Merge pull request #89 from weekenthralling/dev

Implement summary assistant feature

Author: weekenthralling

src/main/java/dev/chatbot/aiservice/AssistantConfiguration.java

@@ -8,8 +8,10 @@
 
 import dev.langchain4j.memory.chat.ChatMemoryProvider;
 import dev.langchain4j.memory.chat.MessageWindowChatMemory;
+import dev.langchain4j.model.chat.ChatModel;
 import dev.langchain4j.model.chat.StreamingChatModel;
 import dev.langchain4j.model.chat.listener.ChatModelListener;
+import dev.langchain4j.model.openai.OpenAiChatModel;
 import dev.langchain4j.model.openai.OpenAiStreamingChatModel;
 import dev.langchain4j.service.AiServices;
 import dev.langchain4j.web.search.WebSearchEngine;
@@ -61,6 +63,20 @@ StreamingChatModel model() {
                 .build();
     }
 
+    @Bean
+    ChatModel chatModel(StreamingChatModel streamingChatModel) {
+        return OpenAiChatModel.builder()
+                .baseUrl(llmProperties.getBaseUrl())
+                .apiKey(llmProperties.getApiKey())
+                .modelName(llmProperties.getModelName())
+                .temperature(llmProperties.getTemperature())
+                .topP(llmProperties.getTopP())
+                .maxTokens(llmProperties.getMaxTokens())
+                .returnThinking(true)
+                .listeners(listeners)
+                .build();
+    }
+
     @Bean
     @Scope(SCOPE_PROTOTYPE)
     ChatMemoryProvider chatMemoryProvider() {
@@ -86,4 +102,10 @@ StreamingAssistant assistant(
                 .chatMemoryProvider(chatMemoryProvider)
                 .build();
     }
+
+    @Bean
+    @Scope(SCOPE_PROTOTYPE)
+    SummaryAssistant summaryAssistant(ChatModel chatModel, ChatMemoryProvider chatMemoryProvider) {
+        return AiServices.builder(SummaryAssistant.class).chatModel(chatModel).build();
+    }
 }

src/main/java/dev/chatbot/aiservice/SummaryAssistant.java

@@ -0,0 +1,10 @@
+package dev.chatbot.aiservice;
+
+import dev.langchain4j.service.SystemMessage;
+import dev.langchain4j.service.UserMessage;
+
+public interface SummaryAssistant {
+
+    @SystemMessage(fromResource = "prompts/summarize_assistant_prompt.txt")
+    String summarize(@UserMessage String conversation);
+}

src/main/java/dev/chatbot/controller/AssistantController.java

@@ -1,7 +1,10 @@
 package dev.chatbot.controller;
 
 import java.time.Instant;
+import java.util.Arrays;
+import java.util.Objects;
 import java.util.UUID;
+import java.util.stream.Collectors;
 
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.PostMapping;
@@ -19,11 +22,14 @@
 import reactor.core.publisher.Flux;
 
 import dev.chatbot.aiservice.StreamingAssistant;
+import dev.chatbot.aiservice.SummaryAssistant;
 import dev.chatbot.domain.Conversation;
 import dev.chatbot.dto.ChatMessage;
 import dev.chatbot.exception.ForbiddenException;
+import dev.chatbot.repository.ChatHistoryRepository;
 import dev.chatbot.service.ConversationService;
 
+import static dev.langchain4j.data.message.ChatMessageDeserializer.messagesFromJson;
 import static org.springframework.http.MediaType.TEXT_EVENT_STREAM_VALUE;
 
 import static dev.chatbot.utils.Json.toJson;
@@ -44,8 +50,12 @@ public class AssistantController {
 
     private final StreamingAssistant assistant;
 
+    private final SummaryAssistant summaryAssistant;
+
     private final ConversationService conversationService;
 
+    private final ChatHistoryRepository chatHistoryRepository;
+
     @PostMapping(value = "/{conversationId}/assistant", produces = TEXT_EVENT_STREAM_VALUE)
     @Operation(summary = "Assistant API", description = "Get assistant response")
     @ApiResponses(
@@ -100,6 +110,25 @@ public Flux<String> assistant(
                         sink.next(toJson(thinkMessage));
                     })
                     .onCompleteResponse(response -> {
+                        // After the main response is sent, trigger summarization if enabled
+                        var requireSummarization = message.getAdditionalKwargs().get("require_summarization");
+                        if (Boolean.TRUE.equals(requireSummarization)) {
+                            String title = this.summaryAssistant.summarize(chatMessages(sessionId));
+
+                            conversation.setTitle(title);
+                            this.conversationService.saveConversation(conversation);
+
+                            // Send the updated conversation with the new title
+                            ChatMessage summaryMessage = ChatMessage.builder()
+                                    .id(UUID.randomUUID().toString())
+                                    .type("info")
+                                    .from("ai")
+                                    .sentAt(Instant.now())
+                                    .content(title)
+                                    .build();
+                            sink.next(toJson(summaryMessage));
+                        }
+
                         sink.next("[DONE]");
                         sink.complete();
                     })
@@ -117,4 +146,30 @@ public Flux<String> assistant(
                     .start();
         });
     }
+
+    /**
+     * Retrieve chat messages for a given session ID and format them as a single
+     * string.
+     * @param sessionId the session ID
+     * @return the formatted chat messages
+     */
+    private String chatMessages(UUID sessionId) {
+        var chatHistory = this.chatHistoryRepository.findById(sessionId).orElse(null);
+        if (chatHistory == null) {
+            return "No conversation history.";
+        }
+        return messagesFromJson(chatHistory.getMessage()).stream()
+                .map(ChatMessage::fromLC)
+                .filter(Objects::nonNull)
+                .filter(message -> Objects.nonNull(message.getContent()))
+                .filter(message -> Arrays.asList("human", "ai").contains(message.getType()))
+                .map(message -> {
+                    return switch (message.getType()) {
+                        case "human" -> "Human: " + message.getContent();
+                        case "ai" -> "AI: " + message.getContent();
+                        default -> "";
+                    };
+                })
+                .collect(Collectors.joining("\n"));
+    }
 }

src/main/java/dev/chatbot/controller/ConversationController.java

@@ -170,7 +170,9 @@ public ResponseEntity<Chat> getConversation(
             messages = messagesFromJson(history.getMessage()).stream()
                     .map(ChatMessage::fromLC)
                     .filter(Objects::nonNull)
-                    .filter(message -> Objects.nonNull(message.getContent()))
+                    // Remove empty messages and messages with only new lines(functional messages)
+                    .filter(message -> Objects.nonNull(message.getContent())
+                            && !message.getContent().equals("\n\n"))
                     // TODO: chatbot only stream "human" and "ai" message now, so we just show these two types
                     // here. In the future, we may need to show other types of messages.
                     .filter(message -> Arrays.asList("human", "ai").contains(message.getType()))

src/main/resources/prompts/summarize_assistant_prompt.txt

@@ -0,0 +1,10 @@
+Based on the conversation provided, generate a concise and accurate title that captures the core topic or main intent of the dialogue.
+
+Requirements:
+1. The title must be clear, professional, and highly relevant to the main subject of the conversation.
+2. The title length must be strictly limited to **20** characters (including spaces and letters).
+3. Do not introduce any information not present in the conversation.
+4. Maintain a neutral and objective tone—no exaggeration or emotional wording.
+5. Use the same language to user.
+
+Output the final title only. Do not include explanations or numbering.

web/src/routes/conversation/index.tsx

@@ -119,6 +119,9 @@ const Chatbox = () => {
         case "ToolMessageChunk": // langchain's ToolMessageChunk.type
           appendOrAddMessage(currentConvId, message);
           break;
+        case "info":
+          updateConv({ id: currentConvId, title: message.content });
+          break;
         case "error":
           showErrorNotification("发生错误", message.content);
           handleStreamComplete(currentConvId);