我正在尝试在typescript中实现一个惰性数据库连接集合。我正在创建一个名为DatabaseCollection的类，我的想法是使用代理来延迟加载连接（我使用knex作为连接器），这个类在节点上下文方面工作得很好，但Typescript说“属性不存在”，我不知道如何告诉Typescript动态属性类。
我使用了一个转换为Record<string, Knex>的变通方法，但我想正确地实现它，提前感谢。
下面是代码：

const debug = true
process.env['DB_TEST_URL'] = 'mysql://root@localhost/test';

class NotImportantConnector {
    public url: string;

    constructor(url: string) {
        this.url = url;
    }
}

function dbFromURL(url: string): NotImportantConnector {
    return new NotImportantConnector(url);
}

class DatabasesCollection<T> {
    protected databases: Record<string, T> = {};

    constructor() {
        return new Proxy(this, this) as any;
    }

    get (target: DatabasesCollection<T>, name: string): T {
        if (name in target.databases) {
            return target.databases[name];
        }

        const envName = `DB_${name.replace(/[A-Z]/g, l => `_${l}`).toUpperCase()}_URL`;

        if (!process.env[envName]) {
            throw new Error(`Call to database ${name} needs ${envName} environment variable to run`);
        }

        target.databases[name] = dbFromURL(process.env[envName] as string) as T;
        return target.databases[name];
    }
}

// Not working with error Property 'test' does not exist on type 'DatabasesCollection<NotImportantConnector>'.
// const db = new DatabasesCollection<NotImportantConnector>();

// Workaround, using as 
const db = new DatabasesCollection<NotImportantConnector>() as unknown as Record<string, NotImportantConnector>;

console.log(db.test);