NDT7 Dart Proof of Concept

import 'dart:io';
import 'dart:convert';
import 'dart:math';
import 'dart:typed_data';

import 'package:http/http.dart' as http;

// Upload

// 1MB
const MaxUploadSize = 1 << 20;
// 8KB
const InitUploadSize = 1 << 13;

var bytesSoFar = 0;
var lastMessageSize = InitUploadSize;
Uint8List randomMessage = Uint8List(MaxUploadSize);

Stream<Uint8List> uploadMessageStream() async* {
  var rand = Random();
  for (var i = 0; i < MaxUploadSize; i++) {
    randomMessage[i] = rand.nextInt(256);
  }

  while (true) {
    if (lastMessageSize >= MaxUploadSize ||
        lastMessageSize >= (bytesSoFar / 16)) {
      bytesSoFar += lastMessageSize;
      yield randomMessage.sublist(0, lastMessageSize);
    } else {
      var nextMessageSize = lastMessageSize * 2;
      lastMessageSize = nextMessageSize;
      bytesSoFar += nextMessageSize;
      yield randomMessage.sublist(0, nextMessageSize);
    }
  }
}

Uint8List nextUploadMessage() {
  if (bytesSoFar == 0) {
    var rand = Random();
    for (var i = 0; i < MaxUploadSize; i++) {
      randomMessage[i] = rand.nextInt(256);
    }
  }

  if (lastMessageSize >= MaxUploadSize ||
      lastMessageSize >= (bytesSoFar / 16)) {
    bytesSoFar += lastMessageSize;
    return randomMessage.sublist(0, lastMessageSize);
  } else {
    var nextMessageSize = lastMessageSize * 2;
    lastMessageSize = nextMessageSize;
    bytesSoFar += nextMessageSize;
    return randomMessage.sublist(0, nextMessageSize);
  }
}

upload(String url) async {
  final socket =
      await WebSocket.connect(url, protocols: ['net.measurementlab.ndt.v7']);
  DateTime startTime = DateTime.now();
  socket.listen(
    (event) {
      print("here");
      if (event is String) {
        print(event);
      } else {
        print("Unexpected type while uploading: ${event.runtimeType}");
      }
    },
    onDone: () {
      DateTime endTime = DateTime.now();
      var took = endTime.difference(startTime);
      print("Took ${took}");
    },
    onError: (error) => print(error),
    cancelOnError: false,
  );

  //while (socket.closeCode == null) {
  //var message = nextUploadMessage();
  //socket.add(message);
  //print(socket.length);
  var stream = uploadMessageStream();
  socket.addStream(stream);
  //}
}

// Download

download(String url) async {
  DateTime startTime = DateTime.now();
  final socket =
      await WebSocket.connect(url, protocols: ['net.measurementlab.ndt.v7']);
  socket.listen(
    (event) {
      if (event is Uint8List) {
      } else if (event is String) {
        //print(event);
      } else {
        //print(event.runtimeType);
      }
    },
    onDone: () {
      DateTime endTime = DateTime.now();
      var took = endTime.difference(startTime);
      print("Took ${took}");
    },
    onError: (error) => print(error),
    cancelOnError: false,
  );
}

Future<List<String>> locate() async {
  var client = http.Client();

  var url = Uri.parse(
      'https://locate.measurementlab.net/v2/nearest/ndt/ndt7?client_name=dart-client&client_library_name=ndt7-dart&client_library_version=0.0.1');
  var rawResponse = await client.get(url);
  print(rawResponse.body);
  print('Response status: ${rawResponse.statusCode}');
  var response = jsonDecode(rawResponse.body);

  var downloadUrl = response['results'][0]['urls']['ws:///ndt/v7/download'];
  var uploadUrl = response['results'][0]['urls']['ws:///ndt/v7/upload'];

  return [downloadUrl, uploadUrl];
}

void main() async {
  var results = await locate();
  await download(results[0]);
  await upload(results[1]);
}