Dart Shelf Post Request No Body Data

Question

I am building a simple API using Dart Shelf. The GET requests work fine but I can't seem to be able to access the request body for a POST request.

import 'dart:io' show InternetAddress;

import 'package:shelf/shelf.dart' show Request, Response;
import 'package:shelf/shelf_io.dart' show serve;
import 'package:shelf_router/shelf_router.dart' show Router;

void main() async {

    Router router = Router();

    router.get('/', (Request request) {
        return Response.ok('this is the base URL');
    });

    router.post('/accounts', (Request request) async{
        final body = await request.readAsString();
        print(body);
        return Response.ok(body);
    });

    final server = await serve(
        router,
        InternetAddress.anyIPv4,
        8080,
    );

    print('Serving at http://${server.address.host}:${server.port}');
}

When I make the request I get the 200 OK status code but where is the body data?