test/http_client_stays_alive_test.dart

// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

// OtherResources=http_client_stays_alive_test.dart

import 'dart:async';
import 'dart:io' hide HttpServer, HttpRequest, HttpClient;

import "package:http_io/http_io.dart";
import "package:test/test.dart";

// NOTE: This test tries to ensure that an HttpClient will close it's
// underlying idle connections after [HttpClient.idleTimeout].
//
// The main script spawns a server and a subprocess which does a connection back
// to it.
// The subprocess is expected to shut down its idle sockets after
// [HttpClient.idleTimeout] and the main script will assert that this happens
// within +/- 2 <= seconds.

const SECONDS = 4;

List<String> packageOptions() {
  if (Platform.packageConfig != null) {
    return <String>['--packages=${Platform.packageConfig}'];
  } else {
    return <String>[];
  }
}

Future<Null> runServerProcess() {
  Completer<Null> completer = new Completer();
  HttpServer.bind('127.0.0.1', 0).then((server) {
    var url = 'http://127.0.0.1:${server.port}/';

    server.idleTimeout = const Duration(hours: 1);

    var subscription = server.listen((HttpRequest request) {
      request.response
        ..write('hello world')
        ..close();
    });

    var sw = new Stopwatch()..start();
    var script =
        "${Directory.current.path}/test/http_client_stays_alive_test.dart";
    if (!(new File(script)).existsSync()) {
      // If we can't find the file relative to the cwd, then look relative to
      // Platform.script.
      script = Platform.script
          .resolve('http_client_stays_alive_test.dart')
          .toFilePath();
    }

    var arguments = packageOptions()..add(script);
    Process.run(Platform.executable, arguments, environment: {'URL': url})
        .then((res) {
      subscription.cancel();
      if (res.exitCode != 0) {
        throw "Child exited with ${res.exitCode} instead of 0. "
            "(stdout: ${res.stdout}, stderr: ${res.stderr})";
      }
      var seconds = sw.elapsed.inSeconds;
      // NOTE: There is a slight chance this will cause flakiness, but there is
      // no other good way of testing correctness of timing-dependent code
      // form the outside.
      if (seconds < SECONDS || (SECONDS + 30) < seconds) {
        throw "Child did exit within $seconds seconds, but expected it to take "
            "roughly $SECONDS seconds.";
      }

      completer.complete(null);
    });
  });
  return completer.future;
}

runClientProcess(String url) {
  var uri = Uri.parse(url);

  // NOTE: We make an HTTP client request and then *forget to close* the HTTP
  // client instance. The idle timer should fire after SECONDS.
  var client = new HttpClient();
  client.idleTimeout = const Duration(seconds: SECONDS);

  client
      .getUrl(uri)
      .then((req) => req.close())
      .then((response) => response.drain())
      .then((_) => print('drained client request'));
}

main() {
  if (Platform.environment['URL'] != null) {
    runClientProcess(Platform.environment['URL']);
  } else {
    test("ClientStaysAlive", runServerProcess);
  }
}