close resources on application stop

src/main/java/vc/Application.java

@@ -27,6 +27,7 @@
 import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
 import org.springframework.web.client.RestTemplate;
 
+import javax.annotation.PreDestroy;
 import java.time.Duration;
 import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
@@ -38,6 +39,8 @@ public class Application {
     @Value("${BOT_TOKEN}")
     String token;
     private static final Logger LOGGER = getLogger("Application");
+    private GatewayDiscordClient gatewayDiscordClient;
+    private ScheduledExecutorService scheduledExecutorService;
 
     public static void main(String[] args) {
         new SpringApplicationBuilder(Application.class)
@@ -54,12 +57,13 @@ public ClientHttpRequestFactory clientHttpRequestFactory() {
 
     @Bean
     public GatewayDiscordClient gatewayDiscordClient() {
-        return DiscordClientBuilder.create(token).build()
+        this.gatewayDiscordClient = DiscordClientBuilder.create(token).build()
                 .gateway()
                 .setEnabledIntents(IntentSet.of(Intent.GUILDS))
                 .setInitialPresence(ignore -> ClientPresence.of(Status.ONLINE, ClientActivity.custom("/commands")))
                 .login()
                 .block();
+        return this.gatewayDiscordClient;
     }
 
     @Bean
@@ -91,12 +95,28 @@ public ObjectMapper objectMapper() {
         mapper.registerModule(new JsonNullableModule());
         return mapper;
     }
+
     @Bean
     public ScheduledExecutorService scheduledExecutorService() {
-        return Executors.newScheduledThreadPool(4, new ThreadFactoryBuilder()
+        this.scheduledExecutorService = Executors.newScheduledThreadPool(4, new ThreadFactoryBuilder()
                 .setDaemon(true)
                 .setNameFormat("scheduled-%d")
                 .setUncaughtExceptionHandler((t, e) -> LOGGER.error("Uncaught exception in scheduled thread: {}", t.getName(), e))
             .build());
+        return this.scheduledExecutorService;
+    }
+
+    @PreDestroy
+    public void onDestroy() {
+        try {
+            if (this.gatewayDiscordClient != null) {
+                this.gatewayDiscordClient.logout().block();
+            }
+            if (this.scheduledExecutorService != null) {
+                this.scheduledExecutorService.shutdownNow();
+            }
+        } catch (Exception e) {
+            LOGGER.error("Error during shutdown", e);
+        }
     }
 }

src/main/java/vc/config/GuildConfigDatabase.java

@@ -2,6 +2,7 @@
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.DisposableBean;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.stereotype.Component;
 
@@ -20,7 +21,7 @@
 import java.util.Optional;
 
 @Component
-public class GuildConfigDatabase {
+public class GuildConfigDatabase implements DisposableBean {
     private static final Logger LOGGER = LoggerFactory.getLogger(GuildConfigDatabase.class);
     // backups older than this date will be deleted
     private static final Duration ROLLING_BACKUP_DURATION = Duration.ofDays(7);
@@ -48,10 +49,10 @@ public GuildConfigDatabase(
             LOGGER.error("Error initializing guild config database connection", e);
             throw new RuntimeException(e);
         }
-        Runtime.getRuntime().addShutdownHook(new Thread(this::close));
     }
 
-    private void close() {
+    @Override
+    public void destroy() {
         try {
             connection.close();
         } catch (final Exception e) {

src/main/java/vc/config/RemoteDatabaseBackup.java

@@ -4,6 +4,7 @@
 import io.minio.messages.Item;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.DisposableBean;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.stereotype.Component;
 
@@ -13,7 +14,7 @@
 import java.util.stream.StreamSupport;
 
 @Component
-public class RemoteDatabaseBackup {
+public class RemoteDatabaseBackup implements DisposableBean {
     private static final Logger LOGGER = LoggerFactory.getLogger("RemoteDatabaseBackup");
     private final String bucketName;
     private final MinioClient minioClient;
@@ -105,4 +106,13 @@ public void downloadDatabaseBackup(final String backupPath) {
             throw new RuntimeException(e);
         }
     }
+
+    @Override
+    public void destroy() {
+        try {
+            minioClient.close();
+        } catch (final Exception e) {
+            LOGGER.error("Error closing Minio client", e);
+        }
+    }
 }

src/main/java/vc/live/RedisClient.java

@@ -4,11 +4,15 @@
 import org.redisson.api.RBoundedBlockingQueue;
 import org.redisson.api.RedissonClient;
 import org.redisson.config.Config;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.DisposableBean;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.stereotype.Component;
 
 @Component
-public class RedisClient {
+public class RedisClient implements DisposableBean {
+    private static final Logger LOGGER = LoggerFactory.getLogger(RedisClient.class);
     private RedissonClient redissonClient;
 
     public RedisClient(@Value("${REDIS_URL}") final String redisURL, @Value("${REDIS_USERNAME}") final String redisUsername, @Value("${REDIS_PASSWORD}") final String redisPassword) {
@@ -31,4 +35,13 @@ public RedissonClient buildRedisClient(final String redisURL, final String redis
             .setConnectionMinimumIdleSize(1);
         return Redisson.create(config);
     }
+
+    @Override
+    public void destroy() {
+        try {
+            redissonClient.shutdown();
+        } catch (Exception e) {
+            LOGGER.error("Failed to shutdown Redisson client", e);
+        }
+    }
 }