refactor(chat): 重构Dify聊天服务实现

- 将think标签常量改为大写命名规范
- 为blockingChat和streamChat方法添加完整的JavaDoc注释
- 移除冗余的注释代码
- 重命名内部解析方法提高可读性
- 优化流式聊天中的异常处理逻辑
- 为SSEUtil构造函数添加异常捕获机制
- 统一使用StringUtils.EMPTY替代空字符串
- 改进代码结构和错误处理流程

src/main/java/cn/com/poc/common/service/impl/DifyChatServiceImpl.java

@@ -45,15 +45,21 @@ public class DifyChatServiceImpl implements DifyChatService {
 
     private final Logger logger = LoggerFactory.getLogger(DifyChatServiceImpl.class);
 
-    private final String thinkStartTag = "<think>";
+    private final String THINK_START_TAG = "<think>";
 
-    private final String thinkEndTag = "</think>";
+    private final String THINK_END_TAG = "</think>";
 
     @Autowired
     private DifyConfigProperties difyConfigProperties;
 
     /**
      * 阻塞式聊天请求
+     *
+     * @param fileUrls 文件地址
+     * @param question 问题
+     * @param data     拓展参数
+     * @param user     用户
+     * @param apiKey   API密钥
      */
     public AgentResultEntity blockingChat(List<String> fileUrls,
                                           String question,
@@ -61,7 +67,6 @@ public class DifyChatServiceImpl implements DifyChatService {
                                           String user,
                                           String apiKey) {
 
-        // 从配置中获取API密钥，如果传入的apiKey为null或空，则从配置中查找
         String actualApiKey = apiKey;
         if (StringUtils.isEmpty(actualApiKey)) {
             actualApiKey = difyConfigProperties.getApiKeys().get(user);
@@ -100,16 +105,16 @@ public class DifyChatServiceImpl implements DifyChatService {
             AgentResultEntity agentResultEntity = new AgentResultEntity();
             String answer = chatMessageResponse.getAnswer();
 
-            int startIndex = answer.indexOf(thinkStartTag);
-            int endIndex = answer.indexOf(thinkEndTag);
+            int startIndex = answer.indexOf(THINK_START_TAG);
+            int endIndex = answer.indexOf(THINK_END_TAG);
 
             if (startIndex != -1 && endIndex != -1 && endIndex > startIndex) {
                 // 提取<think>标签内的内容
-                String reasoningContent = answer.substring(startIndex + thinkStartTag.length(), endIndex);
+                String reasoningContent = answer.substring(startIndex + THINK_START_TAG.length(), endIndex);
                 agentResultEntity.setReasoningContent(reasoningContent.trim());
 
                 // 提取其余内容（去除<think>标签部分）
-                String message = answer.substring(0, startIndex) + answer.substring(endIndex + thinkEndTag.length());
+                String message = answer.substring(0, startIndex) + answer.substring(endIndex + THINK_END_TAG.length());
                 agentResultEntity.setMessage(message);
             } else {
                 // 如果没有找到<think>标签，将整个answer作为message
@@ -126,12 +131,18 @@ public class DifyChatServiceImpl implements DifyChatService {
 
     /**
      * 流式聊天请求
+     *
+     * @param fileUrls 文件地址
+     * @param question 问题
+     * @param data     拓展参数
+     * @param user     用户
+     * @param apiKey   API密钥
      */
     public AgentResultEntity streamChat(List<String> fileUrls,
                                         String question,
                                         Map<String, Object> data,
                                         String user,
-                                        String apiKey) throws IOException, DifyApiException, InterruptedException {
+                                        String apiKey) {
         AgentResultEntity agentResultEntity = new AgentResultEntity();
 
         StringBuilder messageBuilder = new StringBuilder();
@@ -170,34 +181,40 @@ public class DifyChatServiceImpl implements DifyChatService {
         ServletRequestAttributes servletRequestAttributes =
                 (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
         HttpServletResponse response = servletRequestAttributes.getResponse();
-        // 发送消息并获取响应
-        chatClient.sendChatMessageStream(message, new ChatStreamCallback() {
-            SSEUtil sseUtil = new SSEUtil(response);
 
+        // 发送消息并获取响应
+        try {
+            chatClient.sendChatMessageStream(message, new ChatStreamCallback() {
+                SSEUtil sseUtil = new SSEUtil(response);
 
-            boolean isThink = false;
+                boolean isThink = false;
 
-            private String think(String content) {
-                if (!isThink) {
-                    if (content.contains(thinkStartTag)) {
-                        isThink = true;
-                        return content.replaceFirst(thinkStartTag, "");
-                    }
-                    return content;
-                } else {
-                    if (content.contains(thinkEndTag)) {
-                        isThink = false;
-                        return content.replaceFirst(thinkEndTag, "");
+                /**
+                 * 解析深度思考文本内容
+                 * 处理思考标记的开始和结束标签，提取纯文本内容
+                 *
+                 * @param content 原始内容
+                 * @return 解析后的文本内容，如果内容不完整则返回空字符串
+                 */
+                String parseDeepThinkingContent(String content) {
+                    if (!isThink) {
+                        if (content.contains(THINK_START_TAG)) {
+                            isThink = true;
+                            return content.replaceFirst(THINK_START_TAG, StringUtils.EMPTY);
+                        }
+                        return content;
+                    } else {
+                        if (content.contains(THINK_END_TAG)) {
+                            isThink = false;
+                            return content.replaceFirst(THINK_END_TAG, StringUtils.EMPTY);
+                        }
+                        return StringUtils.EMPTY;
                     }
-                    return null;
                 }
-            }
 
-            @Override
-            public void onMessage(MessageEvent event) {
-                try {
+                void responseMess(MessageEvent event) throws IOException {
                     if (StringUtils.isNotEmpty(event.getAnswer())) {
-                        String think = think(event.getAnswer());
+                        String think = parseDeepThinkingContent(event.getAnswer());
                         LargeModelDemandResult largeModelDemandResult = new LargeModelDemandResult();
                         if (isThink || StringUtils.isNotBlank(think)) {
                             largeModelDemandResult.setReasoningContent(think);
@@ -212,30 +229,44 @@ public class DifyChatServiceImpl implements DifyChatService {
                         largeModelDemandResult.setCode("0");
                         sseUtil.send(JsonUtils.serialize(largeModelDemandResult));
                     }
-                } catch (Exception e) {
-                    logger.error("发送SSE消息时出错: {}", e.getMessage(), e);
-                    sseUtil.completeByError(e.getMessage());
-                    throw new RuntimeException(e);
                 }
-            }
 
-            @Override
-            public void onMessageEnd(MessageEndEvent event) {
-                try {
-                    sseUtil.send("[DONE]");
-                } catch (IOException e) {
-                    logger.error("发送SSE结束消息时出错: {}", e.getMessage(), e);
-                    sseUtil.completeByError(e.getMessage());
-                    throw new RuntimeException(e);
-                } finally {
-                    sseUtil.complete();
-                    agentResultEntity.setMessage(messageBuilder.toString());
-                    agentResultEntity.setReasoningContent(reasoningContentBuilder.toString());
+                @Override
+                public void onMessage(MessageEvent event) {
+                    try {
+                        responseMess(event);
+                    } catch (Exception e) {
+                        logger.error("发送SSE消息时出错: {}", e.getMessage(), e);
+                        sseUtil.completeByError(e.getMessage());
+                        throw new RuntimeException(e);
+                    }
                 }
-                countDownLatch.countDown();
-            }
-        });
-        countDownLatch.await(120, TimeUnit.SECONDS);
-        return agentResultEntity;
+
+                @Override
+                public void onMessageEnd(MessageEndEvent event) {
+                    try {
+                        sseUtil.send("[DONE]");
+                    } catch (IOException e) {
+                        logger.error("发送SSE结束消息时出错: {}", e.getMessage(), e);
+                        sseUtil.completeByError(e.getMessage());
+                        throw new RuntimeException(e);
+                    } finally {
+                        sseUtil.complete();
+                        agentResultEntity.setMessage(messageBuilder.toString());
+                        agentResultEntity.setReasoningContent(reasoningContentBuilder.toString());
+                    }
+                    countDownLatch.countDown();
+                }
+
+            });
+            countDownLatch.await(120, TimeUnit.SECONDS);
+            return agentResultEntity;
+        } catch (Exception e) {
+            countDownLatch.notify();
+            SSEUtil sseUtil = new SSEUtil(response);
+            sseUtil.completeByError(e.getMessage());
+            throw new BusinessException(e.getMessage());
+        }
     }
+
 }
\ No newline at end of file

src/main/java/cn/com/poc/common/utils/SSEUtil.java

@@ -35,9 +35,13 @@ public class SSEUtil implements AutoCloseable {
         outputStream = response.getOutputStream();
     }
 
-    public SSEUtil(HttpServletResponse response) throws IOException {
-        response.setContentType("text/event-stream;charset=UTF-8");
-        outputStream = response.getOutputStream();
+    public SSEUtil(HttpServletResponse response) {
+        try {
+            response.setContentType("text/event-stream;charset=UTF-8");
+            outputStream = response.getOutputStream();
+        } catch (IOException e) {
+            throw new RuntimeException("无法获取HttpServletResponse");
+        }
     }
 
     public void send(String data) throws IOException {