waitForVmServiceInfoFile method

Future<Uri> waitForVmServiceInfoFile(Logger? logger, File vmServiceInfoFile)

Waits for vmServiceInfoFile to exist and become valid before returning the VM Service URI contained within.

Implementation

Future<Uri> waitForVmServiceInfoFile(
  Logger? logger,
  File vmServiceInfoFile,
) async {
  final completer = Completer<Uri>();
  late final StreamSubscription<FileSystemEvent> vmServiceInfoFileWatcher;

  void tryParseServiceInfoFile(FileSystemEvent event) {
    final uri = _readVmServiceInfoFile(logger, vmServiceInfoFile);
    if (uri != null && !completer.isCompleted) {
      vmServiceInfoFileWatcher.cancel();
      completer.complete(uri);
    }
  }

  vmServiceInfoFileWatcher = vmServiceInfoFile.parent
      .watch(events: FileSystemEvent.all)
      .where((event) => event.path == vmServiceInfoFile.path)
      .listen(
        tryParseServiceInfoFile,
        onError: (e) => logger?.call('Ignoring exception from watcher: $e'),
      );

  // After setting up the watcher, also check if the file already exists to
  // ensure we don't miss it if it was created right before we set the
  // watched up.
  final uri = _readVmServiceInfoFile(logger, vmServiceInfoFile);
  if (uri != null && !completer.isCompleted) {
    unawaited(vmServiceInfoFileWatcher.cancel());
    completer.complete(uri);
  }

  return completer.future;
}