Dart: handle incoming HTTP requests in parallel

Question

I am trying to write an HTTP server in Dart that can handle multiple requests in parallel. I have been unsuccessful at achieving the \"parallel\" part thus far.

Her

Answer 1

You need to:

1. Set shared: true in HttpServer.bind
2. Spawn some Isolates to handle the incoming requests in parallel.

Here's a barebones, minimal Dart server that distributes the incoming requests across 6 Isolates:

import 'dart:io';
import 'dart:isolate';

void main() async {
  for (var i = 1; i < 6; i++) {
    Isolate.spawn(_startServer, []);
  }

  // Bind one server in current Isolate
  _startServer();

  print('Serving at http://localhost:8080/');
  await ProcessSignal.sigterm.watch().first;
}

void _startServer([List args]) async {
  final server = await HttpServer.bind(
    InternetAddress.loopbackIPv4,
    8080,
    shared: true, // This is the magic sauce
  );

  await for (final request in server) {
    _handleRequest(request);
  }
}

void _handleRequest(HttpRequest request) async {
  // Fake delay
  await Future.delayed(const Duration(seconds: 2));

  request.response.write('Hello, world!');
  await request.response.close();
}