Adding Nest.js' data passing pattern to decorators

[sannajammeh]

Currently this functionality taken from Nest.js docs isn't possible as far as I know.

export function Auth(...roles: Role[]) {
  return applyDecorators(
    SetMetadata('roles', roles),
    UseGuards(AuthGuard, RolesGuard),
    ApiBearerAuth(),
    ApiUnauthorizedResponse({ description: 'Unauthorized' }),
  );
}

I am unable unsure about how one would make this possible is next-api-decorators.

export const Auth = createMiddlewareDecorator(
  async (req: NextApiRequest, _: NextApiResponse, next: NextFunction) => {
    // Auth logic ...
    next();
  }
);

class DashboardHandler {
  @Post()
  @Auth(RolesEnum.Admin) // Not possible afaik
  public async someEndpointWithAdminRole(@Body(ValidationPipe) courseDTO: CreateCourseDTO) {
      //...
  }
}

Perhaps adding a data argument behind the NextFunction is the way to go.

export const Auth = createMiddlewareDecorator(
  async (req: NextApiRequest, _: NextApiResponse, next: NextFunction, data: string) => {
    // Auth logic ...
    next();
  }
);

class DashboardHandler {
  @Post()
  @Auth(RolesEnum.Admin) // Should work 
  public async someEndpointWithAdminRole(@Body(ValidationPipe) courseDTO: CreateCourseDTO) {
      //...
  }
}

Or having a custom applyDecorators function like Nest.js would also make this process delightful.

[ggurkal]

You can have it as:

export const Auth = (role: string) => createMiddlewareDecorator(
  async (req: NextApiRequest, _: NextApiResponse, next: NextFunction, data: string) => {
    // Auth logic ...
    // Make use of the `role`
    next();
  }
);

Does it serve your needs?

[sannajammeh]

That creates this type: (role: string) => () => (target: object, propertyKey?: string | symbol | undefined) => void. Is this a valid decorator call? For example

export const Auth = (role: string) => createMiddlewareDecorator(
  async (req: NextApiRequest, _: NextApiResponse, next: NextFunction, data: string) => {
    // Auth logic ...
    // Make use of the `role`
    next();
  }
);

class Test {
   @Auth("admin") // () => (target: object, propertyKey?: string | symbol | undefined) => void
   test(){
   
   }
}

Following the intended usage:

export const Auth =  createMiddlewareDecorator(
  async (req: NextApiRequest, _: NextApiResponse, next: NextFunction, data: string) => {
    // Auth logic ...
    next();
  }
);

class Test {
   @Auth() //  (target: object, propertyKey?: string | symbol | undefined) => void
   test(){
   
   }
}

[ggurkal]

Sorry, missed one thing. This should do it:

export const Auth = (role: string) => createMiddlewareDecorator(
  async (req: NextApiRequest, _: NextApiResponse, next: NextFunction) => {
    // Auth logic ...
    // Make use of the `role`
    next();
  }
)();