num/cloudfunctions/getQRCode/index.js

const cloud = require('wx-server-sdk');
cloud.init({ env: cloud.DYNAMIC_CURRENT_ENV });

// 生成小程序码（能量师专属推广码）
exports.main = async (event) => {
  const { referralCode } = event;
  const { OPENID } = cloud.getWXContext();

  if (!referralCode) {
    return { code: 400, error: '缺少推广码' };
  }

  try {
    const result = await cloud.openapi.wxacode.get({
      path: `pages/index/index?ref=${referralCode}`,
      width: 280,
      isHyaline: false,
      autoColor: true,
    });

    // 将 Buffer 上传到云存储
    const uploadRes = await cloud.uploadFile({
      cloudPath: `qrcode/${OPENID}_${referralCode}_${Date.now()}.jpg`,
      fileContent: result.buffer,
    });

    return {
      code: 0,
      fileID: uploadRes.fileID,
    };
  } catch (err) {
    return { code: 500, error: err.message };
  }
};