WIP

[demos/kafka/chat] / src / main / java / de / juplo / kafka / chat / backend / implementation / StorageStrategy.java

diff --git a/src/main/java/de/juplo/kafka/chat/backend/implementation/StorageStrategy.java b/src/main/java/de/juplo/kafka/chat/backend/implementation/StorageStrategy.java
index cbf55a4..98db975 100644 (file)
--- a/src/main/java/de/juplo/kafka/chat/backend/implementation/StorageStrategy.java
+++ b/src/main/java/de/juplo/kafka/chat/backend/implementation/StorageStrategy.java
@@ -1,30 +1,95 @@
-package de.juplo.kafka.chat.backend.persistence;
+package de.juplo.kafka.chat.backend.implementation;
 
 import de.juplo.kafka.chat.backend.domain.ChatHomeService;
 import de.juplo.kafka.chat.backend.domain.ChatRoomInfo;
 import de.juplo.kafka.chat.backend.domain.Message;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import reactor.core.publisher.Flux;
 
 import java.util.UUID;
+import java.util.concurrent.Phaser;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.function.BiConsumer;
+import java.util.function.Consumer;
 
 
 public interface StorageStrategy
 {
+  Logger log = LoggerFactory.getLogger(StorageStrategy.class.getCanonicalName());
+
+  AtomicBoolean running = new AtomicBoolean(true);
+
+
   default void write(ChatHomeService chatHomeService)
   {
+    if (!running.getAndSet(false))
+    {
+      log.info("{} is not running, skip write...", chatHomeService);
+      return;
+    }
+
+    Phaser writtenChatRooms = new Phaser(1);
+    AtomicInteger numErrors = new AtomicInteger();
+
     writeChatRoomInfo(
         chatHomeService
             .getChatRoomInfo()
-            .doOnNext(chatRoomInfo ->
-                writeChatRoomData(
-                    chatRoomInfo.getId(),
-                    chatHomeService
-                        .getChatRoomData(chatRoomInfo.getId())
-                        .flatMapMany(chatRoomData -> chatRoomData.getMessages()))));
+            .doOnNext(chatRoomInfo -> writtenChatRooms.register())
+            .doOnNext(chatRoomInfo -> writeChatRoomData(
+                chatRoomInfo.getId(),
+                chatHomeService
+                    .getChatRoomData(chatRoomInfo.getId())
+                    .flatMapMany(chatRoomData -> chatRoomData.getMessages()),
+                (chatRoomId) ->
+                {
+                  logSuccess(chatRoomId);
+                  writtenChatRooms.arriveAndDeregister();
+                },
+                (chatRoomId, throwable) ->
+                {
+                  logFailure(chatRoomId, throwable);
+                  numErrors.incrementAndGet();
+                  writtenChatRooms.arriveAndDeregister();
+                })));
+
+    writtenChatRooms.arriveAndAwaitAdvance();
+    if (numErrors.get() > 0)
+    {
+      throw new RuntimeException("Could not write all chat-rooms for " + chatHomeService);
+    }
+
+    log.info("All chat-rooms were written successfully for {}", chatHomeService);
   }
 
   void writeChatRoomInfo(Flux<ChatRoomInfo> chatRoomInfoFlux);
   Flux<ChatRoomInfo> readChatRoomInfo();
+  default void writeChatRoomData(
+      UUID chatRoomId,
+      Flux<Message> messageFlux,
+      SuccessCallback successCallback,
+      FailureCallback failureCallback)
+  {
+    writeChatRoomData(
+        chatRoomId,
+        messageFlux
+            .doOnComplete(() -> successCallback.accept(chatRoomId))
+            .doOnError(throwable -> failureCallback.accept(chatRoomId, throwable)));
+  }
   void writeChatRoomData(UUID chatRoomId, Flux<Message> messageFlux);
   Flux<Message> readChatRoomData(UUID chatRoomId);
+
+  interface SuccessCallback extends Consumer<UUID> {}
+  interface FailureCallback extends BiConsumer<UUID, Throwable> {}
+
+  default void logSuccess(UUID chatRoomId)
+  {
+    log.info("Successfully stored chat-room {}", chatRoomId);
+  }
+
+  default void logFailure(UUID chatRoomId, Throwable throwable)
+  {
+    log.error("Could not store chat-room {}: {}", chatRoomId, throwable);
+  }
 }