How to make a http request in a flutter widget test?

Question

I'm trying to make an HTTP request from within a flutter widget test, but for some reason, the widget test always times out after 5 sec, whereas it works perfectly fine in a unit test.

import 'package:flutter_test/flutter_test.dart';
import 'dart:io';
import 'dart:convert';

void main() {
  test('http unit-test works', () async {
    var httpClient = new HttpClient();
    var request = await httpClient.getUrl(Uri.parse('https://api.ipify.org/'));
    var response = await request.close();
    var responseBody = await response.transform(UTF8.decoder).join();
    print('BODY: $responseBody');
  });

  testWidgets('http widget-test does not work', (WidgetTester tester) async {
    var httpClient = new HttpClient();
    var request = await httpClient.getUrl(Uri.parse('https://api.ipify.org/'));
    var response = await request.close();
    var responseBody = await response.transform(UTF8.decoder).join();
    print('BODY: $responseBody');
  });
}

Is the flutter test environment eating my HTTP request here? How can I prevent it from doing this?

Why would you want to make HTTP requests in a test? Wouldn't you want to mock that instead? — QuirijnGB, Jan 19 '18 at 03:51
Sure. But the problem is that my app/test times-out while trying to reach the local mock-http-server. — Slyon, Jan 23 '18 at 08:09
See https://stackoverflow.com/questions/49166234/flutter-widget-tests-with-networkimage — TWL, Jan 30 '20 at 00:30
@QuirijnGB What if I have separate live and mock environments in my server, and I want to use the mock environment during flutter tests? — Amarghosh, Sep 28 '21 at 10:56

score 0 · Answer 1 · answered Feb 23 '21 at 03:01

If the cause of the issue is timeouts as you've mentioned, I suggest trying a different network during tests. WidgetTester shouldn't cause issues on HTTP Requests in Flutter Unit Tests. I tried the repro provided, but it worked fine on my tests.

For reference, here's the version of Flutter I'm running on: Flutter version 1.26.0-2.0.pre.281

How to make a http request in a flutter widget test?

1 Answers1