJson(json as Json),
+      ];
+
+      logger.info("Loaded ${deviceList.length} devices from config");
+    } on FormatException catch (error) {
+      logger.error("Invalid JSON in config file: $error");
+      exit(1);
+    } catch (error) {
+      logger.error("Failed to parse config file: $error");
+      exit(1);
+    }
+  }
+
   final buffer = StringBuffer();
   buffer.writeln(udevHeader);
-  for (final device in devices) {
+  for (final device in deviceList) {
     logger.debug("Generating udev rules for ${device.humanName}");
     final rule = device.udevRule;
     logger.trace(rule);
@@ -84,5 +116,5 @@ Future<void> writeUdevFile() async {
   await runCommand("sudo", ["udevadm", "control", "--reload-rules"]);
   await runCommand("sudo", ["udevadm", "trigger"]);
   await udevFile.delete();
-  logger.debug("Generated udev rules with ${devices.length} devices");
+  logger.debug("Generated udev rules with ${deviceList.length} devices");
 }