[flutter_tools] resolve host address in the flutter tool for web server (#48992)

packages/flutter_tools/lib/src/build_runner/resident_web_runner.dart

@@ -402,7 +402,7 @@ class _ExperimentalResidentWebRunner extends ResidentWebRunner {
       hostPort,
       packagesFilePath,
     );
-    await device.devFS.create();
+    final Uri url = await device.devFS.create();
     await _updateDevFS(fullRestart: true);
     device.generator.accept();
     await device.device.startApp(
@@ -410,7 +410,7 @@ class _ExperimentalResidentWebRunner extends ResidentWebRunner {
       mainPath: target,
       debuggingOptions: debuggingOptions,
       platformArgs: <String, Object>{
-        'uri': 'http://$effectiveHostname:$hostPort',
+        'uri': url.toString(),
       },
     );
     return attach(

packages/flutter_tools/lib/src/build_runner/web_fs.dart

@@ -333,13 +333,17 @@ class WebFs {
     Cascade cascade = Cascade();
     cascade = cascade.add(handler);
     cascade = cascade.add(assetServer.handle);
-    final HttpServer server = await httpMultiServerFactory(effectiveHostname, hostPort);
+    final InternetAddress internetAddress = (await InternetAddress.lookup(effectiveHostname)).first;
+    final HttpServer server = await httpMultiServerFactory(internetAddress, hostPort);
     shelf_io.serveRequests(server, cascade.handler);
     final WebFs webFS = WebFs(
       client,
       server,
       dwds,
-      'http://$effectiveHostname:$hostPort/',
+      // Format ipv6 hosts according to RFC 5952.
+      internetAddress.type == InternetAddressType.IPv4
+        ? '${internetAddress.address}:$hostPort'
+        : '[${internetAddress.address}]:$hostPort',
       assetServer,
       buildInfo.isDebug,
       flutterProject,

packages/flutter_tools/lib/src/web/devfs_web.dart

@@ -28,7 +28,7 @@ import 'bootstrap.dart';
 /// This is only used in development mode.
 class WebAssetServer {
   @visibleForTesting
-  WebAssetServer(this._httpServer, this._packages,
+  WebAssetServer(this._httpServer, this._packages, this.internetAddress,
       {@required void Function(dynamic, StackTrace) onError}) {
     _httpServer.listen((HttpRequest request) {
       _handleRequest(request).catchError(onError);
@@ -46,10 +46,11 @@ class WebAssetServer {
   /// trace.
   static Future<WebAssetServer> start(String hostname, int port) async {
     try {
-      final HttpServer httpServer = await HttpServer.bind(hostname, port);
+      final InternetAddress address = (await InternetAddress.lookup(hostname)).first;
+      final HttpServer httpServer = await HttpServer.bind(address, port);
       final Packages packages =
           await loadPackagesFile(Uri.base.resolve('.packages'));
-      return WebAssetServer(httpServer, packages,
+      return WebAssetServer(httpServer, packages, address,
           onError: (dynamic error, StackTrace stackTrace) {
         httpServer.close(force: true);
         throwToolExit(
@@ -71,6 +72,7 @@ class WebAssetServer {
   final RegExp _drivePath = RegExp(r'\/[A-Z]:\/');
 
   final Packages _packages;
+  final InternetAddress internetAddress;
 
   // handle requests for JavaScript source, dart sources maps, or asset files.
   Future<void> _handleRequest(HttpRequest request) async {
@@ -274,7 +276,13 @@ class WebDevFS implements DevFS {
   @override
   Future<Uri> create() async {
     _webAssetServer = await WebAssetServer.start(hostname, port);
-    return Uri.base;
+    final InternetAddress internetAddress = _webAssetServer.internetAddress;
+    // Format ipv6 hosts according to RFC 5952.
+    return Uri.parse(
+      internetAddress.type == InternetAddressType.IPv4
+        ? '${internetAddress.address}:$port'
+        : '[${internetAddress.address}]:$port'
+    );
   }
 
   @override

packages/flutter_tools/test/general.shard/web/devfs_web_test.dart

@@ -68,7 +68,7 @@ void main() {
         closeCompleter.complete();
       });
       webAssetServer = WebAssetServer(
-          mockHttpServer, packages, onError: (dynamic error, StackTrace stackTrace) {
+          mockHttpServer, packages, InternetAddress.loopbackIPv4, onError: (dynamic error, StackTrace stackTrace) {
         closeCompleter.completeError(error, stackTrace);
       });
     });

packages/flutter_tools/test/general.shard/web/web_fs_test.dart

@@ -32,11 +32,9 @@ void main() {
   MockOperatingSystemUtils mockOperatingSystemUtils;
   MockProcessUtils mockProcessUtils;
   bool lastInitializePlatform;
-  dynamic lastAddress;
   int lastPort;
 
   setUp(() {
-    lastAddress = null;
     lastPort = null;
     lastInitializePlatform = null;
     mockBuildDaemonCreator =  MockBuildDaemonCreator();
@@ -95,7 +93,6 @@ void main() {
         ChromeLauncher: () => mockChromeLauncher,
         ProcessUtils: () => mockProcessUtils,
         HttpMultiServerFactory: () => (dynamic address, int port) async {
-          lastAddress = address;
           lastPort = port;
           return mockHttpMultiServer;
         },
@@ -178,15 +175,17 @@ void main() {
       buildInfo: BuildInfo.debug,
       flutterProject: flutterProject,
       initializePlatform: false,
-      hostname: 'foo',
+      hostname: 'localhost',
       port: '1234',
       urlTunneller: null,
       dartDefines: const <String>[],
     );
 
-    expect(webFs.uri, contains('foo:1234'));
+    // Might be either ipv4 or ipv6 for localhost.
+    final bool hasExpectedUri = webFs.uri.toString().contains('[::1]:1234') ||
+                                webFs.uri.toString().contains('127.0.0.1:1234');
+    expect(hasExpectedUri, true);
     expect(lastPort, 1234);
-    expect(lastAddress, contains('foo'));
   }));
 
   test('Throws exception if build fails', () => testbed.run(() async {