优化返回逻辑

src/main/java/com/knowledge/base/application/service/LLMAppServiceImpl.java

@@ -1,6 +1,7 @@
 package com.knowledge.base.application.service;
 
 import com.knowledge.base.infrastructure.south.llm.LLMServiceFactory;
+import com.knowledge.base.infrastructure.util.http.FilteredSseOutputAdapter;
 import com.knowledge.base.infrastructure.util.http.SseOutputAdapter;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
@@ -24,10 +25,11 @@ public class LLMAppServiceImpl implements LLMAppService {
     @Override
     public SseEmitter ask(String llmToken, String question, Map<String, Object> params) throws Exception {
         SseEmitter emitter = new SseEmitter(0L); // 不超时
-        SseOutputAdapter writer = new SseOutputAdapter(emitter);
 
         try {
-            llmServiceFactory.current().streamAnswer(llmToken, question, params, writer);
+            FilteredSseOutputAdapter adapter = new FilteredSseOutputAdapter(emitter);
+            llmServiceFactory.current().streamAnswer(llmToken, question, params, adapter);
+            adapter.flushLastChunk(); // 收尾发一次 sources
             emitter.complete();
         } catch (Exception e) {
             log.error("LLM调用异常", e);

src/main/java/com/knowledge/base/infrastructure/util/http/FilteredSseOutputAdapter.java

@@ -0,0 +1,66 @@
+package com.knowledge.base.infrastructure.util.http;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.web.servlet.mvc.method.annotation.SseEmitter;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+
+@Slf4j
+public class FilteredSseOutputAdapter implements WriterAdapter {
+
+    private final SseEmitter emitter;
+    private static final ObjectMapper mapper = new ObjectMapper();
+
+    private Map<String, Object> lastChunk = new HashMap<>();
+
+    public FilteredSseOutputAdapter(SseEmitter emitter) {
+        this.emitter = emitter;
+    }
+
+    @Override
+    public void writeLine(String line) throws IOException {
+        if (line == null || line.isBlank()) return;
+
+        if (line.startsWith("data:")) {
+            line = line.substring(5).trim();
+        }
+
+        try {
+            Map<String, Object> original = mapper.readValue(line, Map.class);
+            Map<String, Object> filtered = new HashMap<>();
+
+            // 累积 textResponse
+            if (original.containsKey("textResponse")) {
+                filtered.put("textResponse", original.get("textResponse"));
+                lastChunk.put("textResponse", original.get("textResponse"));
+            }
+
+            // 如果含有 sources，延迟输出，合并到最后一条 textResponse 中
+            if (original.containsKey("sources")) {
+                lastChunk.put("sources", original.get("sources"));
+                return; // 暂不发送
+            }
+
+            if (!filtered.isEmpty()) {
+                String payload = mapper.writeValueAsString(filtered);
+                emitter.send("data: " + payload + "\n\n");
+            }
+
+        } catch (Exception e) {
+            log.warn("SSE数据解析失败：{}", line, e);
+        }
+    }
+
+    public void flushLastChunk() {
+        if (lastChunk.isEmpty()) return;
+        try {
+            String finalJson = mapper.writeValueAsString(lastChunk);
+            emitter.send("data: " + finalJson + "\n\n");
+        } catch (Exception e) {
+            log.warn("flush 最后一条 SSE 失败", e);
+        }
+    }
+}

src/main/java/com/knowledge/base/infrastructure/util/http/SseOutputAdapter.java

@@ -23,7 +23,7 @@ public class SseOutputAdapter implements WriterAdapter {
         // 如果 line 以 "data: " 开头，则去除该前缀
         if (line.startsWith("data:")) {
             log.debug("[LLM-SSE] line received: {}", line);
-            line = line.substring(6).trim();
+            line = line.substring(5).trim();
         }
 
         // 发送单行 SSE 事件