in functions_framework/lib/src/run.dart [21:38]
Future<void> run(
int port,
Handler handler,
Future<bool> shutdownSignal,
Middleware loggingMiddleware,
) async {
final server = await shelf_io.serve(
loggingMiddleware
.addMiddleware(_forbiddenAssetMiddleware)
.addHandler(handler),
InternetAddress.anyIPv4,
port,
);
print('Listening on :${server.port}');
final force = await shutdownSignal;
await server.close(force: force);
}