我试图通过重写exec方法并向mongoose查询原型添加一个cache方法来缓存我的一些查询。正在保存查询，但正在删除哈希
这是我的密码：
在cache.js中

const mongoose = require("mongoose");
const redis = require("redis");
const client = redis.createClient({ url: process.env.REDIS_URL });
const exec = mongoose.Query.prototype.exec;

const hget = client.hget;
client.hget = function (key, field) {
  return new Promise((resolve, reject) => {
    hget.apply(client, [
      key,
      field,
      (err, val) => {
        if (err) {
          return reject(err);
        }
        resolve(val);
      }
    ]);
  });
};

mongoose.Query.prototype.cache = function (key) {
  this.shouldCache = true;
  this.hashKey = key || "default";
  return this;
};

mongoose.Query.prototype.exec = async function () {
  if (!this.shouldCache) {
    return exec.apply(this, arguments);
  }
  const cacheKey = JSON.stringify({
    collection: this.mongooseCollection.name,
    ...this.getQuery()
  });
  const cachedVal = await client.hget(this.hashKey, cacheKey);
  if (cachedVal) {
    const queryRes = JSON.parse(cachedVal);
    return Array.isArray(queryRes)
      ? queryRes.map((doc) => {
          this.model(doc);
        })
      : this.model(queryRes);
  }
  const queryRes = await exec.apply(this, arguments);
  client.hset(this.hashKey, cacheKey, JSON.stringify(queryRes));
  return queryRes;
};

const clearHash = (hashKey) => {
  client.del(hashKey || "default");
};

const flushCache = () => {
  return new Promise((resolve) => {
    client.flushdb(() => {
      resolve();
    });
  });
};

const disconnectToRedis = () => {
  return new Promise((resolve) => {
    client.quit(() => {
      resolve();
    });
  });
};

module.exports = { clearHash, flushCache, disconnectToRedis };

在我的中间件中，在请求完成后清除哈希键：

const { clearHash } = require("../services/cache");

const clearCache = async (req, res, next) => {
  await next();
  console.log("clearing cache");
  clearHash();
  console.log("cleared cache");
};

module.exports = clearCache;

在我的路由文件中

const express = require("express");
const router = express.Router();
const clearCache = require("../middlewares/clearCache");
const AuthController = require("../controllers/Auth");

router.post("/register", clearCache, AuthController.register);
router.post("/login", AuthController.login);
router.get("/user", AuthController.getUser);

module.exports = router;

我使用了一个debugged来查看clearhash函数是否在处理请求之后被调用，它是，但它没有清除散列键。但是，如果我尝试从另一个文件调用该函数并尝试只运行该文件，则会清除哈希键。
我不知道怎么了。可能是某种导入错误。谢谢你的帮助。