将服务添加到自定义路由装饰器 nestjs

Question

I have a Custom Route Decorator which is suppose to use a method from a Service but the service returns undefined. TypeError: Cannot read property 'findCustomer' of undefined ; Fairly new to nestjs

//Custom Route Decorator - CustomerDecorator

export async function getCustomerFromExeContext(
  context: ExecutionContext,
): Promise<Customer> {
  let organizationService: OrganizationService;
  const req = context.switchToHttp().getRequest<Request>();

  if (!req.params.orgId)
    throw new HttpException('OrgId not found', HttpStatus.UNAUTHORIZED);

  const customer = await organizationService.findCustomer(
    parseInt(req.params.orgId),
  );
  if (!customer) {
    throw new HttpException('Customer not found', HttpStatus.NOT_FOUND);
  }
  return customer;
}

export const GetCustomer = createParamDecorator(
  (_, context: ExecutionContext) => getCustomerFromExeContext(context),
);

This is the Route within the controller that utilize the Decorator

//Controller

@Get(':orgId')
  get(@GetCustomer() customer: Customer) {
    return this.organizationService.get(customer.customerId);
  }

Is there a way I can call and use the service within the decorator function without returning undefined ?

Answer 1

The error tells clearly what exactly happening

TypeError: Cannot read property 'findCustomer' of undefined

The error means organizationService is undefined and you are calling findCustomer on undefined.

Here

let organizationService: OrganizationService;

you create an undefined variable. you need to initialize it first.

If you have any dependency inside OrganizationService then you need to inject that class object. if not just new OrganizationService() will work