From 8032a5ca5a54be1d7bfe0f471464ded2a4375e3d Mon Sep 17 00:00:00 2001
From: Vishesh Handa <me@vhanda.in>
Date: Thu, 24 Sep 2020 20:44:56 +0200
Subject: [PATCH] Experiment with mdns to resolve a service

---
 lib/main_dns.dart | 37 +++++++++++++++++++++++++++++++++++++
 pubspec.lock      |  7 +++++++
 pubspec.yaml      |  1 +
 3 files changed, 45 insertions(+)
 create mode 100644 lib/main_dns.dart

diff --git a/lib/main_dns.dart b/lib/main_dns.dart
new file mode 100644
index 00000000..4b168bce
--- /dev/null
+++ b/lib/main_dns.dart
@@ -0,0 +1,37 @@
+import 'package:multicast_dns/multicast_dns.dart';
+
+Future<void> main() async {
+  // Parse the command line arguments.
+
+  var name = '_dartobservatory._tcp.local';
+  name = '_gitjournal._tcp';
+  final MDnsClient client = MDnsClient();
+  // Start the client with default options.
+  await client.start();
+
+  print("Client started");
+
+  //var query = ResourceRecordQuery.serverPointer(name);
+  var query = ResourceRecordQuery.serverPointer(name);
+
+  // Get the PTR recod for the service.
+  await for (var ptr in client.lookup<PtrResourceRecord>(query)) {
+    print("Got ptr $ptr");
+    // Use the domainName from the PTR record to get the SRV record,
+    // which will have the port and local hostname.
+    // Note that duplicate messages may come through, especially if any
+    // other mDNS queries are running elsewhere on the machine.
+    await for (SrvResourceRecord srv in client.lookup<SrvResourceRecord>(
+        ResourceRecordQuery.service(ptr.domainName))) {
+      // Domain name will be something like
+      // - "io.flutter.example@some-iphone.local._dartobservatory._tcp.local"
+      final String bundleId =
+          ptr.domainName; //.substring(0, ptr.domainName.indexOf('@'));
+      print('Dart observatory instance found at '
+          '${srv.target}:${srv.port} for "$bundleId".');
+    }
+  }
+  client.stop();
+
+  print('Done.');
+}
diff --git a/pubspec.lock b/pubspec.lock
index cd39b9ae..96e40626 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -574,6 +574,13 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "0.9.6+3"
+  multicast_dns:
+    dependency: "direct main"
+    description:
+      name: multicast_dns
+      url: "https://pub.dartlang.org"
+    source: hosted
+    version: "0.2.2"
   mutex:
     dependency: "direct main"
     description:
diff --git a/pubspec.yaml b/pubspec.yaml
index 16229c63..e39c7198 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -56,6 +56,7 @@ dependencies:
   in_app_purchase: ^0.3.4+5
   flutter_plugin_android_lifecycle: ^1.0.8 # for fixing the build
   timeago: ^2.0.27
+  multicast_dns: ^0.2.2
 
 dev_dependencies:
   flutter_launcher_icons: "^0.7.2"