fix(rag): restore single-round source streaming

frontend-web/src/components/workspace/chats/chat-box.tsx

@@ -780,11 +780,10 @@ function buildTurnReferenceBatches(
       continue;
     }
     const nextHumanIndex = findNextHumanIndex(messages, index + 1);
-    if (nextHumanIndex === -1 && isLoading) {
-      continue;
-    }
     const endIndex = nextHumanIndex === -1 ? messages.length : nextHumanIndex;
-    const assistant = findLastAssistantAnswer(messages, index + 1, endIndex);
+    const assistant =
+      findLastAssistantAnswer(messages, index + 1, endIndex) ??
+      findFrontendRagAssistant(messages, index + 1, endIndex);
     if (!assistant?.id) {
       continue;
     }
@@ -794,6 +793,13 @@ function buildTurnReferenceBatches(
         nextHumanIndex === -1 ? undefined : messages[nextHumanIndex]?.id,
       includeBeforeMessage: false,
     }).filter((source) => source.mode !== "none");
+    // Single-round RAG sends sources before the complete answer. Expose those
+    // sources immediately while preserving the normal streaming-turn behavior.
+    const isFrontendRagTurn =
+      isSingleRoundRagMessage(assistant) || isMultiRoundRagMessage(assistant);
+    if (nextHumanIndex === -1 && isLoading && !isFrontendRagTurn) {
+      continue;
+    }
     if (sources.length > 0) {
       batches.push({
         id: assistant.id,
@@ -832,6 +838,23 @@ function findLastAssistantAnswer(
   return null;
 }
 
+function findFrontendRagAssistant(
+  messages: Message[],
+  start: number,
+  end: number,
+): Message | null {
+  for (let index = end - 1; index >= start; index -= 1) {
+    const message = messages[index];
+    if (
+      message?.type === "ai" &&
+      (isSingleRoundRagMessage(message) || isMultiRoundRagMessage(message))
+    ) {
+      return message;
+    }
+  }
+  return null;
+}
+
 function hasAssistantAnswerContent(message: Message): boolean {
   const content = message.content;
   if (typeof content === "string") {

frontend-web/src/core/threads/use-single-round-rag.ts

@@ -5,7 +5,7 @@ import { readRuntimeEnv } from "@/env";
 
 const STORAGE_PREFIX = "workspace.single-round-rag.";
 
-type KnowledgeBaseChunk = {
+type KnowledgeBaseChunk = Record<string, unknown> & {
   answer?: unknown;
   docs?: unknown;
 };
@@ -168,36 +168,112 @@ function parseKnowledgeBaseChunk(jsonText: string): KnowledgeBaseChunk {
   }
 }
 
-function flattenDocs(value: unknown): Record<string, unknown>[] {
-  if (Array.isArray(value)) {
-    return value.flatMap((item) => flattenDocs(item));
+function readString(...values: unknown[]): string | undefined {
+  for (const value of values) {
+    if (typeof value === "string" && value.trim()) return value;
   }
-  if (!value || typeof value !== "object") return [];
-  const record = value as Record<string, unknown>;
-  if ("docs" in record) return flattenDocs(record.docs);
-  return [record];
+  return undefined;
 }
 
-function normalizeSources(value: unknown): RagSource[] {
-  return flattenDocs(value).map((item, index) => {
-    const title = String(item.m_title ?? item.title ?? item.source ?? `参考资料 ${index + 1}`);
-    const content = String(item.m_content ?? item.content ?? item.snippet ?? "");
-    const source = item.source1 ?? item.source;
-    const rawUrl = item.url ?? item.link ?? item.href;
-    return {
-      id: String(item.recUuid ?? item.rec_uuid ?? item.uuid ?? item.id ?? "") || undefined,
-      title,
-      type: String(item.source1 ?? item.type ?? "知识库"),
-      snippet: content,
-      content,
-      source: typeof source === "string" ? source : undefined,
-      time: typeof item.m_publish === "string" ? item.m_publish : undefined,
-      url: typeof rawUrl === "string" && /^https?:\/\//i.test(rawUrl) ? rawUrl : undefined,
-      raw: item,
-    };
+function docsFallbackContent(docs: unknown): string | undefined {
+  const candidates = Array.isArray(docs) ? docs : [docs];
+  return readString(...candidates);
+}
+
+function buildKnowledgeDetailUrl(recUuid: string | undefined): string | undefined {
+  const knowledgeUrl = readRuntimeEnv("VITE_AIPI_KNOWLEDGE_URL")?.replace(/\/$/, "");
+  if (!knowledgeUrl || !recUuid) return undefined;
+  return `${knowledgeUrl}/#/knowledge/mid-detail?recUuid=${encodeURIComponent(recUuid)}`;
+}
+
+function toRagSource(
+  record: Record<string, unknown>,
+  index: number,
+  fallbackContent?: string,
+): RagSource {
+  const title =
+    readString(record.m_title, record.title, record.source, record.source1) ??
+    `参考资料 ${index + 1}`;
+  const content =
+    readString(
+      record.m_content,
+      // Some deployed responses spell this field incorrectly; keep it as a
+      // read-only compatibility alias rather than dropping the document.
+      record.m_conent,
+      record.content,
+      record.snippet,
+      fallbackContent,
+      record.url,
+  ) ?? "";
+  const source = readString(record.source1, record.source, record.m_source);
+  const rawUrl = readString(record.url, record.link, record.href);
+  const recUuid = readString(record.recUuid, record.rec_uuid, record.uuid, record.id);
+  return {
+    id: recUuid,
+    title,
+    type: readString(record.type, record.source1) ?? "知识库",
+    snippet: content,
+    content,
+    source,
+    time: readString(record.m_publish, record.m_publicsh, record.time),
+    url:
+      buildKnowledgeDetailUrl(recUuid) ??
+      (rawUrl && /^https?:\/\//i.test(rawUrl) ? rawUrl : undefined),
+    raw: record,
+  };
+}
+
+/**
+ * A single-RAG stream is a concatenation of source envelopes, for example:
+ * `{docs:["..."], recUuid:"...", m_title:"...", m_content:"..."}`.
+ * The root-level metadata is the source; `docs` merely marks the envelope and
+ * supplies a fallback body. This mirrors GeneralQA's per-chunk processing.
+ */
+function normalizeSources(chunk: KnowledgeBaseChunk): RagSource[] {
+  const hasRootMetadata = [
+    chunk.recUuid,
+    chunk.rec_uuid,
+    chunk.m_title,
+    chunk.m_content,
+    chunk.m_conent,
+    chunk.source1,
+    chunk.m_publish,
+    chunk.m_publicsh,
+  ].some((value) => typeof value === "string" && value.trim());
+  if (hasRootMetadata) {
+    return [toRagSource(chunk, 0, docsFallbackContent(chunk.docs))];
+  }
+
+  const docs = Array.isArray(chunk.docs) ? chunk.docs : chunk.docs ? [chunk.docs] : [];
+  return docs.flatMap((item, index): RagSource[] => {
+    if (typeof item === "string") {
+      return [toRagSource({}, index, item)];
+    }
+    if (!item || typeof item !== "object") return [];
+    return [toRagSource(item as Record<string, unknown>, index)];
   });
 }
 
+function mergeSources(current: RagSource[], incoming: RagSource[]): RagSource[] {
+  const result = [...current];
+  const keys = new Set(
+    current.map((source) =>
+      source.id
+        ? `id:${source.id}`
+        : `content:${source.title}\u0000${source.content}\u0000${source.source ?? ""}`,
+    ),
+  );
+  for (const source of incoming) {
+    const key = source.id
+      ? `id:${source.id}`
+      : `content:${source.title}\u0000${source.content}\u0000${source.source ?? ""}`;
+    if (keys.has(key)) continue;
+    keys.add(key);
+    result.push(source);
+  }
+  return result;
+}
+
 function createId(prefix: string) {
   return `${prefix}-${crypto.randomUUID()}`;
 }
@@ -397,7 +473,9 @@ export function useSingleRoundRagMessages(threadId: string) {
           for (const jsonText of extracted.objects) {
             const chunk = parseKnowledgeBaseChunk(jsonText);
             if (typeof chunk.answer === "string") answerChunks.push({ answer: chunk.answer });
-            if (chunk.docs !== undefined) sources = normalizeSources(chunk.docs);
+            if (chunk.docs !== undefined) {
+              sources = mergeSources(sources, normalizeSources(chunk));
+            }
             refreshAssistant();
           }
         }