Rails: One-to-One relationship not working - ruby-on-rails

Question

I am working on a Rails project and I am using namespacing for the models and controllers. That is the child models (admin and student) are put in a directory called user and the controllers are put in a directory called users.
I also have admins_controller and students_controller that use the admin model and the student model respectively. These controllers are namespaced using users directory.
I then have a personal_info model that contains more details about the user, such as gender, age, date of birth. The personal_info table has a one-to-one relationship with the user model.
Here's my code;
Personal Info model:
class PersonalInfo < ApplicationRecord
belongs_to :user
end
User model:
class User < ApplicationRecord
has_secure_password
has_one :personal_info, class_name: 'PersonalInfo', dependent: :destroy
accepts_nested_attributes_for :personal_info, allow_destroy: true
end
Admin model:
class User::Admin < User
end
Admin Controller:
class Users::AdminsController < ApplicationController
before_action :set_admin, only: [:show, :edit, :update, :destroy]
# GET /admins
# GET /admins.json
def index
#admins = User::Admin.all
end
# GET /admins/1
# GET /admins/1.json
def show
end
# GET /admins/new
def new
#admin = User::Admin.new
#admin.build_personal_info
end
# GET /admins/1/edit
def edit
end
# POST /admins
# POST /admins.json
def create
#admin = User::Admin.new(admin_params)
#admin.build_personal_info
respond_to do |format|
if #admin.save
format.html { redirect_to users_admin_path(#admin), notice: 'Admin was successfully created.' }
format.json { render :show, status: :created, location: users_admin_path(#admin) }
else
format.html { render :new }
format.json { render json: #admin.errors, status: :unprocessable_entity }
end
end
end
# PATCH/PUT /admins/1
# PATCH/PUT /admins/1.json
def update
respond_to do |format|
if #admin.update(admin_params)
format.html { redirect_to users_admin_path(#admin), notice: 'Admin was successfully updated.' }
format.json { render :show, status: :ok, location: users_admin_path(#admin) }
else
format.html { render :edit }
format.json { render json: #admin.errors, status: :unprocessable_entity }
end
end
end
# DELETE /admins/1
# DELETE /admins/1.json
def destroy
#admin.destroy
respond_to do |format|
format.html { redirect_to users_admins_url, notice: 'Admin was successfully destroyed.' }
format.json { head :no_content }
end
end
private
# Use callbacks to share common setup or constraints between actions.
def set_admin
#admin = User::Admin.find(params[:id])
end
# Only allow a list of trusted parameters through.
def admin_params
params.require(:user_admin).permit(
:email, :password, :role_id,
personal_info_attributes: [ :id, :first_name, :last_name, :phone,
:gender, :dob, :address, :city, :state,
:country ]
)
end
end
Routes:
Rails.application.routes.draw do
namespace :users do
resources :admins
resources :students
end
end
_form.html.erb:
<% if #admin.errors.any? %>
<div id="error_explanation">
<h2><%= pluralize(#admin.errors.count, "error") %> prohibited this admin from being saved:</h2>
<ul>
<% #admin.errors.full_messages.each do |message| %>
<li><%= message %></li>
<% end %>
</ul>
</div>
<% end %>
<%= fields_for :personal_info do |form| %>
<div class="field">
<%= form.label :first_name %>
<%= form.text_field :first_name %>
</div>
<div class="field">
<%= form.label :last_name %>
<%= form.text_field :last_name %>
</div>
<% end %>
<div class="field">
<%= form.label :email %>
<%= form.text_field :email %>
</div>
<%= fields_for :personal_info do |form| %>
<div class="field">
<%= form.label :phone %>
<%= form.text_field :phone %>
</div>
<% end %>
<div class="field">
<%= form.label :password %>
<%= form.text_field :password %>
</div>
<div class="actions">
<%= form.submit %>
</div>
new.html.erb:
<h1>Editing Admin</h1>
<%= form_with(model: #admin, url: users_admins_path, local: true) do |form| %>
<%= render partial: 'form', admin: #admin, locals: { form: form } %>
<% end %>
<%= link_to 'Back', users_admins_path %>
However, when I try to create a new admin or update an already existing admin after adding inputs to the displayed form no Personal Info data is saved on the database. They are all nil.
PersonalInfo Load (0.3ms) SELECT "personal_infos".* FROM "personal_infos" WHERE "personal_infos"."user_id" = $1 LIMIT $2 [["user_id", 6], ["LIMIT", 1]]
=> #<PersonalInfo id: 2, first_name: nil, last_name: nil, phone: nil, gender: nil, dob: nil, address: nil, city: nil, state: nil, country: nil, user_id: 6, created_at: "2020-06-26 13:37:16", updated_at: "2020-06-26 13:37:16">
I have tried to get this resolved, but no luck yet. Any form of help will be highly appreciated.

Answer 1

you should call your fields_for from admin form as:
<%= form.fields_for :personal_info do |form| %>
otherwise it sends these params independent from admin, rather than nested as you'd like.
fwiw, for better reading, I would consider rename your inner personal_info form variable to not clash with admin form variable. But that's just a suggestion. :)