Add 卓米会 mini program and admin server.

Initial commit of the WeChat mini program, Express backend, and admin console.

Co-authored-by: Cursor <cursoragent@cursor.com>

server/lib/upload.js

@@ -0,0 +1,52 @@
+const crypto = require('crypto')
+const fs = require('fs')
+const path = require('path')
+const multer = require('multer')
+const { ok, fail } = require('./http')
+
+const uploadDir = process.env.UPLOAD_DIR
+  ? path.resolve(process.env.UPLOAD_DIR)
+  : path.join(__dirname, '..', 'public', 'uploads')
+
+const IMAGE_RE = /^image\/(png|jpe?g|webp)$/i
+const VIDEO_RE = /^video\/(mp4|quicktime|webm)$/i
+
+const storage = multer.diskStorage({
+  destination(req, file, cb) {
+    fs.mkdirSync(uploadDir, { recursive: true })
+    cb(null, uploadDir)
+  },
+  filename(req, file, cb) {
+    const ext = path.extname(file.originalname || '').toLowerCase() || '.bin'
+    cb(null, `${Date.now().toString(36)}${crypto.randomBytes(3).toString('hex')}${ext}`)
+  }
+})
+
+function uploader(options) {
+  const imagesOnly = !!(options && options.imagesOnly)
+  const middleware = multer({
+    storage,
+    limits: { fileSize: imagesOnly ? 5 * 1024 * 1024 : 80 * 1024 * 1024 },
+    fileFilter(req, file, cb) {
+      const mime = file.mimetype || ''
+      const allowed = IMAGE_RE.test(mime) || (!imagesOnly && VIDEO_RE.test(mime))
+      cb(null, allowed)
+    }
+  }).single('file')
+
+  return (req, res) => {
+    middleware(req, res, (error) => {
+      if (error) {
+        const tooLarge = error.code === 'LIMIT_FILE_SIZE'
+        return fail(res, 400, tooLarge ? (imagesOnly ? '图片需小于 5MB' : '文件需小于 80MB') : '上传失败')
+      }
+      if (!req.file) {
+        return fail(res, 400, imagesOnly ? '仅支持 png/jpg/webp 图片' : '仅支持 png/jpg/webp 图片或 mp4/mov/webm 视频')
+      }
+      const type = VIDEO_RE.test(req.file.mimetype) ? 'video' : 'image'
+      ok(res, { url: `/static/uploads/${req.file.filename}`, type })
+    })
+  }
+}
+
+module.exports = { uploader, uploadDir }