Rails 7.1: implementing ActiveModel Serializers and JSON responses with dynamic attributes
I'm dealing with I'm maintaining legacy code that I'm running into a question with ActiveModel Serializers in my Rails 7.1 application. I have a model `User` and I want to conditionally include an attribute `:admin` in my JSON response based on the user's role. However, when I attempt to serialize the user object, the `:admin` attribute is not appearing in the output even when it should. Here's a simplified version of my `UserSerializer`: ```ruby class UserSerializer < ActiveModel::Serializer attributes :id, :name, :email def admin object.role == 'admin' ? true : nil end end ``` In my controller, I am trying to render the user: ```ruby class UsersController < ApplicationController def show user = User.find(params[:id]) render json: user, serializer: UserSerializer end end ``` When I make a request to `/users/1`, I expect the response to include `"admin": true` if the user is an admin, but it’s not appearing in the JSON response at all. I’ve checked the `object.role` and it returns correctly, but the attribute `:admin` is just not included in the output. I’ve tried explicitly specifying the `:admin` attribute in the `attributes` method, but that throws an behavior about undefined method. I also looked into using the `key` option, but that didn’t help either. Do I need to change something in the way I'm defining the `admin` method? Is there a specific reason why conditional attributes might not show up in the JSON response with ActiveModel Serializers? Any insights would be really helpful! Here’s the response I’m getting: ```json { "id": 1, "name": "John Doe", "email": "john@example.com" } ``` For context: I'm using Ruby on Windows. How would you solve this? What's the best practice here? I'm developing on Ubuntu 22.04 with Ruby. Thanks for any help you can provide!