在 Nest.js 中，如何在装饰器中获取服务实例？

Question

在 CustomDecorator 中，如何访问 Nest.js 中定义的服务实例？

 export const CustomDecorator = (): MethodDecorator => {
  return (
    target: Object,
    propertyKey: string | symbol,
    descriptor: PropertyDescriptor
    ) => {

    // Here, is possibile to access a Nest.js service (i.e. TestService) instance?

    return descriptor;
  }
};

原文由 gremo 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 1

派对迟到了，但由于我遇到了类似的问题（ 在装饰器中使用全局嵌套模块）并且偶然发现了这个问题。

 import { Inject } from '@nestjs/common';
export function yourDecorator() {
  const injectYourService = Inject(YourServiceClass);

  return (target: any, propertyKey: string, propertyDescriptor: PropertyDescriptor) => {
    // this is equivalent to have a constructor like constructor(yourservice: YourServiceClass)
    // note that this will injected to the instance, while your decorator runs for the class constructor
    injectYourService(target, 'yourservice');

    // do something in you decorator

    // we use a ref here so we can type it
    const yourservice: YourServiceClass = this.yourservice;
    yourservice.someMethod(someParam);
  };
}

原文由 florian norbert bepunkt 发布，翻译遵循 CC BY-SA 4.0 许可协议