support inm

console-api/src/update/update.controller.ts

-import { Body, Controller, Get, Header, Ip, Param, ParseArrayPipe, Post, Query, Render, Res, ValidationPipe } from '@nestjs/common';
+import { Body, Controller, Get, Ip, Param, ParseArrayPipe, Post, Query, Render, Req, Res, ValidationPipe } from '@nestjs/common';
 import { UpdateService } from './update.service';
 import { ApiBody, ApiCreatedResponse, ApiOkResponse, ApiOperation, ApiParam, ApiTags } from '@nestjs/swagger';
 import { DepotDto } from '../dto/Depot.dto';
-import { Response } from 'express';
+import { Request, Response } from 'express';
 import { createHash } from 'crypto';
 
+function md5HexOfString(s: string) {
+  return createHash('md5').update(s).digest('hex');
+}
+
+/**
+ * 以“稳定字节串”为准计算 ETag，并发送响应。
+ * - 不捕获异常，让 Nest 接管错误处理
+ * - 若 If-None-Match 命中，返回 304
+ * - 若未显式设置 Cache-Control，则使用传入的默认值
+ */
+async function stableSend(
+  req: Request,
+  res: Response,
+  body: any | Promise<any>,
+  defaultCache = 'public, max-age=31536000, immutable',
+  contentType = 'application/json; charset=utf-8'
+): Promise<void> {
+  const bodyResolved = await body;
+  const bodyString = typeof bodyResolved === 'string' ? bodyResolved : JSON.stringify(bodyResolved);
+  const hash = md5HexOfString(bodyString);
+  const quoted = `"${hash}"`;
+
+  // 协商缓存：If-None-Match 命中则 304
+  const inm = req.headers['if-none-match'];
+  if (typeof inm === 'string' && inm === quoted) {
+    res.setHeader('ETag', quoted);
+    if (res.getHeader('Cache-Control') === undefined) {
+      res.setHeader('Cache-Control', defaultCache);
+    }
+    res.status(304).end();
+    return;
+  }
+
+  // 设置头
+  res.setHeader('ETag', quoted);
+  if (res.getHeader('Cache-Control') === undefined) {
+    res.setHeader('Cache-Control', defaultCache);
+  }
+  if (!res.getHeader('Content-Type')) {
+    res.setHeader('Content-Type', contentType);
+  }
+
+  // 发送“刚刚参与了 MD5 计算”的同一份字节串
+  res.end(bodyString);
+}
+
 @Controller('update')
 @ApiTags('update')
 export class UpdateController {
   constructor(private readonly updateService: UpdateService) {}
-  @Get('apps.json')
-  @ApiOperation({ summary: '获取 apps.json', description: '懒得解释这是啥了……' })
-  async getAppsJson(@Res({ passthrough: true }) res: Response) {
-    const result = await this.updateService.getAppsJson();
-    this.addETag(res, JSON.stringify(result));
-    res.setHeader('Cache-Control', 'public, max-age=600, stale-while-revalidate=600, stale-if-error=604800');
-    return result;
-  }
 
-  private addETag(res: Response, data: any) {
-    const hash = createHash('md5').update(JSON.stringify(data)).digest('hex');
+  private async stableReturn<T>(res: Response, prom: Promise<T> | T, cache = 'public, max-age=31536000, immutable') {
+    const result = await prom;
+    const stringified = JSON.stringify(result);
+    const hash = createHash('md5').update(stringified).digest('hex');
     res.setHeader('ETag', `"${hash}"`);
+    if (res.getHeader('Cache-Control') === undefined) res.setHeader('Cache-Control', cache);
+    res.end(stringified);
+    // return result;
   }
 
-  private async cacheResult<T>(res: Response, prom: Promise<T>) {
-    const result = await prom;
-    this.addETag(res, result);
-    if (res.getHeader('Cache-Control') === undefined) res.setHeader('Cache-Control', 'public, max-age=31536000, immutable');
-    return result;
+  @Get('apps.json')
+  @ApiOperation({ summary: '获取 apps.json', description: '懒得解释这是啥了……' })
+  async getAppsJson(@Req() req: Request, @Res({ passthrough: true }) res: Response) {
+    await stableSend(req, res, this.updateService.getAppsJson(), 'public, max-age=600, stale-while-revalidate=600, stale-if-error=604800');
+    return;
   }
 
   @Get('checksums/:id/:version')
-  @Render('checksums')
   @ApiOperation({ summary: '获取 app 校验和', description: '是 shasum 的格式' })
   @ApiParam({ name: 'id', description: 'APP 的 id' })
   @ApiParam({ name: 'version', description: 'APP 的版本号' })
   @ApiOkResponse({ type: String })
-  // @Header('Cache-Control', 'public, max-age=31536000, immutable')
+  // @Header('Cache-Control', 'public, max-age=31536000, immutable') // 可留给 stableSend 兜底
   async getChecksum(
+    @Req() req: Request,
+    @Res({ passthrough: true }) res: Response,
     @Param('id') id: string,
     @Query(new ValidationPipe({ transform: true })) depot: DepotDto,
     @Param('version') version: string,
-    @Res({ passthrough: true }) res: Response
   ) {
-    return this.cacheResult(res, this.updateService.getChecksum(id, depot, version));
+    await stableSend(req, res, this.updateService.getChecksum(id, depot, version));
+    return;
   }
 
   @Get('metalinks/:id/:version')