Making Network http error SocketException: Failed host lookup

[hoc081098]

Steps to Reproduce

Making Network http error when build release, even having internet connection
When build debug having no error

Error: SocketException: Failed host lookup: 'jsonplaceholder.typicode' (OS  Error No address associated with hostname, error = 7)

Code:

main.dart:

import 'dart:convert';

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

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData.dark(),
      home: const MyHomePage(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({Key key}) : super(key: key);
  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  static const url = 'https://jsonplaceholder.typicode.com/users';

  Future<List<Map<String, dynamic>>> _future;

  @override
  void initState() {
    super.initState();
    _future = fetch();
  }

  Future<List<Map<String, dynamic>>> fetch() {
    return http
        .get(url)
        .then((response) {
          return response.statusCode == 200
              ? response.body
              : throw 'Error when getting data';
        })
        .then((body) => json.decode(body))
        .then((list) => (list as List).cast<Map<String, dynamic>>());
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Home'),
      ),
      body: RefreshIndicator(
        onRefresh: () async {
          _future = fetch();
          setState(() {});
          return _future;
        },
        child: FutureBuilder<List<Map<String, dynamic>>>(
          future: _future,
          builder: (context, snapshot) {
            if (snapshot.hasError) {
              return Center(
                child: Container(
                  constraints: BoxConstraints.expand(),
                  child: SingleChildScrollView(
                    physics: AlwaysScrollableScrollPhysics(),
                    child: Text(snapshot.error.toString()),
                  ),
                ),
              );
            }

            if (!snapshot.hasData) {
              return Center(
                child: CircularProgressIndicator(),
              );
            }
            return ListView.builder(
              itemCount: snapshot.data.length,
              itemBuilder: (BuildContext context, int index) {
                final item = snapshot.data[index];
                return ListTile(
                  title: Text(item['name']),
                  subtitle: Text(item['email']),
                );
              },
            );
          },
        ),
      ),
    );
  }
}

Screenshots:

Lenovo a2010: android 5.1

Philips S337: android 5.1:

Logs

flutter analyze

Analyzing test_http...
No issues found! (ran in 3.5s)

flutter doctor -v

[√] Flutter (Channel dev, v1.2.0, on Microsoft Windows [Version 10.0.17134.523], locale en-US)
    • Flutter version 1.2.0 at C:\flutter\flutter
    • Framework revision 06b979c4d5 (3 weeks ago), 2019-01-25 14:27:35 -0500
    • Engine revision 36acd02c94
    • Dart version 2.1.1 (build 2.1.1-dev.3.2 f4afaee422)

[√] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
    • Android SDK at C:\Users\Admin\AppData\Local\Android\sdk
    • Android NDK location not configured (optional; useful for native profiling support)
    • Platform android-28, build-tools 28.0.3
    • Java binary at: E:\Admin\Other\android-preview\android-studio\jre\bin\java
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1248-b01)
    • All Android licenses accepted.

[!] Android Studio (version 3.3)
    • Android Studio at E:\Admin\Other\android-preview\android-studio
    X Flutter plugin not installed; this adds Flutter specific functionality.
    X Dart plugin not installed; this adds Dart specific functionality.
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1248-b01)

[√] IntelliJ IDEA Community Edition (version 2018.3)
    • IntelliJ at C:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2018.3.3
    • Flutter plugin version 32.0.3
    • Dart plugin version 183.5153.38

[√] VS Code (version 1.31.0)
    • VS Code at C:\Users\Admin\AppData\Local\Programs\Microsoft VS Code
    • Flutter extension version 2.22.3

[√] Connected device (1 available)
    • Philips S337 • FS011641B06736 • android-arm • Android 5.1 (API 22)

[zoechi]

Are you using a proxy?

[hoc081098]

No. I don't use proxy

[zoechi]

Hard to tell. Looks like a network issue.
Do other remote or local network adresses work?

[hoc081098]

I tried many network but still not working

[zoechi]

Shouldn't this be jsonplaceholder.typicode.com instead of jsonplaceholder.typicode?

[zoechi]

Please consider asking support questions in one of the other channels listed at http://flutter.io/support .

[hoc081098]

i think that url is not a problem.
paste url https://jsonplaceholder.typicode.com/users in browser working well
static const url = 'https://jsonplaceholder.typicode.com/users'; in class _MyHomePageState

[zoechi]

@mraleph could this be a tree-shaking issue or something like that?
(sorry, don't know whom else to summon)

[hoc081098]

i rebuild release app and this is error:

E/flutter (11529): [ERROR:flutter/lib/ui/ui_dart_state.cc(148)] Unhandled Exception: HandshakeException: Handshake error in client (OS Error:
E/flutter (11529):      BAD_SIGNATURE(ecdsa.c:247)
E/flutter (11529):      BAD_SIGNATURE(handshake_client.cc:1060))
E/flutter (11529): #0      IOClient.send (package:http/src/io_client.dart:33:23)
E/flutter (11529): <asynchronous suspension>
E/flutter (11529): #1      BaseClient._sendUnstreamed (package:http/src/base_client.dart:169:38)
E/flutter (11529): <asynchronous suspension>
E/flutter (11529): #2      BaseClient.get (package:http/src/base_client.dart:32:7)
E/flutter (11529): #3      get.<anonymous closure> (package:http/http.dart:46:36)
E/flutter (11529): #4      _withClient (package:http/http.dart:166:20)
E/flutter (11529): <asynchronous suspension>
E/flutter (11529): #5      get (package:http/http.dart:46:5)
E/flutter (11529): #6      _MyHomePageState.fetch (package:test_http/main.dart:37:12)
E/flutter (11529): #7      _MyHomePageState.build.<anonymous closure> (package:test_http/main.dart:56:21)
E/flutter (11529): <asynchronous suspension>
E/flutter (11529): #8      RefreshIndicatorState._show.<anonymous closure> (package:flutter/src/material/refresh_indicator.dart:357:53)
E/flutter (11529): #9      _rootRunUnary (dart:async/zone.dart:1132:38)
E/flutter (11529): #10     _CustomZone.runUnary (dart:async/zone.dart:1029:19)
E/flutter (11529): #11     _FutureListener.handleValue (dart:async/future_impl.dart:126:18)
E/flutter (11529): #12     Future._propagateToListeners.handleValueCallback (dart:async/future_impl.dart:639:45)

E/flutter (11529): #13     Future._propagateToListeners (dart:async/future_impl.dart:668:32)
E/flutter (11529): #14     Future._completeWithValue (dart:async/future_impl.dart:483:5)
E/flutter (11529): #15     Future._asyncComplete.<anonymous closure> (dart:async/future_impl.dart:513:7)
E/flutter (11529): #16     _rootRun (dart:async/zone.dart:1124:13)
E/flutter (11529): #17     _CustomZone.run (dart:async/zone.dart:1021:19)
E/flutter (11529): #18     _CustomZone.runGuarded (dart:async/zone.dart:923:7)
E/flutter (11529): #19     _CustomZone.bindCallbackGuarded.<anonymous closure> (dart:async/zone.dart:963:23)
E/flutter (11529): #20     _microtaskLoop (dart:async/schedule_microtask.dart:41:21)
E/flutter (11529): #21     _startMicrotaskLoop (dart:async/schedule_microtask.dart:50:5)
E/flutter (11529):

[hoc081098]

same problem in stackoverflow: https://stackoverflow.com/questions/54728717/error-when-using-https-with-flutter-http-dart-package, https://stackoverflow.com/questions/54285172/how-to-solve-flutter-certificate-verify-failed-error-while-performing-a-post-req

[zarko-tg]

@hoc081098 Double-check / make sure you have
<uses-permission android:name="android.permission.INTERNET" />
in your app's android/app/src/main/AndroidManifest.xml

[hoc081098]

Thank @zarko-tg.

Solve: add <uses-permission android:name="android.permission.INTERNET" /> to android/app/src/main/AndroidManifest.xml

[ferso]

Thank @zarko-tg.

Solve: add <uses-permission android:name="android.permission.INTERNET" /> to android/app/src/main/AndroidManifest.xml

This saves me, Why this is not in the documentation ?

[zarko-tg]

@ferso It'd be less to worry about or consult documentation if they'd make it a default (in templates/starters) since most apps connect online. I spent like a day on a silly little thing.

[xai1983kbu]

I had that error even in Debug mode (android/app/src/debug/AndroidManifest.xml has
<uses-permission android:name="android.permission.INTERNET" />)

Adding internet permission is not only a solution,
You also have to make sure that you are online whether it is mobile or emulator (c)
https://stackoverflow.com/a/55548864/9783262

I wiped data
C:\Users\UN\AppData\Local\Android\Sdk\emulator> .\emulator -avd Nexus_5X_API_28 -wipe-data
(or via Android Studio)
and run main.dart

It works!
p.s. it's not related to release but I hope it will save time to someone.

[RobertB4]

Adding <uses-permission android:name="android.permission.INTERNET" /> solved this issue for me.

The documentation is out of date and should be updated. Since Flutter uses the internet permission internally in development mode it is always active when developing. When deploying the app to the play store, it is not active by default.

The documentation currently says:

uses-permission: Remove the android.permission.INTERNET permission if your application code does not need Internet access. The standard template includes this tag to enable communication between Flutter tools and a running app.

Which is misleading since the internet permission isn't in the production manifest (apparently it was in earlier flutter versions?). Please add a note to this so the documentation accurately explains that the internet permission has to be added to the production manifest in case it is needed.

[atapas]

@hoc081098 Double-check / make sure you have
<uses-permission android:name="android.permission.INTERNET" />
in your app's android/app/src/main/AndroidManifest.xml

Great Info. This helped me.

As I was wondering a bit that, where to add this line in that file... figured it out to be at the end like:

[alvinkonda]

This line used to be there on default on previous version of Flutter. It seems that they have removed on the recent updates.

[abhisawesome]

Make sure the debugging device internet is turned on , if you use localhost try changing it into 10.0.2.2

[Emyboy]

Thank @zarko-tg.

Solve: add <uses-permission android:name="android.permission.INTERNET" /> to android/app/src/main/AndroidManifest.xml

would I have to restart the app before it works? Mine isn't working.

[zarko-tg]

@Emyboy yes, it means building and starting the app again. If it isn't working that your are likely having some other problem, unrelated to this Github issue.

[Abdusin]

@hoc081098 Double-check / make sure you have
<uses-permission android:name="android.permission.INTERNET" />
in your app's android/app/src/main/AndroidManifest.xml

@zarko-tg pls help me this way dont solve my problem
flutter/flutter/#43357

[tonysader]

@hoc081098 Double-check / make sure you have
<uses-permission android:name="android.permission.INTERNET" />
in your app's android/app/src/main/AndroidManifest.xml

@zarko-tg Thanks man that saved me too!

[SuperManHa]

@hoc081098 Double-check / make sure you have
<uses-permission android:name="android.permission.INTERNET" />
in your app's android/app/src/main/AndroidManifest.xml

great! works for me!!

[bismarkstoney]

After trying all the steps. if You are running the server locally. In my case Strapi. Replace the localhost with http://localhost:1337/auth/local/register to http://10.0.2.2:1337/auth/local/register

[ph55]

I get this error on IOS.

SocketException: Failed host lookup: 'locallhost'

The solution listed here is for Android though.
Anyone managed to fix it for iPhone simulator ?

[Purvik]

@ph55 Hey, having same issue on iOS. Did you manage to solve it?

[cahyowhy]

already set permission but still got that err

environment:
  sdk: ">=2.3.0 <3.0.0"
  ....
..
flutter_svg: ^0.14.0

[xRose1]

I cant display my api pictures due to this

[ericchuawc]

i tried and can't work too..

then realised my android simulator wifi is off... need to enable it ya :)

[sumonhub]

make sure your device has internet connection.

[akadatsky]

I have this issue on release build, but debug build works ok.
Manual adding
works, but its waird why it works on debug build

[enasellithy]

@hoc081098 Double-check / make sure you have
<uses-permission android:name="android.permission.INTERNET" />
in your app's android/app/src/main/AndroidManifest.xml

please help my i have same isuee and i try your way not working with me i use this this endpoint
https://yts.mx/api/v2/list_movies.json

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. If you are still experiencing a similar issue, please open a new bug, including the output of flutter doctor -v and a minimal reproduction of the issue.