feat: 添加图床归档任务支持，优化归档逻辑和错误处理

server/utils/openai.ts

@@ -5,6 +5,8 @@ import type { BaseOptions, IImageGenerateData } from "#shared/types/openai";
 /** 图像生成改走 Chat Completions 流式接口，通常能更快拿到中转平台返回的图片地址 */
 const CHAT_COMPLETIONS_URL = "https://api.qflink.xyz/v1/chat/completions";
 const IMAGE_GENERATION_MODEL = "gpt-image-2";
+const DEFAULT_MAX_SSE_DATA_LINE_BYTES = 1024 * 1024;
+const textEncoder = new TextEncoder();
 
 /** Chat Completions SSE 每个 data chunk 的最小结构 */
 interface IChatCompletionStreamChunk {
@@ -28,15 +30,9 @@ interface IChatCompletionStreamChunk {
 interface IImageStreamUpstreamResponse {
   content: string;
   imageUrl?: string;
-  chunks: Array<{
-    id?: string;
-    created?: number;
-    model?: string;
-    content?: string;
-    finishReason?: string | null;
-    metadata?: unknown;
-    hasUsage: boolean;
-  }>;
+  contentLength: number;
+  chunkCount: number;
+  finishReason?: string | null;
   usage?: unknown;
 }
 
@@ -221,11 +217,14 @@ const readChatCompletionStream = async (
 ): Promise<IImageStreamUpstreamResponse> => {
   const reader = stream.getReader();
   const decoder = new TextDecoder();
-  // TODO: 这里会把完整 SSE 文本和 chunk 元数据都累计到当前 Node 进程内存里，
-  // 高并发或超长响应下可能带来明显的事件循环抖动；后续可改为限制缓存窗口或只保留摘要。
-  const chunks: IImageStreamUpstreamResponse["chunks"] = [];
+  const maxDataLineBytes = getPositiveIntegerEnv(
+    "IMAGE_STREAM_MAX_SSE_LINE_BYTES",
+    DEFAULT_MAX_SSE_DATA_LINE_BYTES
+  );
   let buffer = "";
   let content = "";
+  let chunkCount = 0;
+  let finishReason: string | null | undefined;
   let usage: unknown;
 
   while (true) {
@@ -233,12 +232,14 @@ const readChatCompletionStream = async (
     if (done) break;
 
     buffer += decoder.decode(value, { stream: true });
+    assertSseBufferSize(buffer, maxDataLineBytes);
     const lines = buffer.split(/\r?\n/);
     buffer = lines.pop() ?? "";
 
     for (const line of lines) {
-      const chunk = parseSseDataLine(line);
+      const chunk = parseSseDataLine(line, maxDataLineBytes);
       if (!chunk) continue;
+      chunkCount += 1;
 
       const deltaContent = collectDeltaContent(chunk);
       if (deltaContent) {
@@ -249,23 +250,17 @@ const readChatCompletionStream = async (
         usage = chunk.usage;
       }
 
-      chunks.push({
-        id: chunk.id,
-        created: chunk.created,
-        model: chunk.model,
-        content: deltaContent || undefined,
-        finishReason: chunk.choices?.find((choice) => choice.finish_reason)
-          ?.finish_reason,
-        metadata: chunk.metadata,
-        hasUsage: Boolean(chunk.usage)
-      });
+      finishReason =
+        chunk.choices?.find((choice) => choice.finish_reason)
+          ?.finish_reason ?? finishReason;
     }
   }
 
   const finalText = buffer + decoder.decode();
   for (const line of finalText.split(/\r?\n/)) {
-    const chunk = parseSseDataLine(line);
+    const chunk = parseSseDataLine(line, maxDataLineBytes);
     if (!chunk) continue;
+    chunkCount += 1;
 
     const deltaContent = collectDeltaContent(chunk);
     if (deltaContent) {
@@ -276,35 +271,35 @@ const readChatCompletionStream = async (
       usage = chunk.usage;
     }
 
-    chunks.push({
-      id: chunk.id,
-      created: chunk.created,
-      model: chunk.model,
-      content: deltaContent || undefined,
-      finishReason: chunk.choices?.find((choice) => choice.finish_reason)
-        ?.finish_reason,
-      metadata: chunk.metadata,
-      hasUsage: Boolean(chunk.usage)
-    });
+    finishReason =
+      chunk.choices?.find((choice) => choice.finish_reason)?.finish_reason ??
+      finishReason;
   }
 
   return {
     content,
-    chunks,
+    contentLength: content.length,
+    chunkCount,
+    finishReason,
     usage
   };
 };
 
 /** 解析单行 SSE data，跳过空行和 [DONE] */
-const parseSseDataLine = (line: string): IChatCompletionStreamChunk | null => {
+const parseSseDataLine = (
+  line: string,
+  maxDataLineBytes: number
+): IChatCompletionStreamChunk | null => {
   const trimmed = line.trim();
   if (!trimmed.startsWith("data:")) return null;
 
   const data = trimmed.slice("data:".length).trim();
   if (!data || data === "[DONE]") return null;
 
-  // TODO: JSON.parse 仍运行在主线程；如果后续接入更大的 SSE chunk，需要增加单行大小保护，
-  // 避免异常大包在单个 tick 内长时间占用事件循环。
+  if (textEncoder.encode(data).byteLength > maxDataLineBytes) {
+    throw new Error("图片生成失败：流式响应过大");
+  }
+
   return JSON.parse(data) as IChatCompletionStreamChunk;
 };
 
@@ -322,3 +317,18 @@ const collectDeltaContent = (chunk: IChatCompletionStreamChunk) => {
 const cleanupImageUrl = (url: string) => {
   return url.replace(/[,.!?，。！？]+$/u, "");
 };
+
+/** 限制尚未切分出换行的 SSE 缓冲区，避免异常长 data 行持续堆在内存里 */
+const assertSseBufferSize = (buffer: string, maxDataLineBytes: number) => {
+  if (
+    !buffer.includes("\n") &&
+    textEncoder.encode(buffer).byteLength > maxDataLineBytes
+  ) {
+    throw new Error("图片生成失败：流式响应过大");
+  }
+};
+
+const getPositiveIntegerEnv = (name: string, fallback: number) => {
+  const value = Number.parseInt(process.env[name] ?? "", 10);
+  return Number.isInteger(value) && value > 0 ? value : fallback;
+};