Nested controllers in Nestjs

It's common to have nested routes in REST APIs. Basically, I mean having routes like this:

/post/:id <- PARENT ROUTE
/post/:id/comments <- NESTED ROUTE
/post/:id/comments/:id <- NESTED ROUTE

And two controllers: the Post controller (first route) and the PostComments controller (nested routes)

By looking at the nestjs documentation is not easy to know how to do it.

But here's an example:

@Controller("posts/:postId")
export class PostCommentsController {

  @Get("comments")
  async listComments(@Param() params): Promise<CommentResponse[]> {
    const { postId } = params;
    ...
  }
  @Get("comments/:commentId")
  async getComment(@Param() params): Promise<CommentResponse> {
     const { postId, commentId } = params;
  }
}

We need to specify the parent route in the @Controller annotation.

In fact, PostCommentsController is not strictly nested (when you change the parent controller url, the child controller urls are not updated). But it works!

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