From 4c45d71ab39e02d4e6a9aabdd12124a7d7b310e7 Mon Sep 17 00:00:00 2001
From: James Yuzawa <jtyuzawa@gmail.com>
Date: Sun, 9 Jun 2024 10:37:13 -0400
Subject: [PATCH] mdn advertise

---
 src/dist/conf/config.yml                      |  1 +
 .../googolplex_theater/ServiceDiscovery.java  | 20 +++++++++++++++++--
 .../ServiceDiscoveryTest.java                 |  9 ++++++++-
 3 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/src/dist/conf/config.yml b/src/dist/conf/config.yml
index e885d71..58e91f9 100644
--- a/src/dist/conf/config.yml
+++ b/src/dist/conf/config.yml
@@ -12,3 +12,4 @@
 #  retry-interval: 15s
 #  devices-path: conf/devices.yml
 #  preferred-interface: eth0
+#  advertise: true
diff --git a/src/main/java/com/jyuzawa/googolplex_theater/ServiceDiscovery.java b/src/main/java/com/jyuzawa/googolplex_theater/ServiceDiscovery.java
index 3d68c4c..995cf76 100644
--- a/src/main/java/com/jyuzawa/googolplex_theater/ServiceDiscovery.java
+++ b/src/main/java/com/jyuzawa/googolplex_theater/ServiceDiscovery.java
@@ -15,10 +15,13 @@
 import javax.annotation.PostConstruct;
 import javax.jmdns.JmDNS;
 import javax.jmdns.ServiceEvent;
+import javax.jmdns.ServiceInfo;
 import javax.jmdns.ServiceListener;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Value;
+import org.springframework.boot.web.context.WebServerInitializedEvent;
+import org.springframework.context.event.EventListener;
 import org.springframework.stereotype.Component;
 
 /**
@@ -30,16 +33,21 @@
 @Component
 public final class ServiceDiscovery implements Closeable {
     public static final String MDNS_SERVICE_NAME = "_googlecast._tcp.local.";
+    private static final String MDNS_ADVERTISE_NAME = "_http._tcp.local.";
+    private static final String MDNS_NAME = "googolplex-theater";
 
     private final GoogolplexService service;
     private final JmDNS mdns;
+    private final boolean advertise;
 
     @Autowired
     public ServiceDiscovery(
             GoogolplexService service,
-            @Value("${googolplex-theater.preferred-interface:#{null}}") String preferredInterface)
+            @Value("${googolplex-theater.preferred-interface:#{null}}") String preferredInterface,
+            @Value("${googolplex-theater.advertise:#{false}}") boolean advertise)
             throws IOException {
         this.service = service;
+        this.advertise = advertise;
         InetAddress inetAddress = getInterfaceAddress(preferredInterface);
         if (inetAddress == null) {
             log.warn("No IP address for service discovery found. Falling back to JmDNS library default.");
@@ -49,10 +57,18 @@ public ServiceDiscovery(
     }
 
     @PostConstruct
-    public void start() {
+    public void start() throws IOException {
         this.mdns.addServiceListener(MDNS_SERVICE_NAME, new ServiceDiscoveryListener());
     }
 
+    @EventListener
+    public void onApplicationEvent(WebServerInitializedEvent event) throws IOException {
+        if (advertise) {
+            int port = event.getWebServer().getPort();
+            this.mdns.registerService(ServiceInfo.create(MDNS_ADVERTISE_NAME, MDNS_NAME, port, MDNS_NAME));
+        }
+    }
+
     static InetAddress getInterfaceAddress(String preferredInterface) throws SocketException, UnknownHostException {
         if (preferredInterface != null) {
             return getBestInetAddress(getPreferredInterface(preferredInterface));
diff --git a/src/test/java/com/jyuzawa/googolplex_theater/ServiceDiscoveryTest.java b/src/test/java/com/jyuzawa/googolplex_theater/ServiceDiscoveryTest.java
index c6606b3..cab9fc6 100644
--- a/src/test/java/com/jyuzawa/googolplex_theater/ServiceDiscoveryTest.java
+++ b/src/test/java/com/jyuzawa/googolplex_theater/ServiceDiscoveryTest.java
@@ -12,6 +12,8 @@
 import java.net.NetworkInterface;
 import org.junit.jupiter.api.Test;
 import org.mockito.Mockito;
+import org.springframework.boot.web.context.WebServerInitializedEvent;
+import org.springframework.boot.web.server.WebServer;
 
 class ServiceDiscoveryTest {
 
@@ -30,7 +32,12 @@ void preferredInterfaceTest() throws Exception {
     @Test
     void instantiationTest() throws IOException {
         GoogolplexService controller = Mockito.mock(GoogolplexService.class);
-        ServiceDiscovery sd = new ServiceDiscovery(controller, null);
+        ServiceDiscovery sd = new ServiceDiscovery(controller, null, true);
+        WebServerInitializedEvent event = Mockito.mock(WebServerInitializedEvent.class);
+        WebServer webServer = Mockito.mock(WebServer.class);
+        Mockito.when(event.getWebServer()).thenReturn(webServer);
+        Mockito.when(webServer.getPort()).thenReturn(8080);
+        sd.onApplicationEvent(event);
         sd.close();
     }
 }