Erweiterungen

src/main/java/de/assecutor/votianlt/messaging/delivery/MessageDeliveryServiceImpl.java

@@ -7,14 +7,24 @@ import de.assecutor.votianlt.messaging.plugin.SendOptions;
 import de.assecutor.votianlt.repository.MessageEnvelopeRepository;
 import de.assecutor.votianlt.repository.PendingDeliveryRepository;
 import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Value;
 import org.springframework.stereotype.Service;
 
+import jakarta.annotation.PostConstruct;
+import jakarta.annotation.PreDestroy;
+
 import java.nio.charset.StandardCharsets;
 import java.time.Duration;
 import java.time.LocalDateTime;
+import java.util.ArrayList;
 import java.util.List;
+import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
 
 /**
  * Implementation of MessageDeliveryService with reliable delivery guarantees.
@@ -23,6 +33,12 @@ import java.util.concurrent.CompletableFuture;
 @Slf4j
 public class MessageDeliveryServiceImpl implements MessageDeliveryService {
 
+    @Value("${app.messaging.delivery.ack-retry-interval-seconds:5}")
+    private int ackRetryIntervalSeconds;
+
+    @Value("${app.messaging.delivery.ack-max-retries:4}")
+    private int ackMaxRetries;
+
     private final PluginManager pluginManager;
     private final PendingDeliveryRepository pendingDeliveryRepository;
     private final MessageEnvelopeRepository envelopeRepository;
@@ -30,6 +46,31 @@ public class MessageDeliveryServiceImpl implements MessageDeliveryService {
     private final DeliveryConfig config;
     private final ObjectMapper objectMapper;
 
+    // In-memory tracking of messages awaiting acknowledgment
+    private final Map<String, PendingAckMessage> pendingAckMessages = new ConcurrentHashMap<>();
+    private ScheduledExecutorService retryScheduler;
+
+    /**
+     * Holds information about a message pending acknowledgment.
+     */
+    private static class PendingAckMessage {
+        final String messageId;
+        final String clientId;
+        final String messageType;
+        final byte[] envelopeData;
+        final String json;
+        int retryCount;
+
+        PendingAckMessage(String messageId, String clientId, String messageType, byte[] envelopeData, String json) {
+            this.messageId = messageId;
+            this.clientId = clientId;
+            this.messageType = messageType;
+            this.envelopeData = envelopeData;
+            this.json = json;
+            this.retryCount = 0;
+        }
+    }
+
     public MessageDeliveryServiceImpl(
             PluginManager pluginManager,
             PendingDeliveryRepository pendingDeliveryRepository,
@@ -45,6 +86,86 @@ public class MessageDeliveryServiceImpl implements MessageDeliveryService {
         this.objectMapper = objectMapper;
     }
 
+    @PostConstruct
+    public void startRetryScheduler() {
+        retryScheduler = Executors.newSingleThreadScheduledExecutor(r -> {
+            Thread t = new Thread(r, "message-retry-scheduler");
+            t.setDaemon(true);
+            return t;
+        });
+        retryScheduler.scheduleAtFixedRate(
+                this::checkAndRetryPendingAckMessages,
+                ackRetryIntervalSeconds,
+                ackRetryIntervalSeconds,
+                TimeUnit.SECONDS
+        );
+        log.info("[MessageDelivery] Started retry scheduler (interval: {}s, max retries: {})",
+                ackRetryIntervalSeconds, ackMaxRetries);
+    }
+
+    @PreDestroy
+    public void stopRetryScheduler() {
+        if (retryScheduler != null) {
+            retryScheduler.shutdown();
+            try {
+                if (!retryScheduler.awaitTermination(5, TimeUnit.SECONDS)) {
+                    retryScheduler.shutdownNow();
+                }
+            } catch (InterruptedException e) {
+                retryScheduler.shutdownNow();
+                Thread.currentThread().interrupt();
+            }
+            log.info("[MessageDelivery] Stopped retry scheduler");
+        }
+    }
+
+    /**
+     * Check for pending messages and retry sending them.
+     * Called every RETRY_INTERVAL_SECONDS seconds.
+     */
+    private void checkAndRetryPendingAckMessages() {
+        if (pendingAckMessages.isEmpty()) {
+            return;
+        }
+
+        log.debug("[MessageDelivery] Checking {} pending messages for retry", pendingAckMessages.size());
+
+        List<String> toRemove = new ArrayList<>();
+
+        for (PendingAckMessage pending : pendingAckMessages.values()) {
+            pending.retryCount++;
+
+            if (pending.retryCount > ackMaxRetries) {
+                // Max retries reached - log and remove
+                log.error("[MessageDelivery] Message {} not acknowledged after {} attempts. Removing from retry queue. JSON: {}",
+                        pending.messageId, ackMaxRetries, pending.json);
+                toRemove.add(pending.messageId);
+            } else {
+                // Retry sending
+                log.info("[MessageDelivery] Retrying message {} (attempt {}/{})",
+                        pending.messageId, pending.retryCount, ackMaxRetries);
+
+                try {
+                    SendOptions sendOptions = SendOptions.reliable();
+                    pluginManager.sendToClient(pending.clientId, pending.messageType, pending.envelopeData, sendOptions)
+                            .thenAccept(v -> log.info("[MessageDelivery] Retry {} sent successfully for message {}",
+                                    pending.retryCount, pending.messageId))
+                            .exceptionally(ex -> {
+                                log.error("[MessageDelivery] Retry {} failed for message {}: {}",
+                                        pending.retryCount, pending.messageId, ex.getMessage());
+                                return null;
+                            });
+                } catch (Exception e) {
+                    log.error("[MessageDelivery] Error during retry for message {}: {}",
+                            pending.messageId, e.getMessage(), e);
+                }
+            }
+        }
+
+        // Remove messages that exceeded max retries
+        toRemove.forEach(pendingAckMessages::remove);
+    }
+
     @Override
     public CompletableFuture<DeliveryReceipt> sendToClient(String clientId, String messageType, Object payload, DeliveryOptions options) {
         try {
@@ -76,6 +197,11 @@ public class MessageDeliveryServiceImpl implements MessageDeliveryService {
                 );
                 pendingDeliveryRepository.save(pending);
                 log.debug("[MessageDelivery] Created pending delivery for message {}", messageId);
+
+                // Add to in-memory retry queue
+                PendingAckMessage pendingAck = new PendingAckMessage(messageId, clientId, messageType, envelopeData, json);
+                pendingAckMessages.put(messageId, pendingAck);
+                log.info("[MessageDelivery] Added message {} to retry queue (requires ACK)", messageId);
             }
 
             // Send via plugin manager
@@ -156,6 +282,12 @@ public class MessageDeliveryServiceImpl implements MessageDeliveryService {
             log.info("[MessageDelivery] Received acknowledgment for message {} with status {}",
                     ack.getMessageId(), ack.getStatus());
 
+            // Remove from in-memory retry queue
+            PendingAckMessage removed = pendingAckMessages.remove(ack.getMessageId());
+            if (removed != null) {
+                log.info("[MessageDelivery] Removed message {} from retry queue (ACK received)", ack.getMessageId());
+            }
+
             Optional<PendingDelivery> pendingOpt = pendingDeliveryRepository.findByMessageId(ack.getMessageId());
 
             if (pendingOpt.isEmpty()) {

src/main/resources/application.properties

@@ -67,6 +67,8 @@ app.messaging.delivery.message-expiry=24h
 app.messaging.delivery.cleanup-interval-minutes=60
 app.messaging.delivery.retry-interval-seconds=30
 app.messaging.delivery.acknowledged-retention-days=7
+app.messaging.delivery.ack-retry-interval-seconds=5
+app.messaging.delivery.ack-max-retries=4
 
 # Messaging Plugin Configuration
 app.messaging.plugin.type=mqtt