feat: 添加Dify平台集成支持

- 升级 dify-sdk-java 从 1.0.7 到 1.2.6
- 新增 ChatModeType.DIFY 枚举类型
- 新增 DifyChatServiceImpl、DifyConversationService、DifyWorkflowService 实现
- 新增 DifyStreamingChatModel 流式聊天模型
- 支持Dify工作流对话模式
- Dify自带RAG知识库时跳过本地向量库查询

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

pom.xml

@@ -58,7 +58,7 @@
         <langchain4j.community.version>1.13.0-beta23</langchain4j.community.version>
         <langgraph4j.version>1.5.3</langgraph4j.version>
         <weaviate.version>1.19.6</weaviate.version>
-        <dify.version>1.0.7</dify.version>
+        <dify.version>1.2.6</dify.version>
         <!-- gRPC 版本 - 解决 Milvus SDK 依赖冲突 -->
         <grpc.version>1.62.2</grpc.version>
         <!-- Apache Commons Compress - 用于POI处理ZIP格式 -->

ruoyi-modules/ruoyi-chat/src/main/java/org/ruoyi/enums/ChatModeType.java

@@ -18,7 +18,8 @@ public enum ChatModeType {
     PPIO("ppio", "ppio"),
     CUSTOM_API("custom_api", "自定义API"),
     MINIMAX("minimax", "MiniMax"),
-    XIAOMI("xiaomi", "小米MiMo");
+    XIAOMI("xiaomi", "小米MiMo"),
+    DIFY("dify", "Dify平台");
     private final String code;
     private final String description;
 

ruoyi-modules/ruoyi-chat/src/main/java/org/ruoyi/service/chat/impl/ChatServiceFacade.java

@@ -47,6 +47,7 @@ import org.ruoyi.common.sse.core.SseEmitterManager;
 import org.ruoyi.common.sse.utils.SseMessageUtils;
 import org.ruoyi.domain.bo.vector.QueryVectorBo;
 import org.ruoyi.domain.vo.knowledge.KnowledgeInfoVo;
+import org.ruoyi.enums.ChatModeType;
 import org.ruoyi.factory.ChatServiceFactory;
 import org.ruoyi.mcp.service.core.ToolProviderFactory;
 import org.ruoyi.observability.*;
@@ -97,6 +98,8 @@ public class ChatServiceFacade implements IChatService {
 
     private final ToolProviderFactory toolProviderFactory;
 
+    private final org.ruoyi.service.chat.impl.provider.DifyWorkflowService difyWorkflowService;
+
     /**
      * 内存实例缓存，避免同一会话重复创建
      * Key: sessionId, Value: MessageWindowChatMemory实例
@@ -163,6 +166,14 @@ public class ChatServiceFacade implements IChatService {
      * @return 如果需要提前返回则返回SseEmitter，否则返回null
      */
     private SseEmitter handleSpecialChatModes(ChatRequest chatRequest) {
+        // 处理 Dify 工作流对话
+        if (chatRequest.getEnableWorkFlow()
+                && chatRequest.getChatModelVo() != null
+                && ChatModeType.DIFY.getCode().equals(chatRequest.getChatModelVo().getProviderCode())) {
+            log.info("处理Dify工作流对话,会话: {}", chatRequest.getSessionId());
+            return difyWorkflowService.streaming(chatRequest.getChatModelVo(), chatRequest);
+        }
+
         // 处理工作流对话
         if (chatRequest.getEnableWorkFlow()) {
             log.info("处理工作流对话,会话: {}", chatRequest.getSessionId());
@@ -430,8 +441,12 @@ public class ChatServiceFacade implements IChatService {
             }
         }
 
+        // Dify 自带 RAG 知识库检索，跳过本地向量库查询
+        boolean isDifyProvider = chatRequest.getChatModelVo() != null
+                && ChatModeType.DIFY.getCode().equals(chatRequest.getChatModelVo().getProviderCode());
+
         // 从向量库查询相关历史消息（知识库内容作为上下文）
-        if (chatRequest.getKnowledgeId() != null) {
+        if (chatRequest.getKnowledgeId() != null && !isDifyProvider) {
             // 查询知识库信息
             KnowledgeInfoVo knowledgeInfoVo = knowledgeInfoService.queryById(Long.valueOf(chatRequest.getKnowledgeId()));
             if (knowledgeInfoVo == null) {

ruoyi-modules/ruoyi-chat/src/main/java/org/ruoyi/service/chat/impl/provider/DifyChatServiceImpl.java

@@ -0,0 +1,43 @@
+package org.ruoyi.service.chat.impl.provider;
+
+import dev.langchain4j.model.chat.ChatModel;
+import dev.langchain4j.model.chat.StreamingChatModel;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.ruoyi.common.chat.domain.dto.request.ChatRequest;
+import org.ruoyi.common.chat.domain.vo.chat.ChatModelVo;
+import org.ruoyi.enums.ChatModeType;
+import org.ruoyi.service.chat.AbstractChatService;
+import org.ruoyi.service.chat.impl.provider.model.DifyStreamingChatModel;
+import org.springframework.stereotype.Service;
+
+/**
+ * Dify 平台对话服务
+ * <p>
+ * 通过 dify-java-client 接入 Dify 的对话型应用 (Chat App) 和
+ * 工作流编排对话应用 (Chatflow App)，支持流式 SSE 响应。
+ *
+ * @author better
+ */
+@Service
+@Slf4j
+@RequiredArgsConstructor
+public class DifyChatServiceImpl implements AbstractChatService {
+
+    private final DifyConversationService difyConversationService;
+
+    @Override
+    public StreamingChatModel buildStreamingChatModel(ChatModelVo chatModelVo, ChatRequest chatRequest) {
+        return new DifyStreamingChatModel(chatModelVo, chatRequest, difyConversationService);
+    }
+
+    @Override
+    public ChatModel buildChatModel(ChatModelVo chatModelVo) {
+        throw new UnsupportedOperationException("Dify 不支持同步 ChatModel，请使用流式模式");
+    }
+
+    @Override
+    public String getProviderName() {
+        return ChatModeType.DIFY.getCode();
+    }
+}

ruoyi-modules/ruoyi-chat/src/main/java/org/ruoyi/service/chat/impl/provider/DifyConversationService.java

@@ -0,0 +1,35 @@
+package org.ruoyi.service.chat.impl.provider;
+
+import org.springframework.stereotype.Service;
+
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * Dify 会话映射管理
+ * <p>
+ * 维护 ruoyi sessionId 与 Dify conversation_id 的映射关系，
+ * 确保多轮对话上下文连续。
+ *
+ * @author better
+ */
+@Service
+public class DifyConversationService {
+
+    private final ConcurrentHashMap<Long, String> conversationMap = new ConcurrentHashMap<>();
+
+    public String getConversationId(Long sessionId) {
+        return conversationMap.get(sessionId);
+    }
+
+    public void saveMapping(Long sessionId, String difyConversationId) {
+        if (sessionId != null && difyConversationId != null) {
+            conversationMap.put(sessionId, difyConversationId);
+        }
+    }
+
+    public void clearMapping(Long sessionId) {
+        if (sessionId != null) {
+            conversationMap.remove(sessionId);
+        }
+    }
+}

ruoyi-modules/ruoyi-chat/src/main/java/org/ruoyi/service/chat/impl/provider/DifyWorkflowService.java

@@ -0,0 +1,137 @@
+package org.ruoyi.service.chat.impl.provider;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import io.github.imfangs.dify.client.DifyClientFactory;
+import io.github.imfangs.dify.client.DifyWorkflowClient;
+import io.github.imfangs.dify.client.enums.ResponseMode;
+import io.github.imfangs.dify.client.event.ErrorEvent;
+import io.github.imfangs.dify.client.event.WorkflowFinishedEvent;
+import io.github.imfangs.dify.client.event.WorkflowTextChunkEvent;
+import io.github.imfangs.dify.client.callback.WorkflowStreamCallback;
+import io.github.imfangs.dify.client.model.workflow.WorkflowRunRequest;
+import lombok.extern.slf4j.Slf4j;
+import org.ruoyi.common.chat.domain.dto.request.ChatRequest;
+import org.ruoyi.common.chat.domain.dto.request.WorkFlowRunner;
+import org.ruoyi.common.chat.domain.vo.chat.ChatModelVo;
+import org.ruoyi.common.sse.utils.SseMessageUtils;
+import org.springframework.stereotype.Service;
+import org.springframework.web.servlet.mvc.method.annotation.SseEmitter;
+
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.CompletableFuture;
+
+/**
+ * Dify 工作流执行服务
+ * <p>
+ * 通过 DifyWorkflowClient 调用 Dify 平台上部署的工作流应用，
+ * 并将节点事件通过 SSE 实时推送给前端。
+ *
+ * @author better
+ */
+@Service
+@Slf4j
+public class DifyWorkflowService {
+
+    /**
+     * 流式执行 Dify 工作流
+     *
+     * @param chatModelVo 模型配置（apiHost= Dify 地址, apiKey= Dify 密钥）
+     * @param chatRequest 聊天请求
+     * @return SSE emitter
+     */
+    public SseEmitter streaming(ChatModelVo chatModelVo, ChatRequest chatRequest) {
+        Long userId = chatRequest.getUserId();
+        String tokenValue = chatRequest.getTokenValue();
+        SseEmitter emitter = chatRequest.getEmitter();
+
+        // 构建 Dify 工作流请求参数
+        Map<String, Object> inputs = convertInputs(chatRequest.getWorkFlowRunner());
+
+        WorkflowRunRequest request = WorkflowRunRequest.builder()
+                .inputs(inputs)
+                .responseMode(ResponseMode.STREAMING)
+                .user(String.valueOf(userId))
+                .build();
+
+        DifyWorkflowClient client = DifyClientFactory.createWorkflowClient(
+                normalizeBaseUrl(chatModelVo.getApiHost()),
+                chatModelVo.getApiKey());
+
+        // 异步执行，避免阻塞请求线程
+        CompletableFuture.runAsync(() -> {
+            try {
+                client.runWorkflowStream(request, new WorkflowStreamCallback() {
+
+                    @Override
+                    public void onWorkflowTextChunk(WorkflowTextChunkEvent event) {
+                        String text = event.getData() != null ? event.getData().getText() : null;
+                        if (text != null) {
+                            SseMessageUtils.sendContent(userId, text);
+                        }
+                    }
+
+                    @Override
+                    public void onWorkflowFinished(WorkflowFinishedEvent event) {
+                        // 将最终输出作为内容发送
+                        if (event.getData() != null && event.getData().getOutputs() != null) {
+                            Map<String, Object> outputs = event.getData().getOutputs();
+                            for (Map.Entry<String, Object> entry : outputs.entrySet()) {
+                                SseMessageUtils.sendContent(userId,
+                                        entry.getKey() + ": " + entry.getValue() + "\n");
+                            }
+                        }
+                        SseMessageUtils.sendDone(userId);
+                        SseMessageUtils.completeConnection(userId, tokenValue);
+                    }
+
+                    @Override
+                    public void onError(ErrorEvent event) {
+                        SseMessageUtils.sendError(userId, event.getMessage());
+                    }
+
+                    @Override
+                    public void onException(Throwable throwable) {
+                        log.error("Dify 工作流执行异常", throwable);
+                        SseMessageUtils.sendError(userId, throwable.getMessage());
+                        SseMessageUtils.completeConnection(userId, tokenValue);
+                    }
+                });
+            } catch (Exception e) {
+                log.error("Dify 工作流执行失败", e);
+                SseMessageUtils.sendError(userId, e.getMessage());
+                SseMessageUtils.completeConnection(userId, tokenValue);
+            }
+        });
+
+        return emitter;
+    }
+
+    /**
+     * 将 WorkFlowRunner.inputs (List<ObjectNode>) 转换为 Dify 所需的 Map
+     */
+    private Map<String, Object> convertInputs(WorkFlowRunner runner) {
+        Map<String, Object> result = new HashMap<>();
+        if (runner == null || runner.getInputs() == null) {
+            return result;
+        }
+        for (ObjectNode node : runner.getInputs()) {
+            Iterator<Map.Entry<String, JsonNode>> fields = node.fields();
+            while (fields.hasNext()) {
+                Map.Entry<String, JsonNode> field = fields.next();
+                result.put(field.getKey(), field.getValue().asText());
+            }
+        }
+        return result;
+    }
+
+    private String normalizeBaseUrl(String baseUrl) {
+        if (baseUrl == null || baseUrl.isBlank()) {
+            throw new IllegalArgumentException("Dify API 地址(apiHost)不能为空");
+        }
+        return baseUrl.endsWith("/") ? baseUrl.substring(0, baseUrl.length() - 1) : baseUrl;
+    }
+}

ruoyi-modules/ruoyi-chat/src/main/java/org/ruoyi/service/chat/impl/provider/model/DifyStreamingChatModel.java

@@ -0,0 +1,172 @@
+package org.ruoyi.service.chat.impl.provider.model;
+
+import dev.langchain4j.data.message.AiMessage;
+import dev.langchain4j.data.message.ChatMessage;
+import dev.langchain4j.data.message.UserMessage;
+import dev.langchain4j.model.chat.StreamingChatModel;
+import dev.langchain4j.model.chat.response.ChatResponse;
+import dev.langchain4j.model.chat.response.StreamingChatResponseHandler;
+import io.github.imfangs.dify.client.DifyChatClient;
+import io.github.imfangs.dify.client.DifyClientFactory;
+import io.github.imfangs.dify.client.enums.ResponseMode;
+import io.github.imfangs.dify.client.event.ErrorEvent;
+import io.github.imfangs.dify.client.event.MessageEndEvent;
+import io.github.imfangs.dify.client.event.MessageEvent;
+import lombok.extern.slf4j.Slf4j;
+import org.ruoyi.common.chat.domain.dto.request.ChatRequest;
+import org.ruoyi.common.chat.domain.vo.chat.ChatModelVo;
+import org.ruoyi.service.chat.impl.provider.DifyConversationService;
+
+import java.util.List;
+
+/**
+ * Dify 流式聊天模型适配器
+ * <p>
+ * 将 Dify 的回调式流式响应适配为 langchain4j 的 StreamingChatModel 接口，
+ * 使 ChatServiceFacade 可以像其他 provider 一样统一调用。
+ *
+ * @author better
+ */
+@Slf4j
+public class DifyStreamingChatModel implements StreamingChatModel {
+
+    private final ChatModelVo chatModelVo;
+    private final ChatRequest chatRequest;
+    private final DifyConversationService conversationService;
+
+    public DifyStreamingChatModel(ChatModelVo chatModelVo, ChatRequest chatRequest,
+                                  DifyConversationService conversationService) {
+        this.chatModelVo = chatModelVo;
+        this.chatRequest = chatRequest;
+        this.conversationService = conversationService;
+    }
+
+    @Override
+    public void chat(List<ChatMessage> messages, StreamingChatResponseHandler handler) {
+        // 1. 从 langchain4j 消息列表中提取最后一条用户消息作为 query
+        String query = extractUserQuery(messages);
+
+        // 2. 获取 Dify conversation_id（多轮对话连续性）
+        String conversationId = null;
+        if (chatRequest.getSessionId() != null) {
+            conversationId = conversationService.getConversationId(chatRequest.getSessionId());
+        }
+
+        // 3. 构建 Dify 请求
+        io.github.imfangs.dify.client.model.chat.ChatMessage difyMessage = io.github.imfangs.dify.client.model.chat.ChatMessage.builder()
+                .query(query)
+                .user(String.valueOf(chatRequest.getUserId()))
+                .responseMode(ResponseMode.STREAMING)
+                .conversationId(conversationId)
+                .autoGenerateName(true)
+                .build();
+
+        // 4. 创建 Dify 客户端并发送流式请求
+        try {
+            DifyChatClient client = DifyClientFactory.createChatClient(
+                    normalizeBaseUrl(chatModelVo.getApiHost()),
+                    chatModelVo.getApiKey());
+
+            client.sendChatMessageStream(difyMessage, new DifyChatStreamAdapter(handler));
+        } catch (Exception e) {
+            log.error("Dify 流式对话调用失败", e);
+            handler.onError(e);
+        }
+    }
+
+    @Override
+    public void chat(String userMessage, StreamingChatResponseHandler handler) {
+        io.github.imfangs.dify.client.model.chat.ChatMessage difyMessage = io.github.imfangs.dify.client.model.chat.ChatMessage.builder()
+                .query(userMessage)
+                .user(String.valueOf(chatRequest.getUserId()))
+                .responseMode(ResponseMode.STREAMING)
+                .conversationId(chatRequest.getSessionId() != null
+                        ? conversationService.getConversationId(chatRequest.getSessionId()) : null)
+                .autoGenerateName(true)
+                .build();
+
+        try {
+            DifyChatClient client = DifyClientFactory.createChatClient(
+                    normalizeBaseUrl(chatModelVo.getApiHost()),
+                    chatModelVo.getApiKey());
+
+            client.sendChatMessageStream(difyMessage, new DifyChatStreamAdapter(handler));
+        } catch (Exception e) {
+            log.error("Dify 流式对话调用失败", e);
+            handler.onError(e);
+        }
+    }
+
+    /**
+     * 从 langchain4j 消息列表中提取最后一条用户消息文本
+     */
+    private String extractUserQuery(List<ChatMessage> messages) {
+        for (int i = messages.size() - 1; i >= 0; i--) {
+            ChatMessage msg = messages.get(i);
+            if (msg instanceof UserMessage) {
+                return ((UserMessage) msg).singleText();
+            }
+        }
+        return "";
+    }
+
+    private String normalizeBaseUrl(String baseUrl) {
+        if (baseUrl == null || baseUrl.isBlank()) {
+            throw new IllegalArgumentException("Dify API 地址(apiHost)不能为空");
+        }
+        return baseUrl.endsWith("/") ? baseUrl.substring(0, baseUrl.length() - 1) : baseUrl;
+    }
+
+    /**
+     * Dify 回调适配器
+     * 将 Dify ChatStreamCallback 事件转发给 langchain4j StreamingChatResponseHandler
+     */
+    private class DifyChatStreamAdapter implements io.github.imfangs.dify.client.callback.ChatStreamCallback {
+
+        private final StreamingChatResponseHandler handler;
+        private final StringBuilder fullResponse = new StringBuilder();
+
+        DifyChatStreamAdapter(StreamingChatResponseHandler handler) {
+            this.handler = handler;
+        }
+
+        @Override
+        public void onMessage(MessageEvent event) {
+            String answer = event.getAnswer();
+            if (answer != null) {
+                fullResponse.append(answer);
+                handler.onPartialResponse(answer);
+            }
+            // 保存 Dify conversation_id 以维持多轮对话
+            if (event.getConversationId() != null && chatRequest.getSessionId() != null) {
+                conversationService.saveMapping(chatRequest.getSessionId(), event.getConversationId());
+            }
+        }
+
+        @Override
+        public void onMessageEnd(MessageEndEvent event) {
+            // 保存 conversation_id
+            if (event.getConversationId() != null && chatRequest.getSessionId() != null) {
+                conversationService.saveMapping(chatRequest.getSessionId(), event.getConversationId());
+            }
+
+            // 构建完整的 ChatResponse 交给上层处理
+            AiMessage aiMessage = new AiMessage(fullResponse.toString());
+            ChatResponse response = ChatResponse.builder()
+                    .aiMessage(aiMessage)
+                    .id(event.getMessageId())
+                    .build();
+            handler.onCompleteResponse(response);
+        }
+
+        @Override
+        public void onError(ErrorEvent event) {
+            handler.onError(new RuntimeException(event.getMessage()));
+        }
+
+        @Override
+        public void onException(Throwable throwable) {
+            handler.onError(throwable);
+        }
+    }
+}