typescript - 如何为 mongoose 'Query' 添加类型

Question

我正在尝试将缓存层添加到我的 typescript 项目中。当我搜索时，我在媒体 How to add a Redis cache layer to Mongoose in Node.js 上找到了一篇文章

他通过在mongoose.Query.prototype中添加一个函数来实现缓存

mongoose.Query.prototype.cache = function(options = { time: 60 }) {
  this.useCache = true;
  this.time = options.time;
  this.hashKey = JSON.stringify(options.key || this.mongooseCollection.name);

  return this;
};

然后在 mongoose.Query.prototype.exec 中检查查询是否启用了缓存

mongoose.Query.prototype.exec = async function() {
    if (!this.useCache) {
        return await exec.apply(this, arguments);
    }

    const key = JSON.stringify({
        ...this.getFilter(),
    });
    console.log(this.getFilter());
    console.log(this.hashKey);

    const cacheValue = await client.hget(this.hashKey, key);

    if (cacheValue) {
        const doc = JSON.parse(cacheValue);

        console.log("Response from Redis");
        return Array.isArray(doc)
            ? doc.map((d) => new this.model(d))
            : new this.model(doc);
    }

    const result = await exec.apply(this, arguments);
    return result;
};

现在通过在 mongoose 查询中调用 cache() 函数来启用缓存

 books = await Book.find({ author: req.query.author }).cache();

一切正常，然后我尝试将它转换为 typescript ，但我不知道如何为其添加类型定义

typescript 版本总是报错

Property 'cache' does not exist on type 'Query<any>',
Property 'useCache' does not exist on type 'Query<any>',
Property 'hashKey' does not exist on type 'Query<any>',

有什么方法可以将这些类型添加到“查询”中吗？请帮助我

Answer 1

我最终通过执行以下操作使它正常工作。另见 https://stackoverflow.com/a/70656849/1435970

创建文件 /src/@types/mongoose.d.ts 并向其中添加以下内容:

type CacheOptions = {key?: string; time?: number}

declare module 'mongoose' {
  interface DocumentQuery<T, DocType extends import('mongoose').Document, QueryHelpers = {}> {
    mongooseCollection: {
      name: any
    }
    cache(options?: CacheOptions): any
    useCache: boolean
    hashKey: string
  }

  interface Query<ResultType, DocType, THelpers = {}, RawDocType = DocType> extends DocumentQuery<any, any> {}
}