feat(example): Improve the example code

examples_dart/bin/omemo_client.dart

@@ -1,18 +1,12 @@
 import 'package:args/args.dart';
 import 'package:chalkdart/chalk.dart';
 import 'package:cli_repl/cli_repl.dart';
+import 'package:example_dart/socket.dart';
 import 'package:logging/logging.dart';
 import 'package:moxxmpp/moxxmpp.dart';
 import 'package:moxxmpp_socket_tcp/moxxmpp_socket_tcp.dart';
 import 'package:omemo_dart/omemo_dart.dart' as omemo;
 
-class TestingTCPSocketWrapper extends TCPSocketWrapper {
-  @override
-  bool onBadCertificate(dynamic certificate, String domain) {
-    return true;
-  }
-}
-
 void main(List<String> args) async {
   // Set up logging
   Logger.root.level = Level.ALL;
@@ -28,9 +22,23 @@ void main(List<String> args) async {
     ..addOption('password')
     ..addOption('host')
     ..addOption('port')
-    ..addOption('to');
+    ..addOption('to')
+    ..addOption('xmpps-srv');
   final options = parser.parse(args);
 
+  // Parse a potential xmpps-client SRV record here.
+  // Format: --xmpps-srv <priority>,<weight>,<target>,<port>
+  MoxSrvRecord? srvRecord;
+  if (options['xmpps-srv'] != null) {
+    final parts = (options['xmpps-srv']! as String).split(',');
+    srvRecord = MoxSrvRecord(
+      int.parse(parts[0]),
+      int.parse(parts[1]),
+      parts[2],
+      int.parse(parts[3]),
+    );
+  }
+
   // Connect
   final jid = JID.fromString(options['jid']! as String);
   final to = JID.fromString(options['to']! as String).toBare();
@@ -39,7 +47,7 @@ void main(List<String> args) async {
     TestingReconnectionPolicy(),
     AlwaysConnectedConnectivityManager(),
     ClientToServerNegotiator(),
-    TestingTCPSocketWrapper(),
+    ExampleTCPSocketWrapper(srvRecord),
   )..connectionSettings = ConnectionSettings(
       jid: jid,
       password: options['password']! as String,
@@ -89,13 +97,14 @@ void main(List<String> args) async {
       final body = event.encryptionError != null
           ? chalk.red('Failed to decrypt message: ${event.encryptionError}')
           : chalk.green(event.get<MessageBodyData>()?.body ?? '');
-      print('[${event.from.toString()}] ' + body);
+      print('[${event.from.toString()}] $body');
     }
   });
 
   // Connect
   Logger.root.info('Connecting...');
-  final result = await connection.connect(shouldReconnect: false, waitUntilLogin: true);
+  final result =
+      await connection.connect(shouldReconnect: false, waitUntilLogin: true);
   if (!result.isType<bool>()) {
     Logger.root.severe('Authentication failed!');
     return;
@@ -107,13 +116,16 @@ void main(List<String> args) async {
   final device = await oom.getDevice();
   final omemoResult = await moxxmppOmemo.publishBundle(await device.toBundle());
   if (!omemoResult.isType<bool>()) {
-    Logger.root.severe('Failed to publish OMEMO bundle: ${omemoResult.get<OmemoError>()}');
+    Logger.root.severe(
+        'Failed to publish OMEMO bundle: ${omemoResult.get<OmemoError>()}');
     return;
   }
 
   final repl = Repl(prompt: '> ');
   await for (final line in repl.runAsync()) {
-    await connection.getManagerById<MessageManager>(messageManager)!.sendMessage(
+    await connection
+        .getManagerById<MessageManager>(messageManager)!
+        .sendMessage(
           to,
           TypedMap<StanzaHandlerExtension>.fromList([
             MessageBodyData(line),

examples_dart/lib/socket.dart

@@ -0,0 +1,22 @@
+import 'package:moxxmpp_socket_tcp/moxxmpp_socket_tcp.dart';
+
+/// A simple socket for examples that allows injection of SRV records (since
+/// we cannot use moxdns here).
+class ExampleTCPSocketWrapper extends TCPSocketWrapper {
+  ExampleTCPSocketWrapper(this.srvRecord);
+
+  /// A potential SRV record to inject for testing.
+  final MoxSrvRecord? srvRecord;
+
+  @override
+  bool onBadCertificate(dynamic certificate, String domain) {
+    return true;
+  }
+
+  @override
+  Future<List<MoxSrvRecord>> srvQuery(String domain, bool dnssec) async {
+    return [
+      if (srvRecord != null) srvRecord!,
+    ];
+  }
+}